Chemical Pretreatment And Enzymatic Hydrolysis Of Mixed Source-Separated Organic (SSO) And Wood Waste

This paper examines the effectiveness of two pretreatments on Source-Separated Organic waste (SSO) mixed with wood wastes: long term lime for SSO mixed with forestry waste (hardwoods), and the cellulose solvent-organic lignocellulose fractionation (COSLIF) method, with SSO and demolition waste (softwoods). For long term lime treatment, the highest overall conversions from cellulose to glucose and xylose were 50.4%, and 43.5% respectively. The best temperature found for long term lime pretreatment was 65°C. The COSLIF pretreatment glucose yield was found to be 93.7%. The highest enzyme hydrolysis yield found was 93.5% for a cellulase loading of 30 FPU/g glucan at 50°C. The best hydrolysis yield found at lower loading (10 FPT/g glucan), was 83.5%. At 40 and 50°C, all peak hydrolysis yields were achieved between 12 and 24 hours. A drop in temperature below 40°C caused a slowing of the hydrolysis rate.

Chemical Pretreatment And Enzymatic Hydrolysis Of Mixed Source-Separated Organic (SSO) And Wood Waste

This paper examines the effectiveness of two pretreatments on Source-Separated Organic waste (SSO) mixed with wood wastes: long term lime for SSO mixed with forestry waste (hardwoods), and the cellulose solvent-organic lignocellulose fractionation (COSLIF) method, with SSO and demolition waste (softwoods). For long term lime treatment, the highest overall conversions from cellulose to glucose and xylose were 50.4%, and 43.5% respectively. The best temperature found for long term lime pretreatment was 65°C. The COSLIF pretreatment glucose yield was found to be 93.7%. The highest enzyme hydrolysis yield found was 93.5% for a cellulase loading of 30 FPU/g glucan at 50°C. The best hydrolysis yield found at lower loading (10 FPT/g glucan), was 83.5%. At 40 and 50°C, all peak hydrolysis yields were achieved between 12 and 24 hours. A drop in temperature below 40°C caused a slowing of the hydrolysis rate.

Alternative Lime Pretreatment of Corn Stover for Second-Generation Bioethanol Production

In this work, a delignification process, using lime (Ca(OH)2) as an alternative alkali, was evaluated to improve enzymatic saccharification of corn stover cellulose, with the final goal of obtaining second-generation bioethanol. For that, an experimental design was conducted in order to assay the effect of temperature, lime loading, and time on the corn stover fractionation and enzymatic susceptibility of cellulose. Under conditions evaluated, lime pretreatment was selective for the recovery of cellulose (average of 91%) and xylan (average of 75.3%) in the solid phase. In addition, operating in mild conditions, a delignification up to 40% was also attained. On the other hand, a maximal cellulose-to-glucose conversion (CGCMAX) of 89.5% was achieved using the solid, resulting from the treatment carried out at 90 °C for 5 h and lime loading of 0.4 g of Ca(OH)2/g of corn stover. Finally, under selected conditions of pretreatment, 28.7 g/L (or 3.6% v/v) of bioethanol was produced (corresponding to 72.4% of ethanol conversion) by simultaneous saccharification and fermentation. Hence, the process, based on an alternative alkali proposed in this work, allowed the successful production of biofuel from the important and abundant agro-industrial residue of corn stover.

Effect of Lime Pretreatment on Microstructure of Cassava Stalk Fibers and Growth of Aspergillus niger

Cassava stalk can be converted into sugar-based product by using microorganism. Unfortunately, lignin act as a barrier of optimal bioconversion. Cassava stalk needs pretreatment process for removing this barrier. The effect of lime pretreatment on microstructure of cassava stalk fibers and the growth of Aspergillus niger FNCC 6114 were observed in this research. The cassava stalks were reduced into 0.147- 0.297 mm size and pretreated with 1 % Ca(OH)2. Lime pretreated and unpretreated cassava stalk was used as solid medium for Aspegillus niger FNCC 6114. The effect of pretreatment method on fibers microstructure of cassava stalk was evaluated through SEM micrograph. The growth and metabolism activities of Aspergillus niger FNCC 6114 were monitored through SEM micrograph of media after fermentation. The other parameters examined were changes in glucosamine, reducing sugar levels, and spores’ quantity. Lime pretreatment altered microstructure of cassava stalk fibers. However, cassava stalk without lime pretreatment gave better growth of Aspergillus niger FNCC 6144 based on metabolism activities parameters. Cassava stalks is suitable as media for Aspergillus niger FNCC 6144 through solid state fermentation. For better growth of Aspergillus niger FNCC 6144 fine-sized cassava stalk should not be lime pretreated. The results of this study provide information about the pretreatment of cassava stems which was effective in supporting the growth of Aspergillus niger. Enhancements the utilization of cassava stems by using fungi, for example Aspergillus niger can overcome the accumulation of organic waste that can interfere with environmental sustainability.