A method for synthesizing furfural and ethanol by combination of biochemical processes

Abstract

This invention discloses a method for the synthesis of furfural and ethanol from green coconut (Cocos nucifera L.) husk. The method involves chemical reaction for furfural production and a biological fermentation for ethanol synthesis. In the chemical step, the green coconut husk undergoes acid hydrolysis in a high-pressure reactor, yielding furfural. The residual waste from this step is then utilized as a substrate for fermentation by Saccharomyces cerevisiae, producing ethanol. The integrated approach efficiently converts the cellulosic and hemicellulosic components of the green coconut husk into two industrially valuable compounds, furfural and ethanol, from a single agricultural waste stream. The invention provides a cost-effective and environmentally sustainable method for resource utilization and waste reduction.

Description

[0001] A METHOD FOR SYNTHESIZING FURFURAL AND ETHANOL BY COMBINATION OF BIOCHEMICAL PROCESSES

[0002] FIELD OF THE INVENTION

[0003] The present disclosure relates to the synthesis of value added compounds, specifically to a method for synthesizing furfural and ethanol by combination of biochemical processed.

[0004] BACKGROUND OF THE INVENTION

[0005] The production of value-added compounds such as ethanol and furfural has gained significant importance due to their wide range of industrial applications. Ethanol, a versatile organic solvent, finds extensive use in chemical, petrochemical, and pharmaceutical industries, as well as in the production of sanitizers, antiseptics, cosmetics, and biofuels. Furfural, on the other hand, is an important intermediate in the synthesis of various chemicals and resins.

[0006] Traditionally, ethanol has been produced through the fermentation of fruit juices, such as sugarcane and grape juice, involving complex and simple sugars. However, the use of simple sugars for fermentation is not economically feasible due to their high market value. Agricultural waste, rich in carbohydrates like cellulose and hemicellulose, has emerged as a promising alternative feedstock for the production of ethanol and furfural.

[0007] While various agricultural residues, including sugarcane bagasse, wheat and rice mill byproducts, fruit peels, and com husks, have been explored for ethanol production, the conversion of these lignocellulosic materials into fermentable sugars remains a significant challenge. The pretreatment steps required to break down the cellulose and hemicellulose into simple sugar moieties are often complex and costly.

[0008] Similarly, the production of furfural from agricultural waste necessitates the efficient conversion of hemicellulose components through acid hydrolysis. While several feedstocks, such as com cobs, sugarcane bagasse, sorghum husk, rice straw, and fruit leaves, have been investigated, the development of cost-effective and efficient production methods remains a critical challenge.

[0009] Furthermore, the existing technologies for the production of ethanol and furfural often operate independently, leading to inefficient utilization of the feedstock and generating significant waste streams. There is a need for an integrated approach that can simultaneously produce both value-added compounds from a single agricultural waste stream, thereby improving resource efficiency and reducing environmental impact.

[0010] This invention relates to a method that addresses these challenges by utilizing green coconut (Cocos nucifera L.) husk, a readily available agricultural waste, as a feedstock for the simultaneous production of furfural and ethanol. The green coconut husk, containing significant amounts of cellulose, hemicellulose, and lignin, presents an attractive opportunity for the synthesis of these valuable compounds through an integrated process.

[0011] SUMMARY OF THE INVENTION

[0012] The present disclosure relates to a method for synthesizing furfural and ethanol by combination of biochemical processed. The present invention discloses a method for the synthesis of two value-added compounds, furfural and ethanol, from a single agricultural waste stream, specifically the green coconut (Cocos nucifera L.) husk. The chopped green coconut husk is subjected to acid hydrolysis using sulfuric acid. The reaction is carried out in a high-pressure stainless-steel jacketed reactor, where the mixture is heated in two phases. The first phase involves heating the reaction mixture at a temperature range of 115-125°C and a pressure of 1-2 kg / cm2for 70 minutes, followed by further heating at a temperature range of 158-168°C and a pressure of 5-6 kg / cm2for 30 minutes. The crude reaction product containing furfural is collected through condensation.In the second phase, the collected crude reaction product is subjected to batch distillation at 100°C for 2-3 hours to obtain the final furfural product. The residual dry sludge from the chemical reaction is hydrated and used as a substrate for the biological fermentation process to produce ethanol. The sludge is neutralized by the addition of an alkali, and the supernatant is used as the fermentation medium. The yeast Saccharomyces cerevisiae is employed as the fermentation microorganism, and the fermentation is carried out under anaerobic conditions in a shake flask culture. The invention provides an integrated approach for the efficient utilization of green coconut husk, a readily available agricultural waste, by converting its cellulosic and hemicellulosic components into two industrially valuable compounds, furfural and ethanol.

[0013] The present disclosure seeks to provide a method for synthesizing furfural and ethanol by combination of biochemical processed. The method comprises: collecting green coconut husk and chopping the green coconut husk using a grinder to form a wet fine biomass;press-filtering the wet fine biomass to remove excess and flowing water;treating 290-310 grams of the chopped green coconut, preferably 300 grams in 160-180 milliliters sulfuric acid, preferably 170ml to form a mixture; adjusting the solid / liquid ratio of the mixture to 0.55 by allowing it to stand at room temperature for 20 minutes and thoroughly mixing to create a homogenous slurry ;loading the slurry into a high-pressure stainless-steel jacketed reactor and heating the slurry in two phases for obtaining furfural;isolating Saccharomyces cerevisiae yeast from baker's yeast granules;separating dry sludge from the reactor and hydrating the dry sludge by adding distilled water and keeping it overnight, wherein after hydration, supernatant is decanted;neutralizing an acidic pH of the sludge supernatant by adding 1-2 grams NaOH pellets, preferably 1.1 gm with constant stirring;preparing inoculum in YPD medium, wherein inoculation of a sterilized medium with Saccharomyces cerevisiaecu we. from slant, followed by incubation on a gyratory incubator shaker at 300 rpm, 32 ± 2°C for 20 hours;preparing a fermentation medium with neutralized sludge supernatant, and adjusting a pH to 4.0 in a shake flask culture; andadding 10% inoculum in 30 ml sterile medium and maintaining anaerobic conditions using polythene-coated cotton plugs on flasks for fermentation to obtain ethanol, wherein aseptically drawing samples of the medium at regular intervals of 24 hours.

[0014] In an embodiment, in a first phase, heating the slurry in the reactor over a temperature range of 115-125°C at 1-2 kg / cm2pressure for 70 minutes, followed by further heating the reactor for over 30 minutes to achieve a temperature range of 158-168°C at 5-6 kg / cm2pressure and collecting crude reaction product through a condenser until the reactor temperature reduces to 122°C, then repeating the process at 165°C to collect additional crude reaction product.

[0015] In an embodiment, in a second phase, subjecting the collected crude reaction product to batch distillation at 100°C for 2-3 hours into round bottom flask kept on oil bath to obtain furfural content in the residue.

[0016] In an embodiment, a pure strain of the yeast is maintained on YPD agar at 4°C.

[0017] In an embodiment, the YPD medium containing 10 g / 1 yeast extract, 20 g / 1 peptone, and 20 g / 1 dextrose, with pH adjusted to 7.0.

[0018] In an embodiment, the concentration of furfural synthesized was found to be 63% and remaining waste of acid hydrolysis is separated from reactor on cooling, out of that, lOOgm of waste is added into 200ml of distilled water and soaked it for overnight thereby 130 ml of supernatant of pH 1.0 is separated, wherein 1. Igm of NaOH is consumed to neutralize the supernatant at the pH 7.0.

[0019] In an embodiment, the acid hydrolysis resulted in breakdown of complex sugar moieties into simple moieties, which is converted into furfural, from which some simple sugars remain unconverted, wherein by using DNSA method, the reducing sugar present in supernatant is found to be lOmg / ml (10%).

[0020] In an embodiment, a high concentration of reducing sugar is present in chemical reaction waste, which is converted into ethanol by yeast fermentation, wherein the 28% ethanol is obtained, wherein pH of fermentation sample is constant at 4.0 up to 96 hours, whereas an initial pH of broth is 6.0, wherein an Alcoholic fermentation is accomplished efficiently at pH below 5.0, wherein Growth of yeast produced acidic end products in fermentation that accumulate in the extracellular medium, wherein the medium's pH is lowered due to the yeast's substantial synthesis of organic acids.

[0021] An objective of the present disclosure is to provide a method for synthesizing furfural and ethanol by combination of biochemical processed.

[0022] Another object of the present disclosure is to a method for the simultaneous synthesis of furfural and ethanol from a single agricultural waste stream, specifically the green coconut (Cocos nucifera L.) husk.

[0023] Another objective of the present disclosure is to utilize the cellulosic and hemicellulosic components of the green coconut husk for the production of value-added compounds through an integrated approach.

[0024] Another objective of the present disclosure is to develop an efficient chemical process for the synthesis of furfural from green coconut husk through acid hydrolysis.

[0025] Another objective of the present disclosure is to utilize the residual waste from the furfural synthesis process as a substrate for the biological production of ethanol through fermentation.

[0026] Another objective of the present disclosure is to employ the yeast Saccharomyces cerevisiae as the fermentation microorganism for the conversion of the residual waste into ethanol. Another objective of the present disclosure is to provide a cost-effective and environmentally sustainable method for the production of two valuable compounds, furfural and ethanol, from a readily available agricultural waste stream.

[0027] Yet, another objective of the present disclosure is to improve resource efficiency and reduce waste generation by utilizing the green coconut husk as a feedstock for the simultaneous production of furfural and ethanol.

[0028] To further clarify advantages and features of the present disclosure, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

[0029] BRIEF DESCRIPTION OF FIGURES

[0030] These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

[0031] Figure 1 illustrates a flow chart of a method for synthesizing furfural and ethanol by combination of biochemical processes in accordance with an embodiment of the present disclosure;

[0032] Figure 2 illustrates diagrams of chemical structure of furfural and ethanol in accordance with an embodiment of the present disclosure;

[0033] Figure 3 illustrates a diagram depicting the synthesis of furfural and ethanol by combination of biochemical processes in accordance with an embodiment of the present disclosure;

[0034] Figure 4 illustrate Green coconut husk chopped to fine fibers in accordance with an embodiment of the present disclosure;

[0035] Figure 5 illustratesBrown furfural oil as end product, and Remaining waste after acid hydrolysis in accordance with an embodiment of the present disclosure; Figures 6A and 6B illustrate graphs representing Gas Chromatogram of standard Furfural in accordance with an embodiment of the present disclosure; and

[0036] Figure 7A and 7B illustrates graphs representing Gas Chromatogram of standard sample of ethanol in accordance with an embodiment of the present disclosure.

[0037] Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have been necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present disclosure. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

[0038] DETAILED DESCRIPTION:

[0039] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

[0040] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not intended to be restrictive thereof.

[0041] Reference throughout this specification to “an aspect”, “another aspect” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, appearances of the phrase “in an embodiment”, “in another embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or sub-systems or elements or structures or components proceeded by "comprises...a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.

[0043] Embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings.

[0044] The present invention aims to provide a composition for synthesizing furfural and ethanol by combination of biochemical processes, the composition comprises:a power extract of green coconut husk, from 290-310 grams;an aqueous extract of Sulfuric acid, from 160-180 milliliters;a power extract of NaOH pellets, from 1-2 grams; anda power extract of a YPD medium components, from 40-60 grams / liter.

[0045] In an embodiment the weight amount of the green coconut husk, Sulfuric acid, NaOH pellets, and YPD medium, is, 300gm, 170ml, l.lgm, and 50g / l, respectively, wherein the YPD medium containing 10 g / 1 yeast extract, 20 g / 1 peptone, and 20 g / 1 dextrose.

[0046] Figure 1 illustrates a flow chart of a method for synthesizing furfural and ethanol by combination of biochemical processes in accordance with an embodiment of the present disclosure.

[0047] Referring to Figure 1, the method (100) includes pluralities of steps for synthesizing furfural and ethanol by combination of biochemical processes, the steps are described below,

[0048] At step (102), the method (100) includes collecting green coconut husk and chopping the green coconut husk using a grinder to form a wet fine biomass. At step (104), the method (100) includes press-filtering the wet fine biomass to remove excess and flowing water.

[0049] At step (106), the method (100) includes treating 290-310 grams of the chopped green coconut, preferably 300 grams in 160-180 milliliters sulfuric acid, preferably 170ml to form a mixture.

[0050] At step (108), the method (100) includes adjusting the solid / liquid ratio of the mixture to 0.55 by allowing it to stand at room temperature for 20 minutes and thoroughly mixing to create a homogenous slurry.

[0051] At step (110), the method (100) includes loading the slurry into a high-pressure stainless-steel jacketed reactor and heating the slurry in two phases for obtaining furfural.

[0052] At step (112), the method (100) includes isolating Saccharomyces cerevisiae yeast from baker's yeast granules.

[0053] At step (114), the method (100) includes separating dry sludge from the reactor and hydrating the dry sludge by adding distilled water and keeping it overnight, wherein after hydration, supernatant is decanted.

[0054] At step (116), the method (100) includes neutralizing an acidic pH of the sludge supernatant by adding 1-2 grams NaOH pellets, preferably l.lgm with constant stirring.

[0055] At step (118), the method (100) includes preparing inoculum in YPD medium, wherein inoculation of a sterilized medium with Saccharomyces cerevisiae culture from slant, followed by incubation on a gyratory incubator shaker at 300 rpm, 32 ± 2°C for 20 hours.

[0056] At step (120), the method (100) includes preparing a fermentation medium with neutralized sludge supernatant, and adjusting a pH to 4.0 in a shake flask culture.

[0057] At step (122), the method (100) includes adding 10% inoculum in 30 ml sterile medium and maintaining anaerobic conditions using polythene-coated cotton plugs on flasks for fermentation to obtain ethanol, wherein aseptically drawing samples of the medium at regular intervals of 24 hours.

[0058] In an embodiment, in a first phase, heating the slurry in the reactor over a temperature range of 115-125°C at 1-2 kg / cm2pressure for 70 minutes, followed by further heating the reactor for over 30 minutes to achieve a temperature range of 158-168°C at 5-6 kg / cm2pressure and collecting crude reaction product through a condenser until the reactor temperature reduces to 122°C, then repeating the process at 165°C to collect additional crude reaction product.

[0059] In an embodiment, in a second phase, subjecting the collected crude reaction product to batch distillation at 100°C for 2-3 hours into round bottom flask kept on oil bath to obtain furfural content in the residue.

[0060] In an embodiment, a pure strain of the yeast is maintained on YPD agar at 4°C.

[0061] In an embodiment, the YPD medium containing 10 g / 1 yeast extract, 20 g / 1 peptone, and 20 g / 1 dextrose, with pH adjusted to 7.0.

[0062] In an embodiment, the concentration of furfural synthesized was found to be 63% and remaining waste of acid hydrolysis is separated from reactor on cooling, out of that, lOOgm of waste is added into 200ml of distilled water and soaked it for overnight thereby 130 ml of supernatant of pH 1.0 is separated, wherein 1. Igm of NaOH is consumed to neutralize the supernatant at the pH 7.0.

[0063] In an embodiment, the acid hydrolysis resulted in breakdown of complex sugar moieties into simple moieties, which is converted into furfural, from which some simple sugars remain unconverted, wherein by using DNSA method, the reducing sugar present in supernatant is found to be lOmg / ml (10%).

[0064] In an embodiment, a high concentration of reducing sugar is present in chemical reaction waste, which is converted into ethanol by yeast fermentation, wherein the 28% ethanol is obtained, wherein pH of fermentation sample is constant at 4.0 up to 96 hours, whereas an initial pH of broth is 6.0, wherein an Alcoholic fermentation is accomplished efficiently at pH below 5.0, wherein Growth of yeast produced acidic end products in fermentation that accumulate in the extracellular medium, wherein the medium's pH is lowered due to the yeast's substantial synthesis of organic acids

[0065] Figure 2 illustrates diagrams of chemical structure of furfural and ethanol in accordance with an embodiment of the present disclosure.

[0066] Furfural, also known as 2-furancarboxaldehyde or furfuryl aldehyde, is a valuable compound in industrial settings. It's a colorless, clear, oily liquid with a distinct odor similar to benzaldehyde. However, its color changes upon exposure to light and air, which is why it's stored in amber containers. Furfural is widely used as a solvent in lubricant manufacturing and petroleum processing. It also serves as an intermediate compound for various applications, including the production of furfuryl alcohol, tetrahydrofuran, and its use in pharmaceuticals, herbicides, and fragrances. Furfural is typically produced through the hydrolysis of cellulose and hemicellulose compounds in the presence of strong acids. This process generates residues of five and six-carbon sugars like pentoses and xyloses, which are then dehydrated to form furfural.

[0067] Ethyl alcohol, also known as ethanol, is a flammable, volatile, and colorless organic solvent that holds significant value in industries such as chemical, petrochemical, and pharmaceuticals. Due to its antiseptic and disinfectant properties, ethanol finds widespread use in sanitizers, antiseptics, ointments, cosmetics, and cleaning products for surfaces and floors. It's also incorporated into various medicinal formulations and serves as a biofuel. Ethanol is synthesized through different chemical reactions either as an intermediate or a byproduct. Naturally, it's produced through the fermentation of fruit juices like sugarcane and grape juice, where complex and simple sugars are converted into ethanol.

[0068] Figure 3 illustrates a diagram depicting the synthesis of furfural and ethanol by combination of biochemical processes in accordance with an embodiment of the present disclosure.

[0069] Referring to Figure 3, the synthesis of the furfural and ethanol is carried out by combination of multiple biochemical processes, wherein a detailed description of the synthesis is described below.

[0070] Figure 4 illustrate Green coconut husk chopped to fine fibers in accordance with an embodiment of the present disclosure;

[0071] Referring to Figure 4, Green coconut husks were gathered from a local market. They were then chopped using a grinder to obtain wet, finely chopped biomass. This biomass underwent pressfiltering to eliminate excess water and flowing water.

[0072] To synthesize furfural, 300 grams of chopped green coconut were soaked in 170 milliliters of IM sulfuric acid. After allowing the mixture to stand at room temperature for 20 minutes to achieve a solid / liquid ratio of 0.55, it was thoroughly mixed to form a homogenous slurry. This slurry was then transferred into a high-pressure stainless-steel jacketed reactor.

[0073] The synthesis process consists of two phases. In the first phase, the reaction mixture was heated within the temperature range of 115-125°C at a pressure of 1-2 kg / cm2for 70 minutes. Subsequently, the reactor was further heated for 30 minutes to reach a temperature range of 158- 168°C at a pressure of 5-6 kg / cm2The crude reaction product was collected through a condenser until the reactor temperature dropped to 122°C. The reactor temperature was then raised to 165°C, and the process was repeated to collect more crude reaction product.

[0074] In the second phase, the collected crude reaction product underwent batch distillation at 100°C for 2-3 hours in a round bottom flask placed on an oil bath. The residue obtained from this distillation was analyzed for its furfural content.

[0075] In an embodiment, a biochemical process for fermentation is as described below.

[0076] Microorganism:

[0077] Yeast, specifically Saccharomyces cerevisiae, was isolated from baker’s yeast granules and maintained as a pure strain on YPD agar at 4°C.

[0078] Substrate for ethanol production:

[0079] After completing the chemical reaction, dry sludge was separated from the reactor. This dry sludge was hydrated by adding distilled water and allowing it to soak overnight. Once hydrated, the supernatant (the liquid portion above the settled solids) was decanted and used as the substrate for fermentation.

[0080] Neutralization:

[0081] Since the pH of the sludge was acidic, it was neutralized by adding alkali. This was achieved by adding a known quantity of NaOH pellets with constant stirring to neutralize the supernatant.

[0082] Inoculum preparation:

[0083] An inoculum was prepared using YPD medium with the following concentrations per liter: yeast extract, 10g; peptone, 20g; dextrose, 20g; pH adjusted to 7.0. After sterilization in an autoclave, the inoculum was prepared by transferring a loopful culture of S. cerevisiae from a slant incubated on a gyratory incubator shaker (at 300 rpm and 32 ± 2°C) for 20 hours.

[0084] Fermentation: The fermentation experiments were conducted using shake flask culture. The fermentation medium was prepared with concentrations per liter: yeast extract, 10g; peptone, 20g; and dextrose was replaced by the neutralized sludge supernatant. The pH of the medium was adjusted to 4.0. Fermentation of sugar was initiated by adding 10% (w.r.t. medium) inoculum into 30 ml of sterile medium. To create anaerobic conditions, the flasks were sealed with polythene-coated cotton plugs. Samples of the medium were aseptically drawn after regular intervals of 24 hours for analysis.

[0085] In an embodiment, analytical methods include sugar estimation and furfural and ethanol estimation. The analytical methods are as described below.

[0086] Sugar Estimation:

[0087] The sugar content of the neutralized sludge supernatant was determined using the 3,5- dinitrosalicylic acid (DNSA) method as described by Sumner in 1921.

[0088] Furfural and Ethanol Estimation by GC:

[0089] The concentrations of furfural and ethanol in the liquid were analyzed using gas chromatography (GC) with a flame ionization detector (FID) and a DB-5 column. High-purity nitrogen was used as the carrier gas at a flow rate of 1.5 mL / min. The detector temperatures were set to 250°C for furfural and 100°C for ethanol.

[0090] For the separation of furfural, the column oven temperature was programmed to start at 100°C for 2 minutes and then ramped to 250°Cover 10 minutes. In contrast, for ethanol, an isothermal condition was maintained at 120°C throughout the analysis.

[0091] This invention focuses on utilizing acid hydrolysis to convert green coconut husk, which is a byproduct of the agricultural and oil industries, into furfural. The process involved using one molar of sulfuric acid for the acid hydrolysis of green coconut husk. This concentration of acid resulted in the formation of a high amount of pentosan residues, leading to a high yield of furfural.

[0092] Once the reactor temperature reached 160°C, it was held steady for 30 minutes. Subsequently, the distillation column valve was opened to initiate the distillation process. Distillation was stopped either when the temperature reached 120°C or when the pressure reached 2 kg / cm2This cycle was repeated twice to increase the yield of condensate. Figure 5 illustrates Brown furfural oil as end product, and Remaining waste after acid hydrolysis in accordance with an embodiment of the present disclosure.

[0093] In the end of the above said reaction, 250ml of condensate was collected. This condensate (crude) was subjected to another distillation process in round bottom flask kept on oil bath. Eventually, 30gm of brown color furfural oil was obtained in round bottom flask, as shown in Figure 5A.

[0094] Figures 6A and 6B illustrate graphs representing Gas Chromatogram of standard Furfural in accordance with an embodiment of the present disclosure.

[0095] Furfural was quantified in the final product using gas chromatography. The retention time (Rt) of the standard furfural (as shown in Figure6A) was 1.7 minutes, while the Rt of furfural in the sample was slightly altered due to the presence of other compounds (as depicted in Figure6B). The concentration of synthesized furfural was determined to be 63%. Additionally, some impurities were also detected alongside furfural in the final product.

[0096] The remaining waste of acid hydrolysis was separated from reactor on cooling (Figure5B). Out of that, lOOgm of waste was added into 200ml of distilled water and soaked it for overnight. After that, 130 ml of supernatant of pH 1.0 was separated. To neutralize the supernatant at the pH 7.0, 1.1 gm ofNaOH was consumed.

[0097] Acid hydrolysis resulted in breakdown of complex sugar moieties into simple moieties, which was converted into furfural. But all residues of simple sugars are not converted into furfural, some residues remain unconverted. By using DNS A method, the reducing sugar present in supernatant was found to be lOmg / ml (10%).

[0098] Due to the high concentration of reducing sugars present in the waste from the chemical reaction, it was feasible to convert these sugars into ethanol through yeast fermentation. The pH of the fermentation sample remained constant at 4.0 for 96 hours (as shownin Table 1 given below), although the initial pH of the broth was 6.0. Efficient alcoholic fermentation typically occurs at pH levels below 5.0. During fermentation, yeast growth generates acidic byproducts that accumulate in the surrounding medium, leading to a decrease in pH. In anaerobic fermentation conditions, cell growth is hindered due to the absence of oxygen, preventing biomass accumulation. The optimal pH range for yeast growth falls between 5.5 and 6.0, where the rate of multiplication increases nonlinearly with increasing pH. In thisinvention, the yeast biomass remained constant throughout the experiment (as shown in Table 1 given below).

[0099] Figure 7A and 7B illustrates graphs representing Gas Chromatogram of standard sample of ethanol in accordance with an embodiment of the present disclosure.

[0100] The ethanol yield was influenced by both sugar concentration and yeast activity. In the ongoing fermentation process, the ethanol concentration initially increased over time, reaching 28% after 72 hours. However, beyond this point, the ethanol yield began to decrease. Gas chromatography was used to estimate the ethanol content, and the retention time of the standard ethanol matched the chromatogram of the sample (as shown in Figure 7A and 7B).

[0101] The present invention utilized green coconut waste to produce furfural via acid hydrolysis at moderate temperatures. These specific reaction conditions were demonstrated to enhance furfural yield without compromising the integrity of the hydrolyzed sugar components. Typically, byproducts of chemical reactions are not suitable for biological processes due to their hazardous nature. However, in this case, the waste byproduct from the chemical reaction was efficiently repurposed for biological processes.

[0102] Pretreating agricultural waste is crucial to convert complex sugars into simpler sugar units. The waste generated from furfural production contains a high concentration of reducing sugars devoid of hazardous or toxic chemicals, making it directly applicable for bioethanol production. This invention stands out as it solely relies on a single agricultural waste source, the green coconut husk, to synthesize two different industrially important compounds. This approach marks the first instance of using green coconut husk as a substrate while employing both biological and chemical processes simultaneously to manufacture two value-added compounds.

[0103] The drawings and the forgoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, orders of processes described herein may be changed and are not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts necessarily need to be performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples. Numerous variations, whether explicitly given in the specification or not, such as differences in structure, dimension, and use of material, are possible. The scope of embodiments is at least as broad as given by the following claims.

[0104] Benefit s, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any component(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature or component of any or all the claims.

Claims

CLAIMS1. A composition for synthesizing furfural and ethanol by combination of biochemical processes, the composition comprises: a power extract of green coconut husk, from 290-310 grams; an aqueous extract of Sulfuric acid, from 160-180 milliliters; a power extract of NaOH pellets, from 1-2 grams; and a power extract of a YPD medium components, from 40-60 grams / liter.

2. The composition as claimed in claim 1, wherein the weight amount of the green coconut husk, Sulfuric acid, NaOH pellets, and YPD medium, is, 300gm, 170ml, l.lgm, and 50g / l, respectively, wherein the YPD medium containing 10 g / 1 yeast extract, 20 g / 1 peptone, and 20 g / 1 dextrose.

3. A method for synthesizing furfural and ethanol by combination of biochemical processes, the method comprises: collecting green coconut husk and chopping the green coconut husk using a grinder to form a wet fine biomass; press-filtering the wet fine biomass to remove excess and flowing water; treating 290-310 grams of the chopped green coconut, preferably 300 grams in 160-180 milliliters sulfuric acid, preferably 170ml to form a mixture; adjusting the solid / liquid ratio of the mixture to 0.55 by allowing it to stand at room temperature for 20 minutes and thoroughly mixing to create a homogenous slurry; loading the slurry into a high-pressure stainless-steel jacketed reactor and heating the slurry in two phases for obtaining furfural; isolating Saccharomyces cerevisiae yeast from baker's yeast granules; separating dry sludge from the reactor and hydrating the dry sludge by adding distilled water and keeping it overnight, wherein after hydration, supernatant is decanted; neutralizing an acidic pH of the sludge supernatant by adding 1-2 grams NaOH pellets, preferably 1. Igm with constant stirring;preparing inoculum in YPD medium, wherein inoculation of a sterilized medium with Saccharomyces cerevisiaecAXwe from slant, followed by incubation on a gyratory incubator shaker at 300 rpm, 32 ± 2°C for 20 hours; preparing a fermentation medium with neutralized sludge supernatant, and adjusting a pH to 4.0 in a shake flask culture; and adding 10% inoculum in 30 ml sterile medium and maintaining anaerobic conditions using polythene-coated cotton plugs on flasks for fermentation to obtain ethanol, wherein aseptically drawing samples of the medium at regular intervals of 24 hours.

4. The method as claimed in claim 3, wherein in a first phase, heating the slurry in the reactor over a temperature range of 115-125°C at 1-2 kg / cm2pressure for 70 minutes, followed by further heating the reactor for over 30 minutes to achieve a temperature range of 158-168°C at 5-6 kg / cm2pressure and collecting crude reaction product through a condenser until the reactor temperature reduces to 122°C, then repeating the process at 165°C to collect additional crude reaction product.

5. The method as claimed in claim 3, wherein in a second phase, subjecting the collected crude reaction product to batch distillation at 100°C for 2-3 hours into round bottom flask kept on oil bath to obtain furfural content in the residue.

6. The method as claimed in claim 3, wherein a pure strain of the yeast is maintained on YPD agar at 4°C.

7. The method as claimed in claim 3, wherein the YPD medium containing 10 g / 1 yeast extract, 20 g / 1 peptone, and 20 g / 1 dextrose, with pH adjusted to 7.0.

8. The method as claimed in claim 3, wherein the concentration of furfural synthesized was found to be 63% and remaining waste of acid hydrolysis is separated from reactor on cooling, out of that, lOOgm of waste is added into 200ml of distilled water and soaked it for overnight thereby 130 ml of supernatant of pH 1.0 is separated, wherein l.lgm of NaOH is consumed to neutralize the supernatant at the pH 7.0.

9. The method as claimed in claim 8, wherein the acid hydrolysis resulted in breakdown of complex sugar moieties into simple moieties, which is converted into furfural, from which somesimple sugars remain unconverted, wherein by using DNSA method, the reducing sugar present in supernatant is found to be lOmg / ml (10%).

10. The method as claimed in claim 8, wherein a high concentration of reducing sugar is present in chemical reaction waste, which is converted into ethanol by yeast fermentation, wherein the 28% ethanol is obtained, wherein pH of fermentation sample is constant at 4.0 up to 96 hours, whereas an initial pH of broth is 6.0, wherein an Alcoholic fermentation is accomplished efficiently at pH below 5.0, wherein Growth of yeast produced acidic end products in fermentation that accumulate in the extracellular medium, wherein the medium's pH is lowered due to the yeast's substantial synthesis of organic acids

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