Claims:1. A process of manufacturing potassium humate flakes from Leonardite comprising the steps of: (a) grinding the Leonardite to fine powder; (b) dissolving the powder in a solution of potassium hydroxide at 60°C to 90°C for 3 hours to 6 hours; (c) mixing ethylenediaminetetraacetic acid to step (b); (d) centrifuging to separate the insolubles and supernatant; and (e) settling the supernatant for 6 hours to 12 hours, followed by drying in drum dryers at 100°C to 200°C to give potassium humate flakes.

2. The process as claimed in claim 1, wherein the Leonardite is sourced as Leonardite lumps and are ground to fine powder of mesh 80 to 120.

3. The process as claimed in claim 1, wherein the solution of potassium hydroxide is a 8% to 14% solution of potassium hydroxide in water.

4. The process as claimed in claim 1, wherein the dissolution of powdered Leonardite in the solution of potassium hydroxide is performed at 80°C for 4 hours.

5. The process as claimed in claim 1, wherein the ethylenediaminetetraacetic acid is a 1-2% powder of ethylenediaminetetraacetic acid.

6. The process as claimed in claim 1, wherein the centrifugation of step (d) is performed at high speeds in the range of 1700 to 2400.

7. The process as claimed in claim 1, wherein the supernatant is settled for 6 hours in step (e).

8. The process as claimed in claim 1, wherein the drying is carried out at a temperature range of 140°C to 180°C.
9. The process as claimed in claim 1, wherein the potassium humate flakes comprise 45% to 70% humic acid and 8% to 10% potassium oxide.

10. The process as claimed in claim 1, wherein the pH of the process is maintained in the range of 8 to 11.
, Description:FIELD OF THE INVENTION
[0001] The present disclosure relates generally to chemical synthesis. More specifically, the disclosure is directed to a process of manufacturing potassium humate flakes from Leonardite.

BACKGROUND OF THE INVENTION
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] Humic acid is a natural, multi-functional, high molecular weight organic compound. Potassium and humic acid are both very essential components for plant growth. Potassium humate is the potassium salt of humic acid with a complex mixture of structures, commonly used as an additive for plant health. It acts as a great biostimulant which enhances soil quality and plant growth; and may be fed to plant and soils as manure. Apart from its use in agriculture, humic acid may also be employed in the industry for textiles and concrete manufacturing.
[0004] Humic acid occurs naturally in brown coal or lignite of coal deposits. Leonardite is the upper most layer of lignite and is very rich in humic acid. It is easily available in many parts of the world, but is mainly sourced from China. Since potassium hydroxide is ordinarily used for extraction of humic acid the salts obtained from the extraction process is potassium humate. Extraction of humic acid from Leonardite is well known, however, the presence of impurities, including humin and fulvic acid, can make the extraction process tedious. Current manufacturing processes used to manufacture potassium humate involve settlement of reactant liquid for over 24 hours, which makes the overall process long and consequently more expensive.
[0005] Thus, there is a need in the art to look for alternate processes for manufacture of potassium humate that are less time consuming and economic.

OBJECTS OF THE INVENTION
[0006] An object of the present disclosure is to provide a process for manufacturing potassium humate flakes from Leonardite.
[0007] An object of the present disclosure is to provide a process of manufacturing potassium humate flakes that is economic and requires less time.
[0008] Another object of the present disclosure is to provide a process of manufacturing potassium humate flakes that is commercially viable.

SUMMARY OF THE INVENTION
[0009] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in Detailed Description section. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
[0010] Aspects of the present disclosure provide a commercially viable process of manufacturing potassium humate flakes from Leonardite, the upper layer of lignite.
[0011] In an aspect, the present disclosure provides a process of manufacturing potassium humate flakes from Leonardite comprising the steps of: (a) grinding the Leonardite to fine powder; (b) dissolving the powder in a solution of potassium hydroxide at about 60°C to about 90°C for about 3 hours to about 6 hours; (c) mixing ethylenediaminetetraacetic acid to step (b); (d) centrifuging to separate the insolubles and supernatant; and (e) settling the supernatant for about 6 hours to about 12 hours, followed by drying in drum dryers at about 100°C to about 200°C to give potassium humate flakes.
[0012] In an embodiment, the solution of potassium hydroxide may be a solution of potassium hydroxide in water.
[0013] In an embodiment, the dissolution of powdered Leonardite in the solution of potassium hydroxide may be performed at about 80°C for about 4 hours.
[0014] In an embodiment, the ethylenediaminetetraacetic acid may be a 1-2% powder of ethylenediaminetetraacetic acid.
[0015] In an embodiment, the supernatant is collected in a collection tank and left to settle, preferably for about 6 hours.
[0016] In an embodiment, the potassium humate flakes comprise about 45% to about 70% humic acid and about 8% to about 10% potassium oxide.
[0017] In an embodiment, the process may provide potassium humate flakes in yield of about 75% to about 85%.
[0018] In an aspect, the present disclosure also provides potassium humate flakes obtained by a process comprising the steps of: (a) grinding the Leonardite to fine powder; (b) dissolving the powder in a solution of potassium hydroxide at about 60°C to about 90°C for about 3 hours to about 6 hours; (c) mixing ethylenediaminetetraacetic acid to step (b); (d) centrifuging to separate the insolubles and supernatant; and (e) settling the supernatant for about 6 hours to about 12 hours, followed by drying in drum dryers at about 100°C to about 200°C to give potassium humate flakes.
[0019] Other aspects of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learnt by the practice of the invention.

DETAILED DESCRIPTION OF THE INVENTION
[0020] The following is a detailed description of embodiments of the disclosure. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0021] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0022] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0023] In some embodiments, numbers have been used for quantifying weights, percentages, ratios, and so forth, to describe and claim certain embodiments of the invention and are to be understood as being modified in some instances by the term “about.” Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[0024] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[0025] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0026] Unless the context requires otherwise, throughout the specification which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense that is as “including, but not limited to.”
[0027] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein.
[0028] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[0029] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified.
[0030] The description that follows, and the embodiments described therein, is provided by way of illustration of an example, or examples, of particular embodiments of the principles and aspects of the present disclosure. These examples are provided for the purposes of explanation, and not of limitation, of those principles and of the disclosure.
[0031] It should also be appreciated that the present disclosure can be implemented in numerous ways, including as a system, a method or a device. In this specification, these implementations, or any other form that the invention may take, may be referred to as processes. In general, the order of the steps of the disclosed processes may be altered within the scope of the invention.
[0032] The headings and abstract of the invention provided herein are for convenience only and do not interpret the scope or meaning of the embodiments.
[0033] The following discussion provides many example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.
[0034] In an embodiment, the present disclosure provides a process of manufacturing potassium humate flakes from Leonardite.
[0035] In an embodiment, the present disclosure provides a process of manufacturing potassium humate flakes from Leonardite comprising the steps of: (a) grinding the Leonardite to fine powder; (b) dissolving the powder in a solution of potassium hydroxide at about 60°C to about 90°C for about 3 hours to about 6 hours; (c) mixing ethylenediaminetetraacetic acid to step (b); (d) centrifuging to separate the insolubles and supernatant; and (e) settling the supernatant for about 6 hours to about 12 hours, followed by drying in drum dryers at about 100°C to about 200°C to give potassium humate flakes.
[0036] In an embodiment, the Leonardite may be sourced as Leonardite lumps which are ground to fine powder in step (a). In an embodiment, the Leonardite lumps may be ground to fine powder of mesh 80 to 120. In a preferred embodiment, the Leonardite lumps may be ground to fine powder of 100 mesh.
[0037] In an embodiment, the fine powder of Leonardite must have less than 20% moisture.
[0038] In a preferred embodiment, the grinding may be performed in a pulverizer.
[0039] In an embodiment, the solution of potassium hydroxide may be a solution of potassium hydroxide in water. In an embodiment, the solution of potassium hydroxide may be about 8% to about 14% solution of potassium hydroxide in water, preferably about 10% solution of potassium hydroxide in water.
[0040] In a preferred embodiment, the dissolution of powdered Leonardite in the solution of potassium hydroxide may be performed at about 80°C for about 4 hours.
[0041] In an embodiment, the ethylenediaminetetraacetic acid may be a 1-2% powder of ethylenediaminetetraacetic acid. Ethylenediaminetetraacetic acid increases the chelation of humic acid and consequently increases its extraction from Leonardite. It also enhances the reaction time and makes the reaction faster.
[0042] In an embodiment, the centrifugation of step (d) may be performed at high speeds in the range of about 1700rpm to about 2400rpm. This separates out all the insolubles, for example humin, to give the supernatant. The insoluble solid may be either discarded or may be recycled to reaction vessel for further reaction.
[0043] In an embodiment, the supernatant is collected in a collection tank and left to settle. In an embodiment, the time for settling may be about 6 hours. This process therefore overcomes the need of settling times of about 24 hours in conventional processes.
[0044] The supernatant upon drying in drum dryers gets converted to potassium humate flake. In an embodiment, the drying may be carried out at a temperature range of about 140°C to about 180°C.
[0045] In an embodiment, the potassium humate flakes obtained from the process as recited above are shiny black in color. In an embodiment, the potassium humate flakes comprise about 45% to about 70% humic acid and about 8% to about 10% potassium oxide.
[0046] In an embodiment, pH of the process may be maintained in the range of 8 to 11.
[0047] The process of the present disclosure provides high yields. In an embodiment, the process may provide potassium humate flakes in yield of about 75% to about 85%. Thus, the process of the present disclosure overcomes the low yields of 60% to 70% generated by processes conventionally used.
[0048] The process is simple, economically viable and industrially scalable. The present disclosure addresses the high manufacturing costs and time required for processes extracting potassium humate from Leonardite.
[0049] In an embodiment, the present disclosure provides potassium humate flakes obtained by a process comprising the steps of: (a) grinding the Leonardite to fine powder; (b) dissolving the powder in a solution of potassium hydroxide at about 60°C to 90°C for about 3 hours to 6 hours; (c) mixing ethylenediaminetetraacetic acid to step (b); (d) centrifuging to separate the insolubles and supernatant; and (e) settling the supernatant for about 6 hours to 12 hours, followed by drying in drum dryers at about 100°C to 200°C to give potassium humate flakes.
[0050] In an embodiment, the potassium humate flakes obtained from the present disclosure may be employed in agriculture as a biostimulant to increase soil quality and plant growth. In an embodiment, the potassium humate flakes also improve the efficiency of fertilizers used on the crops. In some embodiments, the potassium humate flakes may be mixed with fertilizers, manure or compost for use.
[0051] The potassium humate flakes produced by the process facilitate transport, as well as storage unlike liquid forms of humic acid which are difficult to transport.
[0052] While the foregoing describes various embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.
EXAMPLES
[0053] The disclosure will now be illustrated with working examples, which is intended to illustrate the working of disclosure and not intended to take restrictively to imply any limitations on the scope of the present disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this disclosure belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice of the disclosed methods and compositions, the exemplary methods, devices and materials are described herein. It is to be understood that this disclosure is not limited to particular methods, and experimental conditions described, as such methods and conditions may vary.
[0054] MATERIALS: Leonardite was obtained from a soil in the People’s Republic of China.
[0055] EXAMPLE 1
[0056] Leonardite lumps were ground to fine powder of 100Mesh and less than 20% moisture using a pulverizer. This powder was dissolved in a 10% solution of potassium hydroxide in water in a reaction vessel at 80°C for four hours. 1-2% ethylenediaminetetraacetic acid powder was added in this mixture to increase the chelation and extraction of humic acid. This solution was then passed through high speed centrifuge where insolubles got separated. The liquid from centrifuge was then collected in a collection tank and left to settle for about 6 hours. The supernatant liquid was then passed through Drum Dryers where it got converted into potassium humate flakes at 140 – 180°C. The final product was shiny black flakes of potassium humate which had around 60% Humic Acid and 8-10% K2O. The yield of potassium humate flakes was 85%.
[0057] From the foregoing, it will be appreciated that, although specific embodiments of the invention have been described herein merely for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention and should not be construed so as to limit the scope of the invention or the appended claims in any way.

ADVANTAGES OF THE PRESENT INVENTION
[0058] The present disclosure provides a process of manufacturing potassium humate flakes which requires less time and generates higher yield.
[0059] The present disclosure provides a process of manufacturing potassium humate flakes that is industrially scalable and commercially viable.
[0060] The present disclosure provides a process of manufacturing potassium humate flakes that is economic.