Recently, the bioconversion of biomass into biofuels and biocommodities has received significant attention. Although green technologies for biofuel and biocommodity production are advancing, the productivity and yield from these techniques are low. Over the past years, various recovery and purification techniques have been developed and successfully employed to improve these technologies. However, these technologies still require improvement regarding the energy-consumption-related costs, low yield and product purity. In the context of sustainable green production, this review presents a broad review of membrane purification technologies/methods for succinic acid, a biocommodity obtained from lignocellulosic biomass. In addition, a short overview of the global market for sustainable green chemistry and circular economy systems or zero waste approach towards a sustainable waste management is presented. Succinic acid, the available feedstocks for its production and its industrial applications are also highlighted. Downstream separation processes of succinic acid and the current studies on different downstream processing techniques are critically reviewed. Furthermore, critical analysis of membrane-based downstream processes of succinic acid production from fermentation broth is highlighted. A short review of the integrated-membrane-based process is discussed, as well, because integrating “one-pot” lignocellulosic bioconversion to succinic acid with downstream separation processing is considered a critical issue to address. In conclusion, speculations on outlook are suggested.

This study exploited the solvent extraction and mechanical agitation techniques for the remediation of soils contaminated with polycyclic aromatic hydrocarbons (PAHs). The removal of pollutants from diesel contaminated site through ethanol, hexane, and ethanol-hexane mixtures was evaluated. 50 g dried contaminated soil was placed in a Soxhlet extractor and 250 ml solvent (ethanol, or hexane, or ethanol-hexane mixture) was added with extraction occurring at different temperatures of 30, 35, 45, 50, and 60 °C for 16 h. Mechanically agitated method was carried out by weighing out an equal amount of 50 g of the contaminated soil, thoroughly washing with 250 ml of ethanol, hexane, and equal ratio of ethanol to hexane. Qualitative analysis recovered PAHs was done by Agilent series gas chromatography equipped with flame ionization detector. The chromatographic evaluations of the solvent extraction of the contaminated soil showed that more of the polluted compounds were removed when hexane was the solvent. The maximum yield of extracted diesel by the solvent hexane was 11.84% at 60 °C. Extracted diesel removal was also directly proportional to periods of extraction.

Background and Objectives: The choice of a suitable pretreatment method and the adjustment of the pretreatment parameters for efficient conversion of biomass to value-added products is crucial to a successful biorefinery concept. Pretreatment of corn cob using ZnCl2.4H2O/ Urea was carried out and optimized in this study. Methods: Effect of pretreatment conditions on cellulose recovery, hemicellulose recovery during the pretreatment of corn cob using ZnCl2.4H2O/ Urea was investigated via response surface methodology approach and optimized in this study. Experimental results were analysed and appropriate predictive empirical linear models were developed for each response. Results: For cellulose recovery, time and temperature, and solvent concentration were significant factors. Hemicellulose recovery in the liquid fraction is impacted by time and solvent concentration, while lignin recovery is affected by time and temperature. Using numerical optimization by desirability function, optimum pretreatment conditions obtained were: 90 min, 120°C and concentration of 71.32%/28.68 (w/w) ZnCl2.4H2O/ Urea. At these conditions, the predicted recovery for cellulose, hemicellulose and lignin were 99.03%, 27.18% and 72.43%, respectively, with a desirability of 0.902. The actual recovery was 91%, 29% and 68% for cellulose, hemicellulose and lignin, respectively, at the same conditions. Conclusion: These results indicate that the investigated variables have pronounced effect on the pretreatment of corn cob. Therefore, optimum conditions are required for recovery of desired composition before conversion to value-added products.

Major concern in beneficiating lignocellulose is overcoming biomass recalcitrance through pre-treatment. Molten hydrate salts (MHS) is a green solvent with ability to swell and dissolve cellulose and biomass in a non-derivatizing way. Over the last decade, MHSs have been used for isolated cellulose dissolution, however very few studies have been reported on their effectiveness in pre-treating lignocellulosic biomass. Therefore, effectiveness of their application as solvent for pre-treating and fractionating corn cob is presented in this article. In this study, seven molten hydrate salt pre-treatment solvent systems such as unary, binary and ternary mixtures of ZnCl2.4H2O, LiClO4.3H2O and Urea were investigated for their ability to pre-treat and fractionate biomass. The pre-treatment experiments were carried out in a shaking incubator at 70°C for 60 minutes at a biomass: solvent ratio of 1:10. The surface chemistry of the biomass was checked before and after pretreatment using Fourier Transform infrared spectroscopy. X-ray diffraction and scanning electron microscopy were employed to check the crystallinity and surface morphology of the biomass. Physicochemical analysis consistently indicated a disruption in the structure of corncob due to removal of lignin and hemicellulose during the pre-treatment process. Additionally, results showed a decrease in crystallinity and a change in surface morphology after the pre-treatment using all the seven solvent systems (MHS solvents). The use of ZnCl2.4H2O/ Urea solvent displayed 100% recovery of cellulose, 42% recovery of hemicellulose and 44% recovery ABOUT THE AUTHORS

This paper looked at the potential and available alternative conversion paths for fuels and chemicals production away from the conventional conversion processes of fossil based fuels. Lignocellulosic biomasses are abundant, renewable, and domestically available energy resources. Though with its own attendant challenges, there are achievements and prospects that have been made in developing environmentally friendly processes for small and large scale conversion of lignocelluloses to different fuels and chemicals. With the continuous reliance on fossil fuels, there is the ever increasing climate change caused by the increasing greenhouse gas emissions such as carbon dioxide. Biomass from marine, trees, plants, animal wastes, food and non- food crops, grains, and wood based can produce fuels such as ethanol, butanol, and other chemicals through some promising technologies. Therefore, identifying ways to improving production efficiency of fuels and chemicals during biomass conversion processes to a sustainable level is very crucial.