Claims:WE CLAIM
1. A process for preparing catalyst composites for reducing olefin content from hydrocarbon streams, said process comprising:
a) mixing a source of alumina, a structure directing agent, an alkaline aqueous solution of an inorganic source of silica, a solution of an organic source of silica and water to obtain a homogeneous mixture;
b) hydrothermally treating said homogeneous mixture by heating at a temperature in the range of 150 °C to 180 °C to obtain a solid mass;
c) adjusting the pH of said solid mass to 7 by washing said solid mass with water, followed by drying at a temperature in the range of 100 °C to 140 °C to obtain a dried solid mass;
d) calcining said dried solid mass at a temperature in the range of 500° C to 600° C to obtain a zeolitic mass;
e) mixing said zeolitic mass with a compositing agent and an extrusion aid followed by pulverizing to obtain a powder;
f) adding a peptizing agent to said powder to obtain a semi-solid mass;
g) extruding said semi-solid mass to obtain formed bodies; and
h) drying said formed bodies at a temperature in the range 80 °C to 120 °C and calcining said dried formed bodies at a temperature in the range of 500 °C to 600 °C to obtain said catalyst composite.

2. The process as claimed in claim 1, wherein said homogeneous mixture obtained in step (a) is prepared by the following steps:
i) mixing said solution of said organic source of silica, said source of alumina, said structure directing agent and water to obtain a mixture;
ii) adding said alkaline aqueous solution of said inorganic source of silica into said mixture under stirring to obtain a gel;
iii) adjusting the pH of said gel in the range of 9 to 13 to obtain a pH adjusted gel; and
iv) digesting said pH adjusted gel by stirring said pH adjusted gel at a temperature in the range of 105 °C to 115 °C to obtain said homogeneous mixture.

3. The process as claimed in claim 1, wherein said homogeneous mixture obtained in step (a) is prepared by the following steps:
i) mixing said alkaline aqueous solution of said inorganic source of silica, said source of alumina, said structure directing agent and water to obtain a gel;
ii) adjusting the pH of said gel in the range of 9 to 13 to obtain a pH adjusted gel;
iii) digesting said pH adjusted gel by stirring said pH adjusted gel at a temperature in the range of 105 °C to 115 °C to obtain a digested gel; and
iv) adding said organic source of silica to said digested gel under stirring to obtain said homogeneous mixture.

4. The process as claimed in claim 1, wherein said solution of said organic source of silica in step (a) comprises at least one organic source of silica and at least one alcohol selected from the group consisting of methanol, ethanol, propanol, and isopropanol.

5. The process as claimed in any one of claims 1 to 4, wherein said organic source of silica is at least one organic silane surfactant selected from the group consisting of mPEG20K-Silane, mPEG5K-Silane, octyltriethoxysilane, trichloro(octadecyl)silane, dimethyloctadecyl[3-(trimethoxysilyl) propyl]ammonium chloride, tetradecyldimethyl(3-trimethoxysilylpropyl)ammonium chloride, phenylaminopropyl-trimethoxysilane, [3-(trimethoxysilyl) propyl] hexadecyl dimethylammonium chloride, [3-(trimethoxysilyl)propyl] dodecyldimethylammonium chloride, silane-functionalized polyethyleneimine polymer, (3-chloropropyl)trimethoxysilane and dimethyloctadecyl[3-(trimethoxysilyl)propyl] ammonium chloride.

6. The process as claimed in claim 1, wherein said source of alumina in step (a) is hydrated aluminum sulfate.

7. The process as claimed in claim 1, wherein said structure directing agent in step (a) is at least one selected from the group consisting of butyl triethylammoniumbromide (BTAB) and tetra-propyl ammonium bromide (TPAB).

8. The process as claimed in claim 1, wherein said alkaline aqueous solution of the inorganic source of silica in step (a) comprises said inorganic source of silica, water and at least one base selected from the group consisting of sodium hydroxide, potassium hydroxide, and calcium hydroxide.

9. The process as claimed in any one of claims 1, 2, 3 and 8, wherein said inorganic source of silica is at least one selected from the group consisting of sodium silicate, silica gel, precipitated silica, colloidal silica, and fumed silica.

10. The process as claimed in claim 1, wherein said zeolitic mass obtained in step (d) is at least one selected from the group consisting of ZSM-5, ZSM-11, isomorphous substituted hetero-atom incorporated ZSM-5, and isomorphous substituted hetero-atom incorporated ZSM-11.

11. The process as claimed in claim 1, wherein said compositing agent in step (e) is selected from the group consisting of oxides of aluminum, oxides of phosphorous, and aluminium phosphate, and aluminium phosphate hydrogel.

12. The process as claimed in claim 1, wherein said extrusion aid in step (e) is hydroxyl methyl propyl cellulose.

13. The process as claimed in claim 1, wherein said peptizing agent in step (f) is 2.5 to 4.5 wt% aqueous acetic acid.

14. The process as claimed in claim 1, wherein the mole ratio of said organic source of silica to said inorganic source of silica is in the range of 100:1 to 100:5.

15. The process as claimed in claim 1, wherein the mole ratio of silica to alumina in said zeolitic mass of step (c) is in the range of 10:1 to 200:1.

16. The process as claimed in claim 1, wherein the weight ratio of said zeolite to said compositing agent in step (e) is in the range of 1:10 to 10:1.

17. The process as claimed in claim 1, wherein said formed bodies in step (g) have at least one shape selected from the group consisting of spherical, cylindrical, tri-lobe, tetra-lobe, star, ring, tablets, pellets, and honey comb.

18. The process as claimed in claim 1, wherein said formed bodies are tetra-lobe.

19. A catalyst composite obtained using the process as claimed in claim 1, wherein said catalyst composite comprises said zeolitic mass, and said compositing agent, wherein said zeolitic mass is at least one selected from the group consisting of ZSM-5, ZSM-11, isomorphous substituted hetero-atom incorporated ZSM-5, and isomorphous substituted hetero-atom incorporated ZSM-11, wherein the mole ratio of silica to alumina in said zeolitic mass is in the range of 10:1 to 200:1, wherein said zeolitic mass is characterized in that the surface area is in the range of 300 to 600 m2/g, total pore volume is in the range of 0.35 to 0.45 mL/g, meso pore volume is in the range of 0.10 to 0.60 mL/g and average pore width is in the range of 0.10 to 0.60 Å.
, Description:FIELD
The present disclosure relates to catalyst composites for reducing olefin content of hydrocarbon streams.
DEFINITIONS
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicate otherwise.
Hydrothermal treatment: Hydrothermal treatment employs the combination of heat and water as a media to convert reactants having different characteristics into uniform product.
Structure-directing agent: Structure-directing agents are templates used to guide the formation of particular types of pores and channels during the synthesis of zeolites.
Compositing agent: Compositing agent is the material used for combining with a different material of separate source to form a single composite material.
BACKGROUND
Catalysts play an important role in the petroleum industry. Different catalysts are used for a variety of processes related to refineries and hydrocarbon conversions. To meet the demand and supply, the development of new catalysts and hydrocarbon conversion processes in the area of refining and petrochemicals is of commercial interest. Substitution of existing catalysts with newer environment friendly catalysts with higher efficacy, service life, enhanced process reliability and smoother operation is always desired.
Before converting a hydrocarbon stream to valuable products, the hydrocarbon stream needs to be free from olefin impurities. If the olefin impurities in the hydrocarbon stream are not reduced, then these cause detrimental effect in downstream processing, viz. (i) these olefin acts as poison for the specialty molecular sieve employed for para-xylene recovery by adsorptive process, (ii) causes gum formation and (iii) imparts colour in the downstream products. Conventionally, the olefin impurities are removed in up-stream adsorption units, where clay is used as the adsorbent. However, clay has a short life span. Further, the clay cannot be regenerated and therefore, it results in frequent change-over of clay, which in turn results in generation of a huge volume of solid waste.
Thus, there is felt a need to develop an alternative catalyst composite for reducing olefin content of a hydrocarbon stream.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows.
It is an object of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative.
An object of the present disclosure is to provide a catalyst composite for reducing olefins from a hydrocarbon stream.
Another object of the present disclosure is to provide a process for preparing a catalyst composite for reducing olefins from a hydrocarbon stream.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
In accordance with one aspect of the present disclosure, there is provided a process for preparing catalyst composites for reducing olefin content of hydrocarbon streams.
In one embodiment, the process for preparing catalyst composites comprises mixing a source of alumina, a structure directing agent, an alkaline aqueous solution of an inorganic source of silica, a solution of an organic source of silica and water to obtain a homogeneous mixture.
The homogeneous mixture is prepared by mixing a solution of an organic source of silica, a source of alumina and a structure directing agent with water to obtain a mixture. An alkaline aqueous solution of the inorganic source of silica is added into the mixture under stirring to obtain a gel. The pH of the so obtained gel is adjusted in the range of 9 to 13 by adding an acidic solution to obtain a pH adjusted gel. The pH adjusted gel is digested by stirring at a temperature in the range of 105 to 115 °C for a time period in the range of 15 hours to 19 hours to obtain the homogeneous mixture.
In accordance with one embodiment, the homogeneous mixture is prepared by mixing the alkaline aqueous solution of the inorganic source of silica, the source of alumina, the structure directing agent and water to obtain a gel. The pH of the gel is adjusted in the range of 9 to 13 to obtain the pH adjusted gel. The pH adjusted gel is digested by stirring the pH adjusted gel at a temperature in the range of 105 °C to 115 °C to obtain a digested gel. The organic source of silica is added to the digested gel under stirring to obtain the homogeneous mixture.
In accordance with another embodiment, the organic source of silica is added to the pH adjusted gel under stirring to obtain the homogeneous mixture, thereby avoiding the step of digestion of the pH adjusted gel.
In accordance with an embodiment of the present disclosure, the solution of the organic source of silica is at least one organic source of silica and at least one alcohol selected from the group consisting of methanol, ethanol, propanol, and isopropanol.
The organic source of silica is at least one organic silane surfactant selected from the group consisting of mPEG20K-Silane, mPEG5K-Silane, octyltriethoxysilane, trichloro(octadecyl)silane, dimethyloctadecyl[3-(trimethoxysilyl) propyl]ammonium chloride, tetradecyldimethyl(3-trimethoxysilylpropyl)ammonium chloride, phenylaminopropyl-trimethoxysilane, [3-(trimethoxysilyl) propyl] hexadecyl dimethylammonium chloride, [3-(trimethoxysilyl)propyl] dodecyldimethylammonium chloride, silane-functionalized polyethyleneimine polymer, (3-chloropropyl)trimethoxysilane and dimethyloctadecyl[3-(trimethoxysilyl)propyl] ammonium chloride.
In accordance with an embodiment of the present disclosure, the inorganic source of silica is at least one selected from the group consisting of sodium silicate, silica gel, precipitated silica, colloidal silica, and fumed silica.
The homogeneous mixture is then hydrothermally treated by heating the homogeneous mixture, at a temperature, typically in the range of 150 to 180 °C for a time period typically in the range of 90 to 105 hours, followed by separation of the crystallized solid product by any known means such as decantation, filtration, centrifuging and the like, to obtain a solid mass. The solid mass is washed with water, till pH of the solid mass is 7, followed by drying at a temperature in the range of 100°C to 150 °C to obtain a dried solid mass. The dried solid mass is calcined at a temperature in the range of 500 to 600 °C to obtain a zeolitic mass.
The zeolitic mass was repeatedly ion-exchanged and was converted to active acidic form by any known means.
The so obtained zeolitic mass is mixed with a compositing agent and an extrusion aid followed by pulverization to obtain a powder. A peptizing agent is added to the powder to obtain a semi-solid mass, which is then extruded through an extruder to obtain formed bodies. The formed bodies are dried and calcined to obtain the catalyst composite.
The zeolitic mass formed using the process of the present disclosure is at least one selected from the group consisting of ZSM-5, ZSM-11, isomorphous substituted hetero-atom incorporated ZSM-5, and isomorphous substituted hetero-atom incorporated ZSM-11.
In accordance with an embodiment of the present disclosure, the compositing agent is at least one selected from the group consisting of oxides of aluminum, oxides of silicon, oxides of phosphorous, aluminum phosphates, and aluminum phosphate hydrogel.
In accordance with an embodiment of the present disclosure, the alkaline aqueous solution of sodium silicate comprises sodium silicate, water and at least one base selected from the group consisting of sodium hydroxide, potassium hydroxide and calcium hydroxide.
In accordance with an embodiment of the present disclosure, the peptizing agent is 2.5 to 4.5 wt% aqueous acetic acid and the extrusion aid is hydroxypropyl methyl cellulose.
In accordance with an embodiment of the present disclosure, the mole ratio of the organic source of silica to the inorganic source of silica is in the range of 100:1 to 100:5. The mole ratio of silica to alumina in the zeolitic mass is in the range of 10:1 to 200:1. The weight ratio of the zeolitic mass to the compositing agent is in the range of 1:10 to 10:1.
In accordance with an embodiment of the present disclosure, the shape of the formed bodies are of at least one shape selected from the group consisting of spherical, cylindrical, tri-lobe, tetra-lobe, star, ring, tablets, pellets, and honey comb.
In accordance with another aspect of the present disclosure, there is provided a catalyst composite. The catalyst composite comprises the zeolitic mass obtained by the process of the present disclosure, selected from the group consisting of ZSM-5, ZSM-11, isomorphous substituted hetero-atom incorporated ZSM-5, isomorphous substituted hetero-atom incorporated ZSM-11, and a compositing agent. The mole ratio of silica to alumina in the zeolitic mass is in the range of 10:1 to 200:1 and the zeolitic mass is characterized by the surface area is in the range of 300 to 600 m2/g, total pore volume is in the range of 0.10 to 0.60 mL/g, meso pore volume is in the range of 0.10 to 0.60 mL/g and average pore width is in the range of 0.10 to 0.60 Å.
DETAILED DESCRIPTION
Olefins are impurities in a hydrocarbon stream. Therefore, there is a need of reducing olefin content in the hydrocarbon stream effectively. The present disclosure envisages a catalyst composite for reducing olefin content of the hydrocarbon stream and a process of preparation thereof.
In accordance with one aspect of the present disclosure, there is provided a process for preparing catalyst composites for reducing olefins of hydrocarbon streams. The process is carried out in the steps detailed herein below.
In one embodiment, a source of alumina, a structure directing agent, an alkaline aqueous solution of an inorganic source of silica, a solution of an organic source of silica and water are mixed to obtain a homogeneous mixture.
The homogeneous mixture is prepared by mixing the solution of an organic source of silica, the source of alumina and the structure directing agent with water to obtain the mixture. The alkaline aqueous solution of the inorganic source of silica is added into the mixture under stirring to obtain the gel. The pH of the so obtained gel is adjusted in the range of 9 to 13 by adding an acidic solution to obtain the pH adjusted gel. The pH adjusted gel is digested by stirring the pH adjusted gel at a temperature in the range of 105 °C to 115 °C for a time period in the range of 15 hours to 19 hours to obtain the homogeneous mixture.
In another embodiment, the homogeneous mixture is prepared by mixing the alkaline aqueous solution of an inorganic source of silica, the source of alumina, the structure directing agent and water to obtain a gel. The pH of the so obtained gel is adjusted in the range of 9 to 13 by adding an acidic solution to obtain the pH adjusted gel. The pH adjusted gel is digested by stirring the pH adjusted gel at a temperature in the range of 105 °C to 115 °C for a time period in the range of 15 hours to 19 hours to obtain a digested gel. The organic source of silica is added to the digested gel under stirring to obtain the homogeneous mixture.
In accordance with still another embodiment, the organic source of silica is added to the pH adjusted gel under stirring to obtain the homogeneous mixture, thereby avoiding the step of digestion of the pH adjusted gel.
The solution of the organic source of silica comprises an organic source of silica and at least one alcohol selected from the group consisting of methanol, ethanol, propanol, and isopropanol.
The organic source of silica is an organic silane surfactant selected from the group consisting of mPEG20K-Silane, mPEG5K-Silane, octyltriethoxysilane, trichloro(octadecyl)silane, dimethyloctadecyl[3-(trimethoxysilyl) propyl]ammonium chloride, tetradecyldimethyl(3-trimethoxysilylpropyl)ammonium chloride, phenylaminopropyl-trimethoxysilane, [3-(trimethoxysilyl) propyl] hexadecyl dimethylammonium chloride, [3-(trimethoxysilyl)propyl] dodecyldimethylammonium chloride, silane-functionalized polyethyleneimine polymer, (3-chloropropyl)trimethoxysilane and dimethyloctadecyl[3-(trimethoxysilyl)propyl] ammonium chloride.
The source of alumina is hydrated aluminum sulfate.
The structure directing agent is at least one selected from the group consisting of butyl triethylammoniumbromide (BTAB) and tetra-propyl ammonium bromide (TPAB).
In accordance with an embodiment of the present disclosure, the alkaline solution of the inorganic source of silica comprises sodium silicate, water and at least one base selected from the group consisting of sodium hydroxide, potassium hydroxide and calcium hydroxide. The inorganic source of silica is at least one selected from the group consisting of sodium silicate, silica gel, precipitated silica, colloidal silica, and fumed silica.
The so obtained homogeneous mixture is then hydrothermally treated by heating the homogeneous mixture at a temperature in the range of 150 °C to 180 °C for a time period in the range of 90 to 105 hours to obtain a solid mass. The pH of the solid mass is adjusted to 7 by washing it with water, followed by drying at a temperature in the range of 100 °C to 140 °C to obtain a dried solid mass. The dried solid mass is calcined at a temperature in the range of 500 °C to 600 °C to obtain a zeolitic mass.
The zeolitic mass formed using the process of the present disclosure is at least one is selected from the group consisting of ZSM-5, ZSM-11, isomorphous substituted hetero-atom incorporated ZSM-5, and isomorphous substituted hetero-atom incorporated ZSM-11.
The hydrothermal treatment of the gel enables crystallization of the gel to obtain the zeolitic mass. The crystallization occurs around the structure directing agent. Therefore, the use of structure directing agent is helpful in preparing zeolitic mass having high surface area and high pore volume.
Next, the so obtained zeolitic mass is mixed with at least one compositing agent and an extrusion aid followed by pulverization to obtain a powder. A peptizing agent is added to the powder to obtain a semi-solid mass, which is then extruded through an extruder to obtain formed bodies. The formed bodies are dried and calcined to obtain the catalyst composite.
In accordance with an embodiment of the present disclosure, the compositing agent is at least one selected from the group consisting of oxides of aluminum, oxides of phosphorous, aluminum phosphates and aluminophosphate hydrogel.
In accordance with an embodiment of the present disclosure, the peptizing agent is 2.5 to 4.5 wt% aqueous acetic acid.
In accordance with an embodiment of the present disclosure, the extrusion aid is hydroxyl methyl propyl cellulose.
In accordance with an embodiment of the present disclosure, the mole ratio of the organic source of silica to the inorganic source of silica is in the range of 100:1 to 100:5.
In accordance with an embodiment of the present disclosure, the mole ratio of silica to alumina in zeolitic mass is in the range of 10:1 to 200:1.
In accordance with an embodiment of the present disclosure, the weight ratio of zeolitic mass to the compositing agent is in the range of 1:10 to 10:1.
In accordance with an embodiment of the present disclosure, the formed bodies are of at least one shape selected from the group consisting of spherical, cylindrical, tri-lobe, tetra-lobe, star, ring, tablets, pellets, honey comb.
In accordance with another aspect of the present disclosure, there is provided a catalyst composite. The catalyst composite comprises zeolitic mass obtained by the process of the present disclosure, selected from the group consisting of ZSM-5, ZSM-11, isomorphous substituted hetero-atom incorporated ZSM-5, and isomorphous substituted hetero-atom incorporated ZSM-11, and a compositing agent. The mole ratio of silica to alumina in the zeolitic mass is in the range of 10:1 to 200:1.
The surface area of the zeolitic mass prepared using the process of the present disclosure is in the range of 300 to 600 m2/g.
The total pore volume of zeolitic mass prepared using the process of the present disclosure is in the range of 0.10 to 0.60 mL/g, meso pore volume is in the range of 0.10 to 0.60 mL/g and average pore width is in the range of 0.10 to 0.60 Å.
The zeolitic mass of the present disclosure is prepared using the two different sources of silica, the organic source of silica and the inorganic source of silica. The organic source of silica is organic silane surfactant, which acts as a source of silica and useful in preparing the zeolitic mass having desired properties. Zeolitic mass prepared by the process of the present disclosure, prepared using two sources of silica, exhibit higher surface area, higher total pore volume, higher meso pore volume and higher average pore width as compared to the zeolitic mass prepared using the conventional processes.
Conventionally, as the silica to alumina ratio of a zeolite is increased, the surface area, pore volume, average pore width decreases. This happens due to increase in crystal size with increase in silica to alumina ratio of synthesized zeolite. On the contrary, when zeolite with high silica to alumina ratio is prepared using the process of the present disclosure, surface area, pore volume, pore width of the zeolite are high. The zeolitic mass prepared using the conventional method having silica to alumina ratio of 100 exhibit surface area of 385 m2/g, total pore volume of 0.21 mL/g, meso pore volume of 0.13 mL/g and average pore width of 22 Å, whereas, the zeolitic mass having silica to alumina ratio of 108 prepared in accordance with the present disclosure exhibit surface area of 432, total pore volume of 0.40 mL/g, meso pore volume of 0.33 mL/g and average pore width of 37 Å.
The improvement in the physical properties of zeolitic mass prepared using the process of the present disclosure is reflected by their improved catalytic activity. On using the catalyst composites of the present disclosure for reducing the olefin impurity from the hydrocarbon stream remarkable amount of olefin is reduced in the product stream. The percent reduction of olefin from the hydrocarbon stream expressed as % BI (Bromine Index) reduction, using catalyst composites of the conventional processes is in the range of 10.6 % to 20.1%. Whereas, the percent reduction of olefin from the hydrocarbon stream expressed as % BI reduction, using catalyst composites of the present disclosure is in the range of 32.6 % to 43.1%.
Thus, catalyst composites prepared using the process of the present disclosure exhibit better performance for reduction of olefins from the hydrocarbon stream.
The present disclosure is further described in the light of the following laboratory experiments, which are set forth for illustration purpose only, and not to be construed for limiting the scope of the disclosure. The following experiments can be scaled up to industrial/commercial scale, and the results obtained can be extrapolated to industrial scale.
EXPERIMENTS
Experiment 1 (Comparative): Synthesis of ZSM-5 (SAR 40) and compositing with Al2O3
To a reactor, were added a solution comprising 555.6 g of sodium silicate (27 wt% SiO2, 14 wt% NaOH) in 1000 g water, 98.18 g of butyl-triethylammoniumbromide (BTAB) in 1000 g water and 39.38 g of aluminum sulphate, Al2(SO4)3?16 H2O in 637 g water under stirring to obtain a mixture. 53.23 g of sulfuric acid (conc. H2SO4) was slowly added into the mixture under continuous stirring to form a gel. pH of the gel was adjusted to 10 by adding 15.5 g of aqueous H2SO4 (1:1 weight ratio) to obtain a pH adjusted gel. The pH adjusted gel was agitated at room temperature for 2 hours to obtain a homogeneous mixture having molar composition as 20.4 Na2O : 40 SiO2 : 1 Al2O3 : 6.6 TEBA : 11.6 H2SO4 : 2652 H2O. Next, the homogeneous mixture was transferred to a stainless steel autoclave and the homogeneous gel was digested for 17 hours at 110 ºC, under continuous stirring to obtain a homogeneous mixture. The homogeneous mixture was hydrothermally treated by heating at 165 ºC and under autogenous pressure for a period of 90 hours to obtain a solid mass. The solid mass was filtered and washed with water, followed by drying at 110 ºC, to obtain a dried solid. The dried solid mass was calcined at 540 ºC for 6 hours to obtain a zeolitic mass.

X-Ray diffraction (XRD) analysis of the zeolitic mass, before and after calcination showed a single phase of ZSM-5 zeolite. The BET surface area of zeolitic mass was 395 m2/g, and total pore volume of the calcined zeolitic mass was 0.23 ml/g.
The zeolitic mass prepared was Na-ZSM-5. The Na+ ions of Na-ZSM-5 were exchanged with NH4+ by treating in an aqueous solution of 1 M NH4NO3 at 80 °C for 3 hours. The NH4+ exchanged form of ZSM-5 was calcined in air at 540 °C for 6 hours to obtain H-ZSM-5.

Compositing ZSM-5 (SAR -40 (Silica to alumina ratio)) with Alumina: 32.9 g Condia alumina (having LOI 27 wt.%), 1.0 g HPMC (hydroxypropyl methyl cellulose) and 63.9 g zeolitic mass were mixed thoroughly in a mortar-pastel to obtain a powder. 64.9 g aqueous solution comprising 3.7% acetic acid was added to the powder to obtain a semi-solid mass. The semi-solid mass was extruded through an extruder to obtain extrudates. Extrusion was carried out using a 1.5 mm die. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours in air. The dried extrudates were calcined at 540 °C for 6 hours under air to obtain the catalyst composite. The catalyst composite contains 70% by weight of ZSM-5 zeolite.

Experiment 2 (Comparative): Synthesis of ZSM-5 (SAR-80) and compositing with Al2O3
A reactor was charged with a solution of 987.7 g of sodium silicate (SiO2 27 wt%, 14 wt% NaOH) in 1000 g water, 87.27 g of butyltriethylammoniumbromide (BTAB) in 800 g water and 35 g of aluminum sulphate (Al2(SO4)3?16 H2O,) in 253 g water under stirring to obtain a mixture. 47.3 g of sulfuric acid (conc. H2SO4) was added slowly to the mixture with continuous stirring to obtain a gel. The pH of the gel was adjusted to 10 by adding 14.4 g of aqueous H2SO4 (1:1) solution to obtain a pH adjusted gel. The pH adjusted gel was further stirred continuously at room temperature for 2 hours to achieve a homogeneous gel having molar composition as 40.8 Na2O : 80 SiO2 : 1 Al2O3 : 6.6 TEBA : 11.7 H2SO4 : 2652 H2O
The homogeneous gel was transferred to a stainless steel autoclave and was digested by heating at 110 °C for 17 hours under continuous stirring, to obtain a digested gel. Next, the digested gel was hydrothermally treated by heating at 165 °C under autogenous pressure for 90 hours to obtain a homogeneous mixture, which was filtered, washed with water to obtain a solid mass. The solid was dried at 110 ºC to obtain a dried solid mass, which was calcined in air at 540 °C for 6 hours to obtain zeolitic mass. XRD analysis of zeolitic mass, before and after calcination showed single phase of ZSM-5 zeolite. The zeolitic mass had BET surface area of 386 m2/g and total pore volume of 0.20 mL/g
The Na+ ions of Na-ZSM-5 were exchanged with NH4+ by treating in an aqueous solution of 1M NH4NO3 at 80°C for 3 hours. The NH4+ form of ZSM-5 was calcined in air at 540 ºC for 6 hours to degas NH3 and obtain H-ZSM-5.

Compositing of ZSM-5 SAR-80 with Alumina: 32.9 g Condia alumina (having LOI 27 wt.%), 1.0 g HPMC and 62.9 g zeolitic mass were mixed thoroughly in a mortar-pastel to obtain a powder. 41.7 g aqueous solution comprising 3.7% acetic acid was added to the powder and pugged thoroughly to obtain a semi-solid mass. The semi-solid was extruded through an extruder to obtain extrudates. Extrusion was carried out using a 1.5 mm die. The extrudates were dried at room temperature for 1 hour, followed by drying at 120 °C for 6 hours in air. The dried extrudates were calcined at 540 °C for 6 hours under air to obtain the catalyst composite. The catalyst composite contains 70% by weight of ZSM-5 zeolite.

Experiment 3 (Comparative): Synthesis of ZSM-5 (SAR 100) and compositing with Al2O3
A reactor was charged with a solution of 1234 g of sodium silicate (27 wt% SiO2, 14 wt% NaOH) in 800 g water, 87.3 g of butyltriethylammoniumbromide (BTAB) in 700 g water and 35 g of aluminum sulphate (Al2(SO4)3?16 H2O) in 407 g of water under stirring to obtain a mixture. 47.3 g of sulfuric acid (conc. H2SO4) was added to the mixture slowly under stirring to obtain a gel. The pH of the gel was adjusted to 10 by adding 14.2 g of aqueous H2SO4 (1:1) solution to the gel to obtain a pH adjusted gel. The pH adjusted gel was stirred continuously at room temperature for 2 hours to obtain a homogeneous hydrogel having molar composition as 51 Na2O: 100 SiO2: 1 Al2O3: 6.6 TEBA: 11.7 H2SO4: 2652 H2O.
The homogeneous gel was transferred to an autoclave and was digested by heating at 110 °C for 17 hours under continuous stirring to obtain a digested gel. The digested gel was hydrothermally treated at 165 °C and under autogenous pressure for a time period of 90 hours to obtain a solid mass. The solid mass was recovered by filtration and washed with water to obtain a washed solid. The washed solid was dried at 110 °C in air to obtain a dried solid mass, which was calcined in air at 540 ºC for 6 hours to obtain zeolitic mass. XRD analysis of zeolitic mass, before and after calcination showed single phase of ZSM-5 zeolite. The BET surface area of the zeolite was 385 m2/g and total pore volume was 0.21 ml/g.
The zeolitic mass prepared was Na-ZSM-5. The Na+ ions of Na-ZSM-5 were exchanged with NH4+ by treating in an aqueous solution of 1 M NH4NO3 at 80 °C for 3 hours. The NH4+ exchanged form of ZSM-5 was calcined in air at 540 °C for 6 hours to obtain H-ZSM-5.

Compositing of ZSM-5 SAR-100 with Alumina: 32.9 g Condia alumina (having LOI 27 wt.%), 1.0 g HPMC and 63.8 g zeolitic mass were mixed thoroughly in a mortar-pastel to obtain a powder. 44.9 g aqueous solution comprising 3.7% acetic acid was added to the powder and pugged thoroughly to obtain a semi-solid mass. The semi-solid mass was extruded through an extruder to obtain extrudates. Extrusion was done using a 1.5 mm die. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours in air. Dried sample was calcined at 540 °C for 6 hours under air. Zeolite content in the final composite (on loss free basis) was 70% by weight.

Experiment 4 (Present disclosure): Synthesis of ZSM-5 (SAR 108) and compositing with Al2O3
A reactor was charged with 22.2 g of a solution comprising 42.5 wt% dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (DMOD), 8 wt% (3-chloropropyl)trimethoxysilane, 49.5 wt% methanol and 114.7 g of water, 2.5 g of aluminum sulfate (Al2(SO4)3?16H2O), 5.9 g of butyltriethylammoniumbromide (BTAB) to obtain a mixture. 84.89 g of an alkaline aqueous solution comprising sodium silicate, (27 wt% SiO2, 13.7% NaOH) was slowly added to the mixture to obtain a gel. The pH of the gel was adjusted to 10 by adding 19 g of an aqueous sulfuric acid (9.5 g water and 9.5 g sulfuric acid) to obtain a pH adjusted gel.
The pH adjusted gel was transferred into an autoclave and digested at 110 ?C with stirring for 17 hours to obtain a homogeneous mixture. The homogeneous mixture was hydrothermally treated by heating the homogeneous mixture at 165 ?C for 96 hours to obtain a solid mass. The resulting solid mass was washed with water followed by drying at 120 ?C for 16 hours to obtain dried solid mass. The dried solid mass was calcined at 540 ?C for 16 hours to obtain zeolitic mass.
XRD of zeolitic mass revealed a single phase of ZSM-5 zeolite. The BET surface area of the zeolite was 432 m2/g and total pore volume was 0.40 ml/g. The zeolite prepared was Na-ZSM-5. The Na+ ions of Na-ZSM-5 were exchanged with NH4+ by treating in an aqueous solution of 1 M NH4NO3 at 80 °C for 3 hours. The NH4+ exchanged form of ZSM-5 was calcined in air at 540 °C for 6 hours to obtain H-ZSM-5.

Compositing of ZSM-5 SAR 108 with Al2O3: 30.8 g Condia alumina (having LOI 27 wt.%), 0.9 g HPMC and 72.9 g zeolitic mass were mixed thoroughly in a mortar-pastel to obtain a powder. 47.5 g aqueous solution comprising 3.7% acetic acid was added to the powder to obtain a semi-solid mass, which was extruded through an extruder to obtain extrudates. Extrusion was carried out using a 1.5 mm die. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours in air. The dried extrudates were calcined at 540 °C for 6 hours under air followed by calcination to obtain the catalyst composite. The zeolite content in the final catalyst composite (on loss free basis) was 70% by weight.

Experiment 5 (present disclosure): Synthesis of ZSM-5 (SAR 110) and shaping with Al2O3
A reactor was charged with 2.5 g aluminum sulfate (Al2(SO4)3?16 H2O, 97%) in 114.7 g of water, 6.6 g of tetra-propyl ammonium bromide (TPABr) to obtain a mixture. 84.89 g of a solution comprising sodium silicate (27wt% SiO2, 13.7% NaOH) in water was slowly added to the mixture to obtain a gel. The pH of the gel was adjusted to 10 by adding 19 g of 1:1 sulfuric acid (9.5 g water and 9.5 g sulfuric acid) to obtain a pH adjusted gel. The pH adjusted gel was further stirred continuously at room temperature for 2 hours to obtain a homogenous gel. The homogeneous gel was then transferred into an autoclave and was digested by heating at 110 ?C for 17 hours under stirring to obtain a digested gel. 22.2 g of a solution comprising 42.5 wt% dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (DMOD), 8 wt% 3-chloropropyl)trimethoxysilane and 49.5 wt% methanol were added to the digested gel to obtain a homogeneous mixture. The homogeneous mixture was then subjected to hydrothermal treatment by heating at 165 ?C under stirring for 48 hours to obtain a solid mass.
The solid mass was washed with water till the pH became 7 followed by drying at 120 ?C for 16 hours to obtain a dried solid mass. The dried solid mass was calcined at 540 ?C for 16 hours to obtain zeolitic mass.
XRD patterns of the dried and zeolitic mass confirmed ZSM-5 without any impurity. The zeolitic mass was analyzed for surface area and pore volume. The BET surface area was 421 m2/g and a pore volume was 0.45 ml/g.
The zeolitic mass prepared was Na-ZSM-5. The Na+ ions of Na-ZSM-5 were exchanged with NH4+ by treating in an aqueous solution of 1 M NH4NO3 at 80 °C for 3 hours. The NH4+ exchanged form of ZSM-5 was calcined in air at 540 °C for 6 hours to obtain H-ZSM-5.

Compositing of ZSM-5 SAR 110 with Al2O3: 32.9 g Condia alumina (having LOI 27 wt.%), 1.0 g HPMC and 74.0 g zeolitic mass were mixed thoroughly in a mortar-pastel to obtain a powder. 49.2 g aqueous solution comprising 3.7% acetic acid was added to the powder to obtain a semi-solid mass, which was extruded through an extruder to obtain extrudates. Extrusion was carried out using a 1.5 mm die. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours in air. The dried extrudates were calcined at 540 °C for 6 hours under air to obtain the catalyst composite. The catalyst composite contain 70% by weight of the zeolite.

Physical properties of the ZSM-5 zeolites prepared in experiments 1 to 5
The physical properties of ZSM-5 zeolites prepared in experiments 1 to 5 are summarized in Table 1.

Table 1: Physical properties of ZSM-5 zeolites prepared in experiments 1 to 5
Experiment 1 2 3 4 5
Silica to Alumina Mole Ratio (SAR) 40 80 100 108 108
Surface Area, m2/g 395 386 385 432 421
Total PV, ml/g 0.23 0.20 0.21 0.40 0.45
Meso PV, ml/g 0.12 0.11 0.13 0.33 0.37
Average Pore Width, ? 22 21 22 37 43
SAR: silica to alumina ratio, PV: pore volume

From Table 1, it is observed that ZSM-5 zeolites prepared by the method of present disclosure (Experiments 4 and 5) exhibit higher surface area, total pore volume, meso pore volume and average pore width as compared to the zeolites prepared using conventional method (Experiments 1, 2 and 3), even with higher silica to alumina ratio (SAR). The zeolite prepared using the conventional method (Experiment 3) having silica to alumina ratio of 100 exhibit surface area of 385 m2/g, total pore volume of 0.21 mL/g, meso pore volume of 0.13 mL/g and average pore width of 22 Å, whereas, the zeolite prepared using the present disclosure (Experiment 4) having silica to alumina ratio of 108 exhibit surface area of 432, total pore volume of 0.40 mL/g, meso pore volume of 0.33 mL/g and average pore width of 37 Å.

Experiment 6: Catalytic performance of the catalyst composites prepared in experiments 1, 2, 3, 4 and 5
The catalyst composites prepared in experiments 1 to 5 were evaluated for removal of olefin from deheptanizer bottom hydrocarbon stream comprising commercial C8+ aromatic stream.
The composition of the deheptanizer bottom hydrocarbons stream is given in Table 2.

Table 2: Composition of deheptanizer bottom hydrocarbon stream
Component wt.%
Non-aromatics 1.3
Toluene 1.56
Ethyl benzene 8.31
Xylenes 44.51
C9Aromatics 36.23
C10A + Heavy Aromatics 8.09

The procedure for the catalyst evaluation was as follows:
5 g of the extrudates of the catalyst composites were added to 35 g of commercial deheptanizer column bottom hydrocarbon stream in a stainless steel reactor. The reactor was purged with nitrogen to remove air and was closed. The reactor was heated at 200 °C to obtain a product stream. The reactor was allowed to cool to room temperature. The product stream was separated from the solid catalyst, and was analyzed for the presence of olefin impurity. Olefin concentration of the hydrocarbon stream and the product was determined as Bromine Index (BI) following American Standard Testing Method ASTM D-1491. Percent Olefin Conversion (i.e., Percent BI reduction was calculated as: (BI of Feed*100)/(BI of Feed – BI of Product). The results are summarized in Table 3.

Table 3: Results for reducing olefin content of a hydrocarbon stream using catalyst composites of experiments 1 to 5
Exp. No. Reaction Conditions Bromine Index (BI) % BI Reduction (Olefin Conversion)
Temp., °C Time, hour(s) Feed BI Product
BI
1
(Comparative) 180 3 602 485 19.4
2
(Comparative) 180 3 601 489 18.6
3
(Comparative) 180 3 603 502 16.7
4
(Present Disclosure) 180 3 601 399 33.6
5
(Present Disclosure) 180 3 602 376 37.5

From Table 3, it is clear that the catalyst composites prepared using the method of present disclosure (Experiments 4 and 5) exhibit better catalytic activity as compared to the catalyst composites prepared using conventional methods (Experiments 1, 2 and 3).

Experiment 7: Synthesis of ZSM-5 zeolite and compositing with aluminophosphate hydrogel
The zeolitic mass (ZSM-5 zeolite) was prepared using the procedure of Experiment 1.
Compositing ZSM-5 with aluminophosphate hydrogel: 20.6 g Condia alumina was taken in a beaker and 30.7 g demineralized water was added to it and stirred with a magnetic stirrer for 10 minutes to obtain a slurry. 34.0 g H3PO4 was added drop wise to the slurry to obtain a gel comprising aluminophosphates. 26.0 g demineralized water was added to the gel and stirred for 10 minutes to obtain a homogeneous gel. The homogeneous gel was added to the mixture of 1.5 g HPMC and 96.0 g of zeolitic mass (ZSM-5 zeolite) along with 10 g demineralized water to obtain a semi-solid mass. The semi-solid mass was extruded using 1.5 mm die to obtain extrudates. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours to obtain dried extrudates. The dried extrudates were calcined at 540 °C for 6 hours under air to obtain the catalyst composite. The catalyst composite contains zeolite of 70% by weight.

Experiment 8: Preparation of ZSM-5 zeolite and compositing with aluminophosphate hydrogel
The zeolitic mass (ZSM-5 zeolite) is prepared using the procedure of Experiment 3.
Compositing ZSM-5 zeolite with aluminophosphate: 20 g Condia alumina was taken in a beaker and 34 g demineralized water was added to it and stirred with magnetic stirrer for 10 minutes to obtain a gel. 34 g H3PO4 was added drop wise to the slurry to obtain a gel. 26 g demineralized water was added into the gel and stirred for another 10 minutes to obtain a homogeneous gel. The homogeneous gel was added to a mixture of 1.5 g HPMC and 96 g of zeolitic mass (H-ZSM-5 zeolite) powder along with 10 g demineralized water to obtain a semi-solid mass. The semi-solid mass was extruded using 1.5 mm die to obtain extrudates. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours. The dried extrudates were calcined at 540 °C for 6 hours under flowing air to obtain the catalyst composite. The catalyst composite contained 70% by weight of zeolite.
Experiment 9: Synthesis of ZSM-5 zeolite and compositing with aluminophosphate hydrogel
The zeolitic mass (ZSM-5 zeolite) was prepared using the procedure of Experiment 4.
Compositing ZSM-5 zeolite with aluminophosphate hydrogel: 12.9 g Condia alumina was taken in a teflon beaker and 10 g demineralized water was added to it and stirred with a magnetic stirrer for 10 minutes to obtain a slurry. 21.3 g H3PO4 was added drop wise to the slurry to obtain a gel. 10 g demineralized water was added to the gel and was stirred for 10 minutes to obtain a homogeneous gel. The homogeneous gel was added to a mixture of 1 g HPMC and 72.9 g of ZSM-5 zeolite along with 10 g of demineralized water to obtain a semi-solid mass. The semi-solid mass was extruded using 1.5 mm die to obtain extrudates. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours. The dried extrudates were calcined at 540 °C for 6 hours under flowing air to obtain the catalyst composite. The catalyst composite contained 70% by weight of zeolite.
Experiment 10: Synthesis of ZSM-5 zeolite and compositing with aluminophosphate hydrogel
The zeolitic mass (ZSM-5 zeolite) is prepared using the procedure of Experiment 5.
Compositing with aluminophosphate hydrogel: : 12.9 g Condia alumina was taken in a beaker and 10 g demineralized water was added to it and stirred with a magnetic stirrer for 10 minutes to obtain a slurry. 21.3 g H3PO4 was added drop wise to the slurry to obtain a gel, which was mixed with 10 g demineralized water to obtain a homogeneous gel. The homogeneous gel was then added to a mixture of 1.0 g HPMC and 69.4 g of zeolitic mass (H-ZSM-5 zeolite) powder along with 9.8 g water to obtain a semi-solid mass. The semi-solid mass was extruded using 1.5 mm die to obtain extrudates. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours to obtain dried extrudates. The dried extrudates were calcined at 540 °C for 6 hours under air to obtain the catalyst composite. Zeolite content in the catalyst composite was 70% by weight.

Experiment 11: Catalytic performance evaluation of catalyst composites prepared in Experiments 7 to 10
The catalyst composites prepared in experiments 7 to 10 were evaluated for removal of olefins from a hydrocarbon stream. The results are summarized in Table 4.

Table 4: Results of catalytic performance (reduction in olefin content) evaluation of catalyst composites prepared in Experiments 7 to 10
Exp. No. Reaction Conditions BI % BI Reduction (% Olefin Conversion)
Temp., °C Time, hour(s) Feed Product
7 (Comparative) 180 3 602 481 20.1
8 (Comparative) 180 3 600 534 11
9 (Present disclosure) 180 3 601 342 43.1
10 (Present disclosure) 180 3 600 376 37.2

From Table 4, it is observed that the catalyst composites prepared using the process of the present disclosure, exhibit better performance for reduction of olefins from the hydrocarbon stream.

Experiment 12: Synthesis of ZSM-5 zeolite and compositing with Al2O3
A solution of 11.72 g sodium hydroxide in 588.6 g of water, 5.2 g of aluminum sulfate hexadecahydrate ((Al2(SO4)3.16H2O, 97%) 20.89 g tetra-propylammoniumbromide (TPABr) were added to a reactor under stirring to obtain a mixture. To the mixture was added 155.5 g of Ludox AM30 slowly to obtain a gel having pH 12.7. The gel was stirred continuously at room temperature for 2 hours to obtain a homogeneous mixture having the molar composition as. 18.3 Na2O : 97 SiO2 : 1 Al2O3 : 9.8 TPABr : 4859 H2O.
The homogeneous mixture was transferred to an autoclave and was subjected to hydrothermal treatment at 165 ?C under stirring for 48 hours to obtain a solid mass. The solid mass was washed with water till pH became 7 followed by drying at 120 ?C for 16 hours to obtain a zeolitic mass.
The zeolitic mass was calcined at 540 ?C for16 hours to obtain calcined zeolitic mass, ZSM-5 zeolite. The BET surface area of the ZSM-5 zeolite was 382 m2/g and the pore volume was 0.26 ml/g.
The zeolite prepared was Na-ZSM-5. The Na+ ions of Na-ZSM-5 were exchanged with NH4+ by treating in an aqueous solution of 1 M NH4NO3 at 80 °C for 3 hours. The NH4+ exchanged form of ZSM-5 was calcined in air at 540 °C for 6 hours to obtain H-ZSM-5.

Compositing ZSM-5 with Al2O3:
19.9 g Condia alumina (having LOI 27 wt.%), 0.6 g HPMC and 41.9 g calcined zeolitic mass (ZSM-5) were mixed thoroughly in a mortar-pastel to obtain a powder. 26.9 g aqueous solution comprising 3.7% acetic acid was added to the powder to obtain a semi-solid mass, which was extruded through an extruder using 1.5 mm die to obtain extrudates. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours in air to obtain dried extrudates. The dried extrudates were calcined at 540 °C for 6 hours under air to obtain a catalyst composite. Zeolite content in the catalyst composite was 70% by weight.

Experiment 13: Synthesis of ZSM-5 and compositing with Al2O3
44.6 g of a solution comprising 42.5% dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (DMOD) 8 wt% (3-chloropropyl)trimethoxysilane, 49.5 wt% methanol, 11.3 g of sodium hydroxide, 12.5 g of aluminium sulfate hexadecahydrate (Al2(SO4)3?16 H2O, 97%), 20.2 g of tetra-propyl-ammonium bromide (TPABr) was mixed with 566 g of water to obtain a mixture. To the mixture was added 150.6 g of Ludox AM30 slowly to obtain a gel having pH of 12.7. The gel was further stirred continuously at room temperature for 2 hours to obtain a homogeneous mixture having the molar composition as 7.3 Na2O : 42.1 SiO2 : 1 Al2O3 : 3.9 TPABr : 1960.4 H2O : 35.9 CH3OH.
The homogeneous mixture was transferred to an autoclave and was subjected to hydrothermal treatment at 165 ?C under stirring for 48 hours to obtain a solid mass. The solid mass was washed with water till pH became 7 and dried at 120 °C for 16 hours to obtain a zeolitic mass. The dried solid mass was calcined at 540 °C for 16 hours to obtain a zeolitic mass. The BET surface area of the zeolitic mass was 354 m2/g and pore volume was 0.36 ml/g.
The zeolitic mass prepared was Na-ZSM-5. The Na+ ions of Na-ZSM-5 were exchanged with NH4+ by treating in an aqueous solution of 1 M NH4NO3 at 80 °C for 3 hours. The NH4+ exchanged form of ZSM-5 was calcined in air at 540 °C for 6 hours to obtain H-ZSM-5.

Compositing zeolite with Al2O3: 28.8 g Condia alumina (having LOI 27 wt.%), 0.9 g HPMC and 65.3 g zeolitic mass were mixed thoroughly in a mortar-pastel. 36.9 g aqueous solution comprising 3.7% acetic acid was added to powder to obtain a semi-solid mass. Extrusion of the semi-solid mass was done using a 1.5 mm die to obtain extrudates. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours in air to obtain dried extrudates. The dried extrudates were calcined at 540 °C for 6 hours under air. Zeolite content in the catalyst composite was 70% by weight.

Experiment 14: Synthesis of ZSM-5 zeolite and compositing with Al2O3
A solution comprising 44.6 g of 42.5% dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (DMOD), 8 wt% (3-chloropropyl)trimethoxysilane and 49.5 wt.% methanol in 569 g of water, 11.3 g of sodium hydroxide, 6.3 g of aluminium sulfate hexa-deca hydrate (Al2(SO4)3?16 H2O, 97%) , 20.2 g of tetrapropylammonium bromide were charged in a reactor to obtain a mixture. 150.6 g of Ludox AM30 was slowly added to the mixture to obtain a gel having pH of 12.7. The gel was stirred continuously at room temperature for 2 hours to obtain a homogeneous mixture having the molar composition as 14.5Na2O: 83.5SiO2: 1Al2O3: 7.8 TPABr: 3882.5 H2O: 71.2 CH3OH.
The homogeneous mixture was transferred to an autoclave and was subjected to hydrothermal treatment at 165 ?C under stirring for 48 hours to obtain a solid mass. The solid mass was washed with water till pH became 7 and dried at 120 oC for 16 hours to obtain a dried solid mass. The dried solid mass was calcined at 540 °C for 16 hours to obtain zeolitic mass. The XRD pattern of the zeolitic mass indicated the presence of a single phase of ZSM-5. The BET surface area of zeolitic mass was 411 m2/g and pore volume was 0.4 ml/g.
The zeolitic mass prepared was Na-ZSM-5. The Na+ ions of Na-ZSM-5 were exchanged with NH4+ by treating in an aqueous solution of 1 M NH4NO3 at 80 °C for 3 hours. The NH4+ exchanged form of ZSM-5 was calcined in air at 540 °C for 6 hours to obtain H-ZSM-5.

Compositing with alumina: 28.8 g Condia alumina (having LOI 27 wt.%), 0.9 g HPMC and 65.3 g zeolitic mass were mixed thoroughly in a mortar-pastel to obtain a powder. 36.9 g aqueous solution comprising 3.7% acetic acid was added to the powder to obtain a semi-solid mass. The semi-solid mass was extruded using a 1.5 mm die to obtain extrudates. Extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours in air to obtain dried extrudates. The dried extrudates were calcined at 540 °C for 6 hours under air to obtain the catalyst composite. The catalyst composite contained 70% by weight of zeolite.

Experiment 15: Synthesis of ZSM-5 and compositing with Al2O3
A solution comprising 44.6 g of 42.5% dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, 8 wt% of (3-chloropropyl)trimethoxysilane and 49.5 wt.% methanol in 570 g of water, 11.3 g of sodium hydroxide, 5 g of aluminium sulfate hexa-deca-hydrate (Al2(SO4)3?16 H2O, 97%) and 20.2 g of tetra-propyl ammonium bromide (TPABr) were mixed in a beaker to obtain a mixture. 150.6 g of Ludox AM30 was slowly added to the mixture to obtain a gel having pH of 12.7. The gel was further stirred continuously at room temperature for 2 hours to achieve a homogeneous mixture having the molar composition as 18.3Na2O : 105 SiO2 : 1Al2O3 : 9.9 TPABr : 4895 H2O : 89.6 CH3OH.
The homogeneous mixture was transferred into an autoclave and was subjected to hydrothermal treatment at 165 ?C under stirring for 48 hours to obtain a solid mass. The solid mass was washed with water till pH 7 and dried at 120 oC for 16 hours to obtain a dried solid mass. The dried solid mass was calcined at 540 °C for 16 hours to obtain a zeolitic mass, ZSM-5 zeolite. The BET surface area of zeolite was 432 m2/g and pore volume was 0.39 ml/g.
The zeolitic mass prepared was Na-ZSM-5. The Na+ ions of Na-ZSM-5 were exchanged with NH4+ by treating in an aqueous solution of 1 M NH4NO3 at 80 °C for 3 hours. The NH4+ exchanged form of ZSM-5 was calcined in air at 540 °C for 6 hours to obtain H-ZSM-5.

Compositing with alumina: 28.8 g Condia alumina (having LOI 27 wt.%), 0.9 g HPMC and 65.3 g zeolitic mass (H-ZSM-5 zeolite) were mixed thoroughly in a mortar-pastel to obtain a powder. 35.6 g aqueous solution comprising 3.7% acetic acid was added to the powder to obtain a semi-solid mass. The semi-solid mass was extruded through an extruder wherein the extrusion was done using a 1.5 mm die to obtain extrudates. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours in air to obtain dried extrudates. The dried extrudates were calcined at 540 °C for 6 hours under air to form the catalyst composite. The catalyst composite contain zeolite of 70% by weight.

Properties of ZSM-5 zeolite prepared according to method of present invention and comparison of those with ZSM-5 prepared by conventional method.
The properties of ZSM-5 zeolites prepared according to the processes as described in experiments 12 to 15 are summarized in Table 5.

Table 5: Properties of ZSM-5 zeolites prepared in experiments 12 to 15
Exp. No. 12
(Comparative) 13
(Present Disclosure) 14
(Present Disclosure) 15
(Present Disclosure)
SAR (silica to alumina ratio) 97 42 83 105
surface Area, m2/g 382 354 411 432
Total Pore Volume, mL/g 0.26 0.36 0.4 0.39
Micro-Pore Volume, ml/g 0.11 0.08 0.1 0.08
Meso-Pore Volume, ml/g 0.15 0.28 0.3 0.31
Average Pore Width, ? 26.8 41 38.3 36

From Table 5, it is clear that, zeolites prepared using the process of the present disclosure exhibit higher surface area, higher meso-pore volume, and higher average pore width as compared to the zeolite prepared by the conventional process.

Experiment 16: Catalytic performance evaluation of zeolites prepared in experiments 12 to 15
The results obtained for reduction of olefins from the deheptanizer bottom stream are summarized in Table 6.

Table 6: Performance evaluation of catalyst composites for olefin removal from hydrocarbon stream
Experiment Number Reaction Conditions Results % BI Reduction (Olefin Conversion)
Temp., °C Time, hour Feed BI Product BI
12
(Comparative) 180 3 602 538 10.6
13
(Present disclosure) 180 3 600 386 35.7
14
(Present disclosure) 180 3 601 405 32.6
15
(Present disclosure) 180 3 603 390 35.3

From Table 6, it is observed that remarkable improvement in olefin reduction level with the zeolite prepared by the process of present disclosure is clearly noted as compared to the olefin reduction achieved using the catalyst composite prepared using the conventional processes.

Experiment 17 (Comparative): Synthesis of ZSM-5 zeolite and compositing with aluminophosphates
The zeolitic mass was prepared as per the procedure provided in Experiment 12.
Compositing with aluminophosphates: 8.1 g Condia alumina was taken in a beaker and 5 g demineralized water was added to it and stirred with a magnetic stirrer for 10 minutes to obtain a slurry. 13.3 g H3PO4 was added drop wise to the slurry to form a gel. Gel was mixed with 10 g demineralized water under stirring to obtain a homogeneous gel. The homogeneous gel was mixed with a mixture of 0.6 g HPMC and 40.6 g ZSM-5 to obtain a semi-solid mass. The semi-solid mass was extruded using a 1.5 mm die to obtain extrudates. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours to obtain to obtain dried extrudates. The dried extrudates were calcined at 540 °C for 6 hours under air to the catalyst composite. The catalyst composite contained 70% by weight of zeolite.
Experiment 18 (Present disclosure): Synthesizing zeolite and compositing with aluminophosphates
The zeolitic mass (ZSM-5 zeolite) was prepared as per the procedure of Experiment 13.
Compositing with aluminophosphates: 10.3 g Condia alumina was taken in a beaker and 20.2 g demineralized water was added to it and stirred with a magnetic stirrer for 10 minutes to obtain a slurry. 17.0 g H3PO4 was added drop wise to above slurry to form a gel. Gel was mixed with 13.2 g demineralized water to obtain a homogeneous gel. The homogeneous gel was mixed with a mixture of 1.0 g HPMC and 56.0 g of zeolitic mass (H-ZSM-5) to obtain a semi-solid mass. The semi-solid mass was extruded using a 1.5 mm die to obtain extrudates. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours to obtain dried extrudates. The dried extrudates were calcined at 540 °C for 6 hours under flowing air to obtain the catalyst composite. The catalyst composite contained 70% by weight of zeolite. .
Experiment 19 (Present disclosure): Synthesis of ZSM-5 zeolite and compositing with aluminophosphates
The zeolitic mass (ZSM-5 zeolite) was prepared as per the procedure of Experiment 13.
Compositing with aluminophosphates: 10.3 g Condia alumina was taken in a beaker and 20.4 g demineralized water was added to it and stirred with magnetic stirrer for 10 minutes to obtain a slurry. 17.0 g H3PO4 was added drop wise to above slurry to form a gel. Gel was mixed with 9.2 g demineralized water to obtain a homogeneous gel. The homogeneous gel was mixed with 1.0 g HPMC and 56.0 g of zeolitic mass (H-ZSM-5) to obtain a semi-solid mass. The semi-solid mass was extruded using 1.5 mm die to obtain extrudates. The extrudates were dried at room temperature for 1 hour followed by drying at 120 °C for 6 hours to obtain dried extrudates. The dried extrudates were calcined at 540 °C for 6 hours under flowing air to obtain the catalyst composite. The catalyst composite contained 70% by weight of zeolite.
Experiment 20: Catalytic performance evaluation of zeolite prepared in experiments 17 to 19
Table 7: Performance comparison of zeolite composites prepared in Experiments 17 to 19
Exp. No. Reaction Conditions Results % BI Reduction (Olefin Conversion)
Temp., °C Time, hour Feed BI Product BI
17
(Comparative) 180 3 602 533 11.5
18
(Present Disclosure) 180 3 600 357 40.4
19
(Present Disclosure) 180 3 601 383 36.3

From Table 7, it is observed that remarkable improvement in olefin reduction level with the zeolite prepared by the process of present disclosure is clearly noted as compared to the olefin reduction achieved using the catalyst composite prepared using the conventional processes.
TECHNICAL ADVANCES AND ECONOMICAL SIGNIFICANCE
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a process of preparation of a catalyst composite for reducing olefins from a hydrocarbon stream, that:
- has high surface area, pore volume and average pore width; and
- provides higher olefin reduction, when used for reducing olefins from the hydrocarbon stream.

The foregoing description of the specific embodiments so fully reveals the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.