DESC:FIELD OF THE INVENTION

The present invention relates to the bio-based densified material, process of making same, and use thereof. More preferably, the present invention is providing a densified biomass based packaging composition, consisting of: densified biomass having bulk density range between 0.4 g/cm3 and 0.6 g/cm3 and that of the calorific values range between 3000 Cal/g and 4500 Cal/g.and process of preparation thereof. The modified process for preparation of bio-based densified material having properties that will make such material suitable for applications like textiles, insulation, packaging, fuel, owing to its bio-degradable nature, strong mechanical performance, and considerable calorific value. The present invention is providing a modified process of converting any biomass into a highly densified material in the form of blocks/sheets/balls/pellets at atmospheric pressure and without addition of any external binding agent.

PRIOR ART DISCUSSION
Biomass is a potential source of renewable energy. One of the major barriers to its widespread use is that biomass has a lower energy content than traditional fossils fuels, which means that more fuel is required to get the same amount of energy as relation of low energy content with low density. Therefore, the volume of biomass handled increases enormously. Further, biobased insulation materials are crucial for replacement of petroleum feedstock based synthetic polyurethane and polystyrene based materials from sustainability perspective. However, manufacturing of biobased insulation materials involves tedious solid handling operations that incur high production costs.
Compaction or densification is one way to increase the energy density and overcome handling difficulties. Through various densification technologies, raw biomass is compressed to densities in the order of 7–100 times its original bulk density.
The main advantages of biomass densification are:
• Increased energy density with high densified material,
• Uniform combustion rate
• Reduced dust production
• Simplified storage and handling infrastructure, lowering capital requirements
• Reduced cost of transportation due to increased energy density
Reported methods of manufacturing bio-based densified materials involve either bonding (by help of at least one binder, such as glue, to make one or more kinds of loose/particle materials to form a whole body) or pressing (by help of high pressing at environmental or elevated temperature). The tedious operations of handling low density solid material increase the manufacturing cost for biobased materials, and they fail to compete economically with synthetic materials like polyurethane and polystyrene for packaging applications or with fossil fuels for application as fuel. A methodology in which the reagents can be recycled completely, and process parameters are mild and do not require specialty equipment can make the process economics favorable for biobased densified materials.
Therefore, a major disadvantage to current biomass densification technologies is the high cost associated with some of the densification processes like drying to remove moisture, mechanical pressure providing instruments, application of binding agent, high temperature torrefaction/pyrolysis (above 250ºC).

IN 202241056678 discloses the process for hybrid bio-mass briquettes through the densification process using the temperature between 160°C and 220°C with applied pressure of about 5600 Psi. In such technique a high-pressure hydraulic machine is used to densify the green waste and the equipment is filled with three layers to make a single briquette. At this high pressure, the temperature rises to about 200 – 250 °C, which is sufficient to fuse the lignin content of the residue.

The closest literature to the invention is as follows: A strong, biodegradable and recyclable lignocellulosic bioplastic, Nature Sustainability. DOI: 10.1038/s41893-021-00702-w. This article proposes usage of deep eutectic solvent composed of choline chloride and oxalic acid to be used with biomass to yield bioplastics. But this process utilizes high temperature of above 80ºC. Further, the time required to more than 4 hours and utilization of deep eutectic solvent is 10 times higher than the biomass under treatment. The product of after the processing of biomass in this article is a film of biomass.
The inventors of present invention have developed a new process of densification and product obtained from that process wherein; the morphology of naturally available biomass (fresh/waste) was altered by providing a modified densification process by manipulating the hydrogen bonding between cellulose and lignin at atmospheric pressure and enabling formation of blocks/sheets/balls/pellets from any biomass samples consisting of loose particles.

SUMMARY OF THE INVENTION
The present invention is related to the development of dry densified biomass based packaging material using agro-wastes like wood saw dust, dry leaves, stocks, rice stalk, husk fiber and lignin based biomass wastes, with good calorific values and good packaging material behavior such as moisture resistance and compression strength.
The uniformly shredded dried bio-wastes (non-limiting dried under direct sun light over a period or using industrial drying process). The shredded and dried bio-mass components are chemically treated with solvents under specific temperature condition to obtain the densified material.
In accordance to first embodiment, the present invention provides a densified biomass based packaging composition, consisting of: densified biomass having bulk density range between 0.4 g/cm3 and 0.6 g/cm3 and that of the calorific values range between 3000 Cal/g and 4500 Cal/g.
In accordance to second embodiment, the present invention provides a process for preparing the densified biomass based packaging composition comprising the steps of:
(a) Pulverisation of dried biomass to form a size reduction of biomass, wherein size reduction of biomass is preferably between 2 to 20 mm.,
(b) Separately preparing a deep eutectic solvent at temperature between 35 to 60 °C and atmospheric pressure,
(c) Addition of step b) solvent to step a) biomass and increasing the temperature between 30 to 110 °C under constant stirring for time between 0.1 Hr to 10 Hr at atmospheric pressure,
(d) Addition of antisolvent at temperature between 30 to 110 °C under constant stirring for time between 0.1 Hr to 10 Hr at atmospheric pressure,
(e) Reducing the temperature to room temperature range between 20 to 35 °C,
(f) Filtration of step e) mass to separate a solvent using filter paper to obtain a wet densified biomass,
(g) Pouring the filtered biomass into a mould and drying under hot air oven at temperature between 60 to 110 °C to obtain a densified biomass based packaging composition,
(h) Tuning the porosity of the biomass based packaging composition using thermal treatment in a furnace under nitrogen at temperature between 200 to 600 °C.
In accordance to present invention, the deep eutectic solvent selected from the combination of Choline chloride -oxalic acid, Choline chloride- Urea, Zinc chloride- Urea, Choline chloride- ethylene glycol and more preferably a Choline chloride and oxalic acid in combination of weight ratio for Choline chloride and oxalic acid is between 0.1 to 10, more preferably 1:1.
In accordance to present invention, the antisolvent are selected from group of polar and protic solvents, wherein antisolvents are selected from water, ethanol, isopropyl alcohol, methanol and mixture thereof.
Further, the weight ratio of biomass to deep eutectic solvent is between 0.1 to 10, more preferably in weight proportion between 1:1 to 1:3.
Uniqueness of this technology are:
• No use of a single toxic chemical component.
• Developed in the atmospheric pressure.
• Do not need rapid human intervention .
• Channelling various biomass remains in a better way by generating very useful product for the end user as well as for the industry application.
• Completely recyclable technology.
• No waste generation.
• Regeneration and reuse of solvents used in the process.

DESCRIPTION OF THE DRAWING
For a more detailed understanding of the present invention, reference is made to the following description taken in conjunction with the accompanying drawing. It is to be understood; however, each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention.
Figure No. 1: Illustrates the process flow chart.
Figure No. 2: Illustrates the image of biomass collected from garden and prepared densified bio-based material thereof.
Figure No. 3: Illustrates the SEM image of rice stalk (a) and block made from rice stalk (b).
Figure No. 4: Illustrates the SEM image of garden waste (a) and block made from garden waste (b).
Figure No. 5: Illustrates the SEM image of the block made from a 50% (w/w) mixture of rice stalk and garden waste.
Figure No. 6: Illustrates the graph of compressive strength comparison of polystyere (plastic) and present invention composition (Blocks of rice stock, garden waste and mixture thereof) .

DETAILED DESCRIPTION OF THE INVENTION
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the term “composite",” “composition”, “material” and “matrix” are intended to include the form of material. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.

The present invention primary relates to a bio-based densified material comprising a composite comprising of cellulose and lignin which gives unique morphology to biomass. Further, the present invention also provides a composition of said composite along with some additives. The additives are available in between 0.001 to 20 % w/w, more preferably, between 0.001 to 10% w/w of total weight of said composite. The non-limiting examples of such additives include dyes, flame retardants, light and heat stabilizers, plasticizers, antistatic agents, pigments, anti-fungal agents, anti-microbial agents, Fragrances, oils, waxes, polymers etc.

Secondly, the present invention provides a process of making bio-based densified material, and use thereof. More preferably, the present invention is providing a bio-based densified material in the form of blocks, sheets, balls, pellets, films, sticks for applications like packaging, insulation, fuel in combustion plant, fuel for household etc.

It is one of the objectives of the present invention to provide a biomass densification process for preparation of bio-based renewable energy.
It is another objective of the present invention to provide a modified biomass densification process with various deep eutectic solvents by utilizing a lower temperature i.e. below 100 ºC.

It is also an objective of the present invention to provide a modified biomass densification process having less processing time.
The present invention provides a process for preparation of bio-based densified material as per figure 1, comprising steps of:
a) Collection of biomass and optionally performing a size reduction pre-treatment if required.
b) Addition of deep eutectic solvent to biomass and Reacting at temperature between 25 to 100ºC for time between 5 to 30 minute,
c) Addition of antisolvent and heating the reaction mass to temperature between 25 to 100ºC for time between 30 to 180 minutes,
d) Filtrating out a solid mass
e) Moulding the solid mass in different shape and drying at ambient temperature and curing in hot air oven
Further, the process involves steps for regeneration of deep eutectic solvent and antisolvent selected from non-limiting techniques like heating and condensation.
The non-limiting examples of biomass are selected from dry or wet form of wood, leaves, fruit kernels, husk, straw etc.
The non-limiting examples of deep eutectic solvents are selected from mixture of choline chloride and oxalic acid, zinc chloride and urea, choline chloride and urea, choline chloride and glycerol, or combination thereof.
The ratio of DES to biomass is selected between 5:1, 3.5:1 and 1:1.
The non-limiting examples of antisolvent are selected water, protic solvents like ethanol and combination thereof.

In accordance to first embodiment, the present invention provides a densified biomass based packaging composition, consisting of: densified biomass having bulk density range between 0.4 g/cm3 and 0.6 g/cm3 and that of the calorific values range between 3000 Cal/g and 4500 Cal/g. and said densified composition illustrated in figure 2.
In accordance to second embodiment, the present invention provides a process for preparing the densified biomass based packaging composition comprising the steps of:
(a) Pulverisation of dried biomass to form a size reduction of biomass, wherein size reduction of biomass is preferably between 2 to 20 mm.,
(b) Separately preparing a deep eutectic solvent at temperature between 35 to 60 °C and atmospheric pressure,
(c) Addition of step b) solvent to step a) biomass and increasing the temperature between 30 to 110 °C under constant stirring for time between 0.1 Hr to 10 Hr at atmospheric pressure,
(d) Addition of antisolvent at temperature between 30 to 110 °C under constant stirring for time between 0.1 Hr to 10 Hr at atmospheric pressure,
(e) Reducing the temperature to room temperature range between 20 to 35 °C,
(f) Filtration of step e) mass to separate a solvent using filter paper to obtain a wet densified biomass,
(g) Pouring the filtered biomass into a mould and drying under hot air oven at temperature between 60 to 110 °C to obtain a densified biomass based packaging composition,
(h) Tuning the porosity of the biomass based packaging composition using thermal treatment in a furnace under nitrogen at temperature between 200 to 600 °C.

In accordance to present invention, the deep eutectic solvent selected from the combination of Choline chloride -oxalic acid, Choline chloride- Urea, Zinc chloride- Urea, Choline chloride- ethylene glycol and more preferably a Choline chloride and oxalic acid in combination of weight ratio for Choline chloride and oxalic acid is between 0.1 to 10, more preferably 1:1.
In accordance to present invention, the antisolvent are selected from group of polar and protic solvents, wherein antisolvents are selected from water, ethanol, isopropyl alcohol, methanol and mixture thereof.
Further, the weight ratio of biomass to deep eutectic solvent is between 0.1 to 10, more preferably in weight proportion between 1:1 to 1:3.
In accordance with present invention, the deep eutectic solvent consisting of hydrogen bond donor and hydrogen bond acceptor is mixed with biomass sample. The lignin is separated from cellulose by preferential intermolecular hydrogen bonding with the deep eutectic solvent in the reactor. The antisolvent is then added to the mixture which solubilizes the deep eutectic solvent selectively. The lignin then rebinds with cellulose thereby altering the original hydrogen bonding between cellulose and lignin which gives unique morphology to biomass.

SCHEME I: Illustrates the flow diagram scientific phenomenon of producing a densified biomass material.

The foregoing description of the invention has been set merely to illustrate the current stage of invention and is not intended to be limiting. Since further development on detection techniques such as to record the reading in digital form/ image form or introducing/collaborating the available techniques for minimizing the scope of errors or maximizing the detection and sensitivity of the disclosed embodiments is possible. Therefore, such modification will towards incorporating the spirit and substance of the invention may occur to person skilled in the art, the invention should be construed to include everything within the scope of the disclosure.
The present invention is further illustrated in connection with particular examples as follows.

Example 1:Biomass collection : This technology uses the remains of agricultural process. The sample was collected from different part of Odisha, Maharashtra and many more parts of India. The rice stalk from Odisha was as useful as the horticultural remains of Maharashtra. The biomass was collected directly from the farm without any special treatment. The process is quite good for the dry biomasses. So, the cost of the raw material is very much less as compare to the high value product.

Example 2: Reduction of the biomass: The densification needs high extend of interaction between the microparticles of biomass and the chemical solvent. It needs size reduction by the virtue of grinding of the above pictured biomasses. We have used the pulveriser which is at our lab for this very crucial step. The extend of size reduction is also optimized at our lab after doing the experiment on regular basis.

Example 3: Solvent preparation: The solvent is Deep eutectic solvent. This solvent is responsible for the fractionation of the biomass by keeping the individual properties of the biomass unchanged. Mixture of Choline chloride and oxalic acid were taken in a specific proportion.
The DES which is being used is zero toxic and environmentally friendly. The solvent can be easily identified as the green chemical.

Example 4: Treatment of Biomass: The Deep eutectic solvent was taken in beaker and kept under stirring using overhead stirrer at a certain RPM. The temperature of solvent was maintained between 50-60 degree Celsius for optimized time at atmospheric pressure.

The prepared solvent is added in the size reduced biomass of example 2 of various type, size, and proportion. Now a mixture of biomass and solvent (DES) formed. The temperature was increased up to 90-110 degree Celsius at atmospheric pressure.

Stirring continues for 2 – 3 hours for effective mixing with the use of overhead stirrer. During this step temperature plays a very important role so the temperature at every 15 to 20 minutes is observed and adjusted in required situation.

After this, the antisolvent was added. A specific ratio of the antisolvent was added to the biomass reaction mixture for the complete recovery of the solvent (DES).
Temperature remains kept constant i.e., 90-110 degree Celsius and stirring continued for around 2-3 hours using the overhead stirrer. This step is also performed under the atmospheric pressure.

After addition of the antisolvent the temperature of the total mixture is higher than the room temperature. This mixture placed in a coolant for the reduction of the mixture temperature. This helps in the further filtration process as a handling perspective as well as this increases the rate of filtration.

After cooling the mixture allows for the sedimentation purpose as top phase contains the DES and the antisolvent and bottom phase contains the biomass fraction which later used for the densification purpose.

The top phase was isolated by doing decantation. The bottom phase was rich in the biomass fraction but it has some fraction of combination of solvent and antisolvent.
So, to isolate the remained liquid in the bottom part filtration process was adopted.

After the filtration process the fractionated biomass got collected which was sticky in nature containing fine particles which can be mould into any required shape. The solid remaining after filtration can be mould into any shape as per the application. The shape is not-limiting to hollow, solid, flat or perforated.
The above moulded shapes were taken to a dryer for removing the liquid fraction at temperature 85-110 degree Celsius as a result to obtained the densified biomass block of different shape and sizes. These blocks are of high compressive strength.
Non limiting step after drying is furnace drying wherein the densified material was exposed to a furnace temperature between 200 to 600 degree Celsius to provide a porosity to the densified material. The said porosity can be achieved by freeze drying process technique.

Example 5: Recovery of the solvent: The solvent got recovered by the application of decreasing the temperature of the remained liquid which got collected during the filtration process. In this step the residue liquid mixture that contains solvent, antisolvent and some fraction of the biomass is taken to a temperature range of 10 to 25 degree Celsius. By doing this the solvent got isolated in the form of crystal which can be reused again.

Example 6: A process for preparing the densified biomass based packaging composition From rice stalks:
(a) Raw dried rice stalks was pulverised to form a size reduction to about 10 to 15 mm,
(b) Separately preparing a deep eutectic solvent by mixing Choline chloride and oxalic acid under constant stirring at temperature between 35 to 60 °C and atmospheric pressure,
(c) Addition of step b) solvent to step a) biomass and increasing the temperature between 90 to 110 °C under constant stirring for time between 2 Hr to 3 Hr at atmospheric pressure,
(d) Addition of antisolvent at temperature between 90 to 110 °C under constant stirring for time between 2 Hr to 3 Hr at atmospheric pressure,
(e) Reducing the temperature to room temperature range between 20 to 35 °C,
(f) Filtration of step e) mass to separate a solvent using filter paper to obtain a wet densified biomass,
(g) Pouring the filtered biomass into a mould and drying under hot air oven at temperature between 85 to 110 °C to obtain a densified biomass based packaging composition.
(h) Tuning the porosity of the biomass based packaging composition using thermal treatment in a furnace under nitrogen at temperature between 400 to 600 °C.

Example 7: A process for preparing the densified biomass based packaging composition From dry garden waste:
(a) Raw dried garden waste was pulverised to form a size reduction to about 10 to 20 mm,
(b) Separately preparing a deep eutectic solvent by mixing Choline chloride and oxalic acid under constant stirring at temperature between 35 to 60 °C and atmospheric pressure,
(c) Addition of step b) solvent to step a) biomass and increasing the temperature between 90 to 110 °C under constant stirring for time between 2 Hr to 3 Hr at atmospheric pressure,
(d) Addition of antisolvent at temperature between 90 to 110 °C under constant stirring for time between 2 Hr to 3 Hr at atmospheric pressure,
(e) Reducing the temperature to room temperature range between 20 to 35 °C,
(f) Filtration of step e) mass to separate a solvent using filter paper to obtain a wet densified biomass,
(g) Pouring the filtered biomass into a mould and drying under hot air oven at temperature between 85 to 110 °C to obtain a densified biomass based packaging composition.
(h) Tuning the porosity of the biomass based packaging composition using thermal treatment in a furnace under nitrogen at temperature between 400 to 600 °C.
Example 8:Analysis of Densified material composition
A) Compression Testing
Step1: Measurement of dimensions of the specimen is done according to the machine. Here we choose circular discs and calculated the area of cross-section by applying the formula of pr2. The Radius of the sample was considered by taking average value with the help of digital Vernier Calliper.
Step:2: Once the sample is measured, the machine is calibrated. In our case, it was pre-calibrated. In case of not calibrated, it can be done by placing the measuring meter between the upper and lower slit of machine and the upper plate should touch the measuring meter. Then hydraulic pressure is to be applied by tightening the hydraulic valve and then pressure is applied though the hydraulic handle. If the pressure exerted in the measuring instrument and pressure gauge present in CTM shows the same value, it is well calibrated.
Step:3: After calibration, the sample is placed in between the slits by touching rotating knob to the sample gently. It need to be ensured that the sample is in the centre of the slits. After placing it , the hydraulic knob is rotated clock wise until it gets tighten. After ensuring it is tight, pressure is exerted by the handle which will be reflected in the pressure gauge.
Step:4: A sample of 3 identical dimensions should be taken and point to be noted that a deviation of result more then 15% should be discarded. Once we get the data of 3 samples, average load is calculated.
Average load= sum of values recorded in KN/total no of tests run
Step:5: Now compressive strength is calculated on the basis of below formula
Compressive strength= average load/area of cross-section of the sample

After calculation, one get the value in KN/cm2 , which is further converted into MPa.
1kN/cm2 = 1000N/cm2
1N/cm2 = 0.01 MPa

As can be seen from the compression strength graph of figure no. 6, the blocks made from rice stalk and 50% (w/w) mixture made from rice stalk and garden waste block have compression strength of greater than 10 MPa. This is considerably higher strength compared to extended polystyrene.

B) SEM image determination:
Equipment – FESEM
Brand – JEOL, JSM-7610 F Plus
EDX – JEOL
Operating Voltage – 5 kV
Magnification range – 500 – 2000

i) Sample Preparation: Samples were synthesized in the laboratory and were dried in a lab air oven at 105?C for two days before analysis. Small portion of the sample was taken using a doctor’s blade. This potion of samples ranged from 3 – 5 millimeters. They were carried in air-tight zip lock covers.
ii) Sample Mounting: Small portions of block samples were taken, for powder samples, a pinch of it was taken. Carbon tape was cut and pasted on the butt holders where sample was to be mounted. Sample was placed on the holders using a pair of tongs. Since sample was non – conducting, gold coating was done over it.
iii) Sputter Coating: Sputter coater was purged with nitrogen gas to maintain an inert atmosphere under the coater. Time was set to 90 seconds and a vaccum of ˜ 3 – 5 Pa was maintained. Gold coating for 90 seconds was done.
iv) Specimen Chamber: After the Gold coating was done, the sample holder was placed in the specimen chamber (at atmospheric pressure). After placing the holder, the Specimen chamber was then subjected to vaccum so that both the chambers come at a common pressure. After this, Sample was taken under an electron gun chamber for further analysis.
v) Analysis: Voltage is set to 5kV. Current is automatically set. The probe current was set at 6 mA by default. Sample is taken to the internal chamber when the pressure in both chambers becomes equal to 10-4 Pa.
Offset or thickness of the sample is entered, in this case, 5 mm was given. Sample was then adjusted below the electron gun by adjusting the working distance, with the SEM KEYBOARD. Magnification and working distance were kept variable depending on the morphology of sample.

SEM Results:
Figure 3: Shows SEM image of rice stalk (a) and block made from rice stalk (b). It can be seen from the image the rupture of lignin from intermediate cellulose chains in rice stalk blocks (b) compared to untreated rice stalk sample (a) along with the change in morphology in Figure 3.
Figure 4: Shows a SEM image of garden waste (a) and block made from garden waste (b). It can be seen from the image the rupture of lignin from intermediate cellulose chains in garden waste blocks (b) compared to untreated garden waste sample (a) along with the change in morphology in Figure 4.
Figure 5: shows the SEM image of block made from a 50% (w/w) mixture of rice stalk and garden waste which shows the characteristics of both rice stalk and garden waste block in terms of the morphology.

C) Density Analysis: Density analysis of various biomass blocks in various chemical treatments and various conditions
The general method of analysis: A standardized hollow aluminum cylinder was taken and measurements including length and diameter were calculated by using a digital vernier caliper. Inner radius and outer radius were measured and the volume of the inner part of the cylinder was calculated by using the formula V= pr2l .Then biomass was filled in the cylinder, weighed, and taken to various drying conditions.

Samples taken:
1. Raw rice stalks (RS)
2. Rice stalk powder after size reduction
3. Raw garden waste (GW)
4. Garden waste powders after size reduction
5. Raw Rice stalks + Raw Garden waste
6. Powder rice stalks + Powder Garden waste
7. RS residue after filtration
8. GW residue after filtration
9. RS + GW After filtration
10. RS block after drying
11. GW block after drying
12. RS + GW block After drying
13. RS after tube furnace
14. GW After tube furnace
15. RS+ GW After the furnace
16. RS After freeze drying
17. GW After freeze drying
18. RS + GW After freeze drying
19. RS + GW+ PAN After filtration
20. RS + GW+ PAN After drying
21. RS + GW+ PAN After furnace
22. RS + GW+ PAN After freeze drying

Sample Density (g/cm3)
Raw Powder After filtration After drying After furnace After freeze-drying
RS 0.159 0.381 1.204 1.516 0.417 0.301
GW 0.242 0.453 1.237 1.610 0.450 0.305
RS+GW 0.194 0.424 1.167 1.419 0.586
(200 °C, 30 Min) 0.285
RS+GW+PAN 0.200 0.402 1.124 1.211 0.484 0.311
Table no. 1

Sample GCV (Cal/g) GCV (Cal/cm3)
Raw biomass (typical) 3500 700
Rice stalk biomass block 3509 5319.6
Garden waste biomass block 4047 6515.7
Rice stalk + Garden waste
(1:1) mixture biomass block 3949 5603.6
Table no. 2: Gross Calorific Value data

Example 9:Effect of Process Parameter on densified Packaging materials:
A. Effect of weight ratio of Choline chloride and oxalic acid: As per the research, the weight ratio of CC/OA is optimised to 1:1 where the clear and transparent DES forms. This results the formation of highly densified biomass with a compressibility strength ranges from2.95MPa to 10.79MPa and density ranges from 1.00 to 1.79g/cm3
B. Effect of different deep eutectic solvents on process: Different combination of DES was used for example Choline chloride- Urea, ZnCl2- Urea, Choline chloride- ethylene glycol in ratio of 1:1 with biomass. However the density and compressive strength was between 0.517 to 0.723g/cm3 and 4.9 to 8.7 MPa accordingly.
C. Effect of weight ratio of biomass and eutectic solvent: Higher the amount of DES ( Choline chloride+ oxalic acid), higher is the density of the material formed from it. This is due to higher the concentration of DES results higher fractionation of biomass and hence more fraction of lignin extracts out with the anti solvent by attaching with it.
D. Effect of antisolvent: Ratio of Reaction mass to antisolvent is between 1:1 to 1:10, and more preferably 1:3.

i) Density of material is highest when only water is used.
ii) Density of material is lowest when only ethanol is used
iii) Density of material is moderate when mixture of ethanol and water is used.
E. Reusability of recycled solvents: The solvent which was recycled in example 5 has taken for further biomass preparation. After preparing we found the result varies slightly after 7th recycling of solvent. However the density varies slightly between 1.00 to 1.8gm/cm3. After 7th recycling the density was 0.783gm/cm3.

The advantages of present invention are:
• It provides a modified process to densify biomass wherein, the density of biomass can be increased from 3 to 100 times the original density.
• It provides a modified process to densify biomass wherein, the chemical reagents used are completely recycled.
• It provides a modified process to densify biomass wherein, drying the biomass feedstock before processing is not required.
• It provides a modified process to densify biomass wherein, environmentally friendly solvent is used for the processing of biomass.
• It provides a modified process to densify biomass wherein, the densification process occurs at atmospheric pressure.
• It provides a modified process to densify biomass wherein, the densification process occurs at temperature below 100 degree Celsius.
• It provides a modified process to manufacture packaging material that is biodegradable.
• It provides a modified process to manufacture packaging material that is made from biobased feedstock.
• It provides a modified process to manufacture biobased packaging material that cannot be attacked by rodents.
• It provides a modified process to manufacture eco-friendly packaging material that can utilize agricultural waste.
• It provides a modified process to manufacture eco-friendly packaging material that can utilize biomass generated from any source.
• It provides a modified process to manufacture packaging material that is stronger and more rigid than polystyrene.
• It provides a modified process to manufacture packaging material that is stronger and more rigid than polyurethane.

The invention described herein are provided for the purpose of understanding the invention and not for limiting the scope of the invention.
,CLAIMS:We claim,
1. A densified biomass based packaging composition, consisting of: densified biomass having bulk density range between 0.4 g/cm3 and 0.6 g/cm3 and that of the calorific values range between 3000 Cal/g and 4500 Cal/g.
2. The densified biomass based packaging composition as claimed in claim 1, wherein the biomass is selected from lignin base Raw rice stalks, Raw garden waste, wood and mixture thereof.
3. A process for preparing the densified biomass based packaging composition comprising the steps of:
Step a): Pulverisation of dried biomass to form a size reduction of biomass,
Step b): Separately preparing a deep eutectic solvent at temperature between 35 to 60 °C and atmospheric pressure,
Step c): Addition of step b) solvent to step a) biomass and increasing the temperature between 30 to 110 °C under constant stirring for time between 0.1 Hr to 10 Hr at atmospheric pressure,
Step d): Addition of antisolvent at temperature between 30 to 110 °C under constant stirring for time between 0.1 Hr to 10 Hr at atmospheric pressure,
Step e): Reducing the temperature to room temperature range between 20 to 35 °C,
Step f): Filtration of step e) mass to separate a solvent using filter paper to obtain a wet densified biomass,
Step g): Pouring the filtered biomass into a mould and drying under hot air oven at temperature between 60 to 110 °C to obtain a densified biomass based packaging composition,
Step h): Tuning the porosity of the biomass based packaging composition using thermal treatment in a furnace under nitrogen at temperature between 200 to 600 °C.

4. The process for preparing the densified biomass based packaging composition as claimed in claim 3, wherein size reduction of biomass is between 2 to 20 mm.
5. The process for preparing the densified biomass based packaging composition as claimed in claim 3, wherein the deep eutectic solvent selected from the combination of Choline chloride -oxalic acid, Choline chloride- Urea, Zinc chloride- Urea, Choline chloride- ethylene glycol.
6. The process for preparing the densified biomass based packaging composition as claimed in claim 5, wherein weight ratio of Choline chloride and oxalic acid is between 0.1 to 10.
7. The process for preparing the densified biomass based packaging composition as claimed in claim 3, wherein the antisolvent are selected from group of polar and protic solvents.
8. The process for preparing the densified biomass based packaging composition as claimed in claim 7, wherein antisolvents are selected from water, ethanol, isopropyl alcohol, methanol and mixture thereof.
9. The process for preparing the densified biomass based packaging composition as claimed in claim 3, wherein weight ratio of biomass to deep eutectic solvent is between 0.1 to 10.
10. The process for preparing the densified biomass based packaging composition as claimed in claim 3, wherein time for step c) and step d) is selected between 0.1 Hr to 3 Hr .