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Miscanthus Biomass for Alternative Energy Production
Published in Larry E. Erickson, Valentina Pidlisnyuk, Phytotechnology with Biomass Production, 2021
Jikai Zhao, Donghai Wang, Valentina Pidlisnyuk, Larry E. Erickson
Organosolv and ionic liquids as green solvents offer the advantage of clean fractionation of lignocellulosic biomass into individual components with high purity (Brosse et al., 2009; Dash & Mohanty, 2019; Kim et al., 2018). Organosolv allows for the efficient fractionation of starting biomass into a solid residue rich in cellulose and a liquid fraction containing organosolv and water-soluble lignin and hemicellulose (Brosse et al., 2009). Ionic liquids owing hydrogen bond acceptor with high polarity can dissolve Miscanthus biomass, and ionic liquids having acetate, chloride, and phosphate anions show desirable solubility properties (Padmanabhan et al., 2011). However, excessive reagents are consumed for washing pretreated biomass to avoid lignin recondensation. Besides, the sealed condition required for organosolv and ionic liquid recoveries increases production costs, limiting their feasibility in commercialization.
Ionic Liquids for Biomass Processing
Published in Pedro Lozano, Sustainable Catalysis in Ionic Liquids, 2018
Wei-Chien Tu, Jason P. Hallett
The organosolv process uses organic solvents, such as ethanol, acetone, ethylene glycol, formic, and acetic acid between 160°C and 200°C and pressure from 5 bar–30 bar to break down lignin and hemicellulose.37 This pretreatment method is versatile and has been commercially developed for papermaking, as well as bioethanol production.38 The solvent is recyclable and reusable, however, the pulps require cumbersome wash steps because most of the solvents are toxic to microorganisms or inhibitory to enzymes.37,39 In addition, processing the large quantities of highly flammable solvents at elevated temperatures and pressures presents a safety concern.40 Organosolv does have some advantages over kraft pulping in that it produces less air and water pollution.41
Pretreatment of Biomass
Published in Charles E. Wyman, Handbook on Bioethanol, 2018
Solvent. Use of an organic solvent such as methanol, ethanol, or acetone to solubilize and remove lignin (known as the organosolv process) has been reported [27,34,134–139]. An organosolv process in the presence of an acid or alkali catalyst has also been studied [27,136,137,139,140]. Organosolv processes are delignification processes, with varying degrees of simultaneous hemicellulose removal, as discussed earlier. When a catalyst is used, hemicellulose solubilization increases and the digestibility of pretreatedbiomass is enhanced [136]. However, because organic solvents are costly and their use requires high-pressure equipment, the organosolv process is perceived as complex and expensive [141]. Aziz and Sarkanen [142] reviewed organosolv processes for pulping and concluded that they are too costly to replace conventional pulping methods. One organosolv process, the ALCELL process, has been advanced to industrial demonstration level [28,143] but, again, is not for ethanol production.
Mutual compatibility aspects and rheological assessment of (modified) lignin–bitumen blends as potential binders for asphalt
Published in Road Materials and Pavement Design, 2022
Sayeda Nahar, Ted M. Slaghek, Dave van Vliet, Ingrid K. Haaksman, Richard J.A. Gosselink
There are several methods to extract lignin from the biomass. The main reason for this extraction is to produce the much-needed cellulose fibre, e.g. the production of paper (Mboowa, 2021). The paper and pulp industry are therefore the largest producers of lignin-rich side streams. The most common chemical process used to extract lignin is the Kraft process which is also known as the sulphate process. Kraft process was developed in the second half of the nineteenth century (Dahl, 1884), since then it has become the extraction method of choice for the production of cellulose fibres (Chakar & Ragauskas, 2004; Demuner et al., 2019; Dessbesell et al., 2020; Gellerstedt, 2015). Over the decades, other extraction processes have also been developed such as Organosolv extraction using methods such as ethanol/water at elevated temperature or the use of formic acid (Aziz & Sarkanen, 1989; Borand & Karaosmanoglu, 2018; Fernández-Rodríguez et al., 2017; Ferreira & Taherzadeh, 2020; Zhao et al., 2009). These extraction methods are partly still in the pilot phase and some companies are currently building the first generation production plants.
Recent progress in the conversion of biomass wastes into functional materials for value-added applications
Published in Science and Technology of Advanced Materials, 2020
Cellulose is the most abundant polymer, representing approximately 40–50% of plant and woody biomass by weight [82]. Cellulose exhibits a high strength and is renewable and biodegradable, so it is widely used for fabricating optical films, coatings, and controlled released systems, as well as in textile and paper industries [83]. Mechanical, chemical, biological, enzymatic, and their combination treatments are common methods to extract cellulose from biomass wastes [84]. Substances like hemicellulose and lignin are removed by multistep treatments and cellulose is then obtained with high purity. Compared to single treatment, combination of mechanical, chemical, and biological treatments can increase the quality of cellulose; however, it increases the cost and causes high-energy consumption. For example, Kumneadklang et al. [66] treated OPF with NaOH solution with various concentrations under pressure of 7 bar and non-pressure (1.013 bar). It was found that α-cellulose fibers with highest content (91.33%) and crystallinity (77.78%) were obtained by using 15 wt.% NaOH at 150°C and 7 bar. Except from combination of treatments, it has been reported that organosolv process is a promising approach for the pretreatment of biomass wastes, because the lignocellulosic structure can be broken down and fragmented, and the constituents (e.g. cellulose, lignin, and hemicellulose) are subsequently isolated with high purity. For example, Amaral et al. [13] isolated cellulose from babassu coconut shells through organosolv with an acid catalyst, and the yield was about 70–95%. Comparison with conventional pulping processes (e.g. Kraft process and sulfite process) with yields of 50–60% [85], these new isolation processes are faster, more effective, and less harmful to the environment.
A critical process variable-regulated, parameter-balancing auxostat, performed using disposed COVID-19 personal protective equipment-based substrate mixture, yields sustained and improved endoglucanase titers
Published in Preparative Biochemistry & Biotechnology, 2023
Navnit Kumar Ramamoorthy, Revanth Babu Pallam, Kabilan Subash Chandrabose, Renganathan Sahadevan, Venkateswara Sarma Vemuri
The disposed COVID-19 PPE and other hospital-related wastes had remained soaked in a commercially-available disinfectant solution, before collection. The disinfectant contained an ∼70% (v/v) of ethanol. While autoclaving during pre-processing, the substrate mixture had undergone an unintended autoclave-assisted organosolv pretreatment.[52] Proximate analysis of the pre-processed substrate mixture revealed that the pretreatment effected (in w/w): (i) 4.5% increase in cellulose; (ii) 2.5% degradation of lignin; (iii) 4.43% solubilization of hemicelluloses (Supplementary Table 1). In general, an organosolv pretreatment efficiently fractionates lignocellulosic biomass into cellulose, hemicellulose, and lignin.[53] As ethanol in the disinfectant solution percolates into the interior of the substrate mixture, it disrupts the ether’s α and β aryl linkages,[54] causing considerable lignin depolymerization. This degradation was visually-assessed during SEM observations (Figures 4a,b). An uneven/rough surface of the pre-processed substrate mixture was observed (Figure 4b), which is a notable consequence of lignin dissolution and depolymerization.[55] Additionally, differences between distinctive peak intensities of the FT-IR spectra of the unprocessed (Figure 5a) and pre-processed substrate mixture (Figure 5b) revealed the changes, which are being mentioned in the ensuing statements. The spectral range between 1390 and 1310 cm−1 corresponds to bending of O-H groups of the phenolic units of lignin.[56] The region between 1640 and 1600 cm−1 corresponds to lignin’s C=C aromatic ring vibrations.[57] The spectral range between 1150 and 1085 cm−1 corresponds to the stretching of the C–O bonds of aliphatic ether. Post pretreatment, increases of transmittances in the above-mentioned regions substantiate the fact of lignin removal (Figures 5a,b). A chemical hydrolysis of the glycolytic bonds causes hemicellulose’s and cellulose’s deconstruction.[53] Considerable disentanglement and destruction of the integrity of the cellulosic fibers are visible in the SEM images (Figure 4b).[57] In Figures 5a,b, sugar hydrolysis was confirmed by variations between the characteristic FT-IR spectral regions. The region between 1373 and 1319 cm−1 pertains to vibrations related to C–H deformations of the constructing-units of cellulose and hemicellulose.[58] The spectral region 1740–1720 cm−1 corresponds to stretching-vibrations among C=O of carboxylic acid or acetyl groups, which constitute hemicelluloses.[56] The spectral region between 1210 and 1163 cm−1 corresponds to the ester groups’ O–C=O stretching, which is unique to bonds of hemicelluloses.[56] Considerable increases in transmittances of the above-mentioned spectral regions of the pretreated biomass add evidence to the fact of biomass deconstruction.