Bioconversion of waste generated during ethanol production into value-added products for sustainable utilization of rice straw

Abstract The implementation of biorefinery concepts into existing pulp and paper mills is a key step for a sustainable utilization of the natural resource wood. Water prehydrolysis of wood is an interesting process for the recovery of xylo-oligosaccharides and derivatives thereof, while at the same time cellulose is preserved to a large extent for subsequent dissolving pulp production. The recovery of value-added products out of autohydrolyzates is frequently hindered by extensive lignin precipitation, especially at high temperatures. In this study, a new high-temperature adsorption process (HiTAC process) was developed, where lignin is removed directly after the autohydrolysis, which enables further processing of the autohydrolyzates. The suitability of activated charcoals as a selective adsorbent for lignin under process-relevant conditions (150 and 170°C) has not been considered up to now, because former experiments showed decreasing efficiency of charcoal adsorption of lignin with increasing temperature in the range 20–80°C. In contrast to these results, we demonstrated that the adsorption of lignin at 170°C directly after autohydrolysis is even more efficient than after cooling the hydrolyzate to room temperature. The formation of lignin precipitation and incrustations can thus be efficiently prevented by the HiTAC process. The carbohydrates in the autohydrolysis liquor remain unaffected over a wide charcoal concentration range and can be further processed to yield valuable products.

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Whey Utilization: Sustainable Uses and Environmental Approach

Food Technology and Biotechnology ◽

10.17113/10.17113/ftb.59.02.21.6968 ◽

2021 ◽

Vol 59 (2) ◽

Author(s):

Elizabeta Zandona ◽

Marijana Blažić ◽

Anet Režek Jambrak

Keyword(s):

Whey Proteins ◽

Organic Matter Content ◽

Value Added ◽

Edible Films ◽

Matter Content ◽

Raw Material ◽

Sustainable Utilization ◽

The Past ◽

Food Applications ◽

Value Added Products

The dairy industry produces large amounts of whey as a by- product or co-product, which has led to considerable environmental problems due to its high organic matter content. Over the past decades, possibilities of more environmentally and economically efficient whey utilisation have been studied, primarily to convert unwanted end products into a valuable raw material. Sustainable whey management is mostly oriented to biotechnological and food applications for the development of value-added products such as whey powders, whey proteins, functional food and beverages, edible films and coatings, lactic acid and other biochemicals, bioplastic, biofuels and similar valuable bioproducts. This paper provides an overview of the sustainable utilization of whey and its constituents, considering new refining approaches and integrated processes to covert whey, or lactose and whey proteins to high value-added whey-based products.

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Sustainable Rice Straw Management Using Pyrolysis-Extraction Process Towards Value-Added Products

SSRN Electronic Journal ◽

10.2139/ssrn.3607813 ◽

2020 ◽

Author(s):

Neda Asasian Kolur ◽

Eisa Khoshnood Motlagh ◽

Seyedmehdi Sharifian ◽

Azadeh Ebrahimian Pirbazari

Keyword(s):

Rice Straw ◽

Value Added ◽

Extraction Process ◽

Straw Management ◽

Value Added Products

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Kinetic Study of Acid Hydrolysis of Rice Straw

ISRN Biotechnology ◽

10.5402/2013/170615 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5 ◽

Cited By ~ 8

Author(s):

Nibedita Sarkar ◽

Kaustav Aikat

Keyword(s):

Reaction Time ◽

Acid Hydrolysis ◽

Rice Straw ◽

Main Product ◽

Value Added ◽

Dilute Acid ◽

Dilute Acid Hydrolysis ◽

Xylose Production ◽

Hydrolysis Of ◽

Value Added Products

Rice straw is a renewable, cheap, and abundant waste in tropical countries. The pentose content of rice straw can be used as a substrate for many types of value-added products such as xylitol and biofuel. Dilute acid hydrolysis mainly releases pentose from rice straw. The objective of the study was to determine the effect of H2SO4 concentration and reaction time on the xylose production. The variation of the main product xylose with the reaction time was described by a kinetic model and kinetic parameters were calculated to describe the variation of the xylose production with time. The optimum yield (19.35 g/L) was obtained at 0.24 mol/L H2SO4 and 30 minutes.

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Improving the fermentability of pre-hydrolysis liquor to produce ethanol and xylonic acid by removing fermentation inhibitors using polystyrene divinylbenzene resin

10.21203/rs.3.rs-70189/v1 ◽

2020 ◽

Author(s):

Caoxing Huang ◽

Wenqian Lin ◽

Yuxuan Shi ◽

Yayue Zheng ◽

Qiang Yong

Keyword(s):

Ethanol Production ◽

Acid Hydrolysis ◽

Value Added ◽

Fermentation Inhibitors ◽

Waste Streams ◽

Xylonic Acid ◽

Soluble Lignin ◽

Xylose Concentration ◽

Resin Treatment ◽

Value Added Products

Abstract Background The existences of soluble lignin, furfural and HMF in industrial pre-hydrolysis liquor (PHL) can inhibit its bioconversion into bioethanol and other bio-chemicals. Although various technologies have been carried out to remove these inhibitors, a undesirable sugars removal is also happened during the process. Hence, polystyrene divinylbenzene (PS-DVB) resin was used as adsorptive material to simultaneously remove fermentation inhibitors while retain sugars with higher yield for improving the fermentability of PHL after acid-hydrolysis (A-PHL) treatment. The fermentability of treated PHL was evaluated by the bioconversion into ethanol and xylosic acid (XA). Results Results showed that an highest xylose concentration (101.1 g/L) in PHL could be obtained by acid-hydrolysis at 100 oC for 80 min with 4% acid, while concentration of fermentation inhibitors (furfural, HMF and lignin) could also be significantly improved. After treating, not only 97% of lignin, 92% of furfural, and 97% of HMF were removed from solution, but also 96% of xylose was retained for subsequent fermentation. With resin treatment, the fermentability of A-PHL could be improved by 162–282% for ethanol production from A-PHL with 30–50 g/L xylose and by 18–828% for XA production from A-PHL with 90–150 g/L xylose. Conclusions These results confirmed that PS-DVB resin can remove inhibitors from PHL before producing value-added products by bioconversion. In addition, the work will ideally provide a concept by which pulping facilities could go about producing value-added chemicals from existing waste streams.

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OPTIMIZATION OF XYLAN EXTRACTION PROCESS FROM RICE STRAW FOR PRODUCTION OF AUTOHYDROLYSATES RICH IN PREBIOTIC XYLOOLIGOSACCHARIDES

Cellulose Chemistry and Technology ◽

10.35812/cellulosechemtechnol.2021.55.86 ◽

2021 ◽

Vol 55 (9-10) ◽

pp. 1001-1017

Author(s):

PUNEET KAUR ◽

◽

RAMANDEEP KAUR ◽

Keyword(s):

Sulphuric Acid ◽

Rice Straw ◽

Agricultural Waste ◽

Lactobacillus Rhamnosus ◽

Value Added ◽

Extraction Process ◽

Degree Of Polymerization ◽

Experimental Yield ◽

Immense Potential ◽

Value Added Products

Rice straw, an abundant agricultural waste, possesses immense potential to serve as renewable, eco-friendly and non-edible feedstock to generate value-added products. Therefore, the present study aimed to obtain prebiotic neutral xylooligosaccharides (XOS)-rich autohydrolysate from rice straw xylan. The central composite design of response surface methodology was employed to optimize the conditions for the alkaline extraction of xylan, i.e. NaOH concentration (6-14%, w/v), reaction time (1-3.5 h) and temperature (50-100 °C). Autohydrolysis of xylan was carried out at 121 °C and 15 psi for varied hydrolysis times (10, 25 and 40 min) and sulphuric acid concentrations (0.1, 0.5 and 1.0M) to obtain XOS-rich autohydrolysate. The optimum conditions were found to be as follows: 11.04% (w/v) NaOH, 3.126 h and 80.146 °C, so that the maximum xylan yield of 19.97% was predicted by the software. This value was quite close to the experimental yield of 19.4%, with 80.83% xylan being recovered per gram of rice straw. The best autohydrolysis treatment for xylan was found to be using 0.1M sulphuric acid for 10 min, which allowed 34.5% of 100 mg xylan to be depolymerized to produce neutral XOS (degree of polymerization up to 7), with xylose, xylobiose and xylotriose constituting 4.45, 10.14 and 7.83 mg, respectively. These autohydrolysates promoted higher growth of Lactobacillus rhamnosus and Lactobacillus casei than established prebiotic fructooligosaccharides. The study attempts to solve disposal issues of rice straw through production of XOS-rich autohydrolysates in demand on the global nutraceuticals market.

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Silica extraction from integrated refinery of rice straw for production of value-added products

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/337/1/012016 ◽

2019 ◽

Vol 337 ◽

pp. 012016

Author(s):

Cuong Thai Dinh ◽

Hung Nguyen Duy ◽

Dien Le Quang ◽

Lubov A. Zenitova ◽

Thanh Nguyen Trung

Keyword(s):

Rice Straw ◽

Value Added ◽

Value Added Products

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A comparative study of ionothermal treatment of rice straw using triflate and acetate-based ionic liquids

10.21203/rs.3.rs-1005503/v2 ◽

2021 ◽

Author(s):

K.J. Jisha ◽

Sunita Rajamani ◽

Dharmendra Singh ◽

Gyanendra Sharma ◽

Ramesh L. Gardas

Keyword(s):

Ionic Liquids ◽

Comparative Study ◽

Rice Straw ◽

Biomass Conversion ◽

Value Added ◽

Structural Modifications ◽

Bond Breakage ◽

Biomass Materials ◽

Common Anion ◽

Value Added Products

Abstract Ionic liquids (ILs) have found applications in the pretreatment of waste lignocellulosic biomass by interacting with the carbohydrate molecules present in the biomass materials. Pretreatment is essential before biomass conversion into valuable chemicals, fuels, and many other value-added products. This comparative study mainly focused on the pretreatment ability of four ILs having acetate or triflate as a common anion with different cations. Among various studied ILs, diazabicyclo[5.4.0]undec-7-ene (DBU)-based acidic ionic liquid when used as a dual solvocatalyst showed significant structural modifications of the rice straw (RS) sample, through C6-O bond breakage assisted by the tertiary nitrogen in DBU cation. Structural modifications due to the pretreatment were confirmed through SEM, PXRD, and FTIR analysis. The elemental analysis confirmed that carbon content in original RS is reduced to 29% and 20% upon ionothermal treatment of RS with IL at 90 °C and 120 °C, respectively. Additionally, TGA indicated that further pyrolysis could be easier with the pretreated rice straw yielding biochar up to 9% thereby reducing wastes. Conversion of RS was found to be 60 % which reduced marginally to 50 % after three cycles of recycling IL. The findings of this work provide the proof of concept that studied ILs with high thermal stability and recyclability should act as a potential solvocatalyst in sustainable pretreatment and other biomass applications.

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OPPORTUNITIES FOR STRATEGIC DEVELOPMENT OF BIO-ECONOMY IN THE FOOD AND TOURISM INDUSTRY

Knowledge International Journal ◽

10.35120/kij28051681g ◽

2018 ◽

Vol 28 (5) ◽

pp. 1681-1684

Author(s):

Georgi Toskov ◽

Ana Yaneva ◽

Stanko Stankov ◽

Hafize Fidan

Keyword(s):

National Level ◽

Value Added ◽

Tourism Industry ◽

Small Companies ◽

Food Sector ◽

Strategic Development ◽

Innovation Potential ◽

Wide Range ◽

Foreign Brands ◽

Value Added Products

The European Commission defines the bioeconomy as "the production of renewable biological resources and the conversion of these resources and waste streams into value added products, such as food, feed, bio-based products and bioenergy. Its sectors and industries have strong innovation potential due to their use of a wide range of sciences, enabling and industrial technologies, along with local and implied knowledge." The Bulgarian food industry faces a lot of challenges on the local and national level, which have direct influence on the structure of the production companies. Most of the enterprises from the food sector produce under foreign brands in order to be flexible partners to the large Bulgarian retail chains. The small companies from the food sector are not able to develop as an independent competitive producer on the territory of their local markets. This kind of companies rarely has a working strategy for positioning on new markets. In order to consolidate their already built positions for long period of time, the producers are trying to optimize their operations in a short term. However, the unclear vision of the companies for the business segment does not allow them to fully develop. Tourism in Bulgaria is a significant contributor to the country's economy.

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