Assessment of holocellulose for the production of bioethanol by conserving Pinus radiata cones as renewable feedstock

Study of the Influence of Bamboo Suspension Water-Removal Processes on the Properties of Bamboo-Based Molding Materials

Bamboo is a fast-growing lignocellulosic plant in nature. It is an abundant and renewable resource with wide applications. The processing of bamboo results in a large amount of residue. In this paper, we developed a method to utilize bamboo residue to prepare a novel lightweight porous molding material. A hydrated thermochemical grinding process was proposed to disintegrate bamboo fibers and activate bamboo's own binding components. The influence of the water removal by pressure from bamboo suspension and subsequent different drying methods on the product's properties was evaluated. The two-step drying ensured a low production cost and high product quality. The bamboo molding material was characterized based on thermal stability, morphology, functional groups, particle size distribution, crystallinity, and mechanical strength. A lightweight porous material was obtained with a density of 0.23-0.35 g/cm3 by freeze-drying. A high mechanical strength was obtained with a tensile strength of 0.62 MPa and a compressive strength of 10.31 MPa by oven drying. The auto-adhesive mechanisms, including fiber anchorage, polymerization, water plasticization, and heat plasticization, were discussed. The bamboo molding material is a reconstruction of bamboo cell wall components and is easy to recycle. It has potential applications in construction and buildings, packaging, and indoor furnishings.

Microalgae starch: A promising raw material for the bioethanol production

Ethanol is currently the most successful biofuel and can be produced from microalgal biomass (third-generation). Ethanol from microalgal biomass has advantages because it does not use arable land and reduces environmental impacts through the sequestration of CO₂ from the atmosphere. In this way, micro and macroalgal starch, which is structurally similar to that from higher plants can be considered a promise raw material for the production of bioethanol. Thus, strategies can be used to intensify the carbohydrate concentration in the microalgal biomass enabling the production of third-generation bioethanol. The microalgae biomass can be destined to biorefineries so that the residual biomass generated from the extraction processes is used for the production of high value-added products. Therefore, the process will have an impact on reducing the production costs and the generation of waste. In this context, this review aims to bring concepts and perspectives on the production of third-generation bioethanol, demonstrating the microalgal biomass potential as a carbon source to produce bioethanol and supply part of the world energy demand. The main factors that influence the microalgal cultivation and fermentation process, as well as the processes of transformation of biomass into the easily fermentable substrate are also discussed.

Dry Bulk Carrier Investment Selection through a Dual Group Decision Fusing Mechanism in the Green Supply Chain

Uncertain linguistic variables and scoring evaluations are two important evaluation mechanisms in the decision making field. Sustainability requirements for ship investment lead to the complexity of influence factors and the decision making process. The uncertain linguistic assessment features a large amount of ambiguity and subjectivity, while the scoring evaluation features high precision and distinct gradations. This paper constructs a criteria system in the green supply chain and proposes a dual group decision fusing mechanism for integrating the linguistic variable and scoring evaluation into a unified evaluation term. A hierarchical cloud of linguistic variable terms is constructed based on scoring via a reverse cloud generator, and then, the ship investment linguistic terms are transformed into prospect values. In addition, the consistency and investment selection performance are measured after aggregating the individual decision matrices for group decision making. The empirical research results on the selection of dry bulk carriers for investment show that dual group decision fusing mechanisms could effectively improve the consistency, decision making efficiency, and accuracy of dry bulk ship investment choices and reduce the cost of feedback adjustment for group decisions. In comparison with the trapezoidal fuzzy and fuzzy TOPSIS methods of group decision making, the proposed method performs better when there are a large number of alternatives.

Improvement of ethanol and biogas production from sugarcane bagasse using sodium alkaline pretreatments

Sugarcane bagasse was pretreated with sodium carbonate, sodium sulfite, and sodium acetate in concentrations of 0.5 M and 0.25 M, as well as hydrothermal pretreatment, to break down its structural recalcitrance and improve biogas and ethanol production. The pretreatments were conducted at 100, 140, and 180 °C for 1 h. The highest biogas and ethanol production was observed for sugarcane bagasse pretreated with 0.5 M sodium carbonate solution at 140 °C, which was 239 ± 20 Nml CH₄/g VS, and 7.27 ± 0.70 g/l, respectively, containing gasoline equivalents of 164.2 ± 14.3 l/ton of raw bagasse and 147.8 ± 14.2 l/ton of raw bagasse, respectively. The highest gasoline equivalent was obtained for biogas production from the substrate pretreated with 0.5 M sodium sulfite solution at 100 °C (190.2 ± 2.1 l/ton of raw bagasse). In comparison to sodium carbonate and sodium sulfite, sodium acetate had less effect on biofuel production and was comparable with hydrothermal pretreatment. In contradiction to sodium acetate pretreated bagasse, in which increased pretreatment temperature intensified biofuel production, a reduction of biofuel production was observed for sodium carbonate and sodium sulfite pretreatment when temperature was increased from 140 to 180 °C. Besides considerable amounts of biofuel production at the best conditions obtained, over 762 and 543 kilotons of equivalent CO₂ can be reduced annually in Iran by biogas and ethanol production from sugarcane, respectively.

Chemically synthesized biofuels from agricultural waste: Optimization operating parameters with surface response methodology (CCD)

Bioethanol is one of the most important alternative renewable energy sources that substitute the fossil fuels. Sugarcane bagasse has a content of cellulose and hemicelluloses, which make it suitable as fermentation substrate when hydrolyzed. The objective of work is ethanol production from sugarcane bagasse (SCB) by the fermentation process. Eight laboratory experiments were conducted to produce bioethanol from sugarcane bagasse. By using Design Expert, it was formulated the dilute acid hydrolysis step to investigate the effects of hydrolysis parameters on a yield of ethanol and optimum condition. All the three hydrolysis parameters were significant variables for the yield of ethanol. The optimum combinations of the three factors maximum ethanol yield were 10.86 ml at 50 g sample, 92.59 °C hydrolysis temperature, 30 min hydrolysis time and 1%v/v acid concentration. From this study following point were concluded: •Lignocellulosic containing material are sustainable for clean energy production•Production of bioethanol from waste sugarcane baggage's is possible•Operating parameters (time, temperature and acid concentration) can be optimized by surface response methodology.•Process parameters hydrolysis, fermentation and distillation have significant role on bioethanol yield.

Design of a selective solid acid catalyst for the optimization of glucose production from Oryza sativa straw

A selective, green and fast method for the production of glucose from rice (Oryza sativa) straw is demonstrated.