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Carboxymethyl cellulose (CMC) is one of the important cellulose derivatives, and it can be developed as a host polymer for solid polymer electrolyte (SPE) membrane. This study aimed to synthesis of CMC from coconut fiber cellulose and it was applied to prepare the SPE membranes. Cellulose isolation was conducted through the delignification and bleaching process, while the CMC synthesis was conducted through alkalization and carboxymethylation treatments. SPE membranes were prepared by blending CMC with carboxymethyl chitosan (CMCh) (80/20) and mixed with various weight percentages of LiOAc at room temperature. SPE membranes characterizations were conducted using FTIR, EIS, XRD, SEM, and tensile testing. Cellulose and CMC yields were 23.1% and 65.44%, respectively. Incorporating 20 wt% LiOAc into the CMC/CMCh (80/20) SPE membrane yielded the highest ionic conductivity of 1.37 × 10−3 S/cm. Based on the results, CMC obtained from coconut fibers has the potential to produce solid polymer electrolyte membranes with some modification. [ABSTRACT FROM AUTHOR]

Indonesia is the largest palm plantation that reaches 32 million tonnes palm oil production per year with 84 million tones Palm Oil Mill Effluent (POME) as liquid waste. POME contains many organic substances. The quality of POME for its utilization is generally measured in COD which has range 30000 -100.000 ppm. Microbial convertion for biogas especially for bio-H2 enrichment, the active sludge was pretreated physically to suppress methanogenesis microbes. H2 Biogas production was conducted at pH 5-6. Additional 10% phosphate buffer was done in the beginning only. The production of H2 biogas was influenced by hydrostatic pressure in closed batch system. Inoculumsmedium ratio also influenced the H2 biogas productivity, reached 0.7 ml/ml POME with more than 50% H2. Scaling up anaerobic in 2.5 L working volume bioreactor, H2 biogas productivity reached 0.86 ml/ml POME by 10% inoculums because of no hydrostatic pressure. In bio-reactor, H2-CO2 in H2 biogas was affected by the amount of active sludge. In the beginning of H2 biogas, H2 reached 80%. However, at subsequence process, fed batch, with retention time 2.5 day and 3 days H2 biogas production, the active sludge was accumulated and caused the decreasing H2, finally only 46% at the 3rd day. The consortium tended to produce more CO2 as the result of primary metabolite rather than H2. Raising inoculums to level 15% improved productivity only in the beginning but H2 content was getting less, only 59%. Additional feeding would cause more accumulation sludge and more decreasing H2 content to 31% on the 3rd day. Thus, the ratio of active sludge and substrate availability must be controlled to gain optimum H2. Limited substrate will cause the direction of bio-conversion more in CO2 rather than H2.

Biomass waste has been emerging as an alternative energy and fuel. Direct combustion of biomass leads to harmful substances such as NOx and CO which are environmentally unfriendly manner. Innovation of clean technologies like gasification would have a potential in developing technology to reduce the emissions of harmful substances into the environment. The syngas of biomass gasification is an intermediate product which can be converted further to various types of alternative fuels especially methanol. Agency for the Assessment and application of Technology (BBPT)-Indonesia in cooperation with Gunma University-Japan has been conducting assessment and application of environmentally friendly solid biomass wastes utilization technology under the SATREPS (Science and Technology Research Partnership for Sustainable Development) program. This work is a prolongation of biomass gasification process from empty fruit bunches (EFB) to produce syngas. Furthermore, the syngas has a potential as raw material to synthesize methanol. The study of methanol synthesis focused on the development of efficient and low-cost catalyst in term of low pressure and low temperature. The catalyst of methanol synthesis was prepared by co-precipitation method with copper basis. The experiments have been performed and tested in a once-through process by Low-Pressure Fixed Bed Reactor in Micromeritics unit at a mild operating condition. The result shows that catalyst CuO: ZnO: Al2O3 (47%: 37%: 15%) has a good performance at 20 bar and 270°C with methanol concentration in the gas product up to 1.15%. On the words, the local catalyst performance comparable with commercial catalysts at low pressure and low temperature.

Abstract Background Ethanol production from paper sludge (PS) by simultaneous saccharification and fermentation (SSF) is considered to be the most appropriate way to process PS, as it contains negligible lignin. In this study, SSF was conducted using a cellulase produced from PS by the hypercellulase producer, Acremonium cellulolyticus C-1 for PS saccharification, and a thermotolerant ethanol producer Saccharomyces cerevisiae TJ14 for ethanol production. Using cellulase of PS origin minimizes biofuel production costs, because the culture broth containing cellulase can be used directly. Results When 50 g PS organic material (PSOM)/l was used in SSF, the ethanol yield based on PSOM was 23% (g ethanol/g PSOM) and was two times higher than that obtained by a separate hydrolysis and fermentation process. Cellulase activity throughout SSF remained at around 60% of the initial activity. When 50 to 150 g PSOM/l was used in SSF, the ethanol yield was 21% to 23% (g ethanol/g PSOM) at the 500 ml Erlenmeyer flask scale. Ethanol production and theoretical ethanol yield based on initial hexose was 40 g/l and 66.3% (g ethanol/g hexose) at 80 h, respectively, when 161 g/l of PSOM, 15 filter paper units (FPU)/g PSOM, and 20% inoculum were used for SSF, which was confirmed in the 2 l scale experiment. This indicates that PS is a good raw material for bioethanol production. Conclusions Ethanol concentration increased with increasing PSOM concentration. The ethanol yield was stable at PSOM concentrations of up to 150 g/l, but decreased at concentrations higher than 150 g/l because of mass transfer limitations. Based on a 2 l scale experiment, when 1,000 kg PS was used, 3,182 kFPU cellulase was produced from 134.7 kg PS. Produced cellulase was used for SSF with 865.3 kg PS and ethanol production was estimated to be 51.1 kg. Increasing the yeast inoculum or cellulase concentration did not significantly improve the ethanol yield or concentration.

A subclass of Metal-Organic Frameworks, Zeolitic Imidazole Frameworks-8 (ZIF-8) is known as an emerging material that has the characteristic of a large surface area, good thermal stability as well as a high porosity. Instead of having extraordinary properties, ZIF-8 consists of Lewis acid and Lewis base site on its Zn metals and 2-methylimidazole which are the important components for the catalyst. In this study, Pd-Poly(N-vinyl-2-pyrrolidone) coated on ZIF-8 (Pd-PVP@ZIF-8) was synthesized by mixed Pd-PVP solution and ZIF-8 precursors at room temperature. The Pd-PVP solution was varied from 10 to 50 ml to differentiate the Pd concentration in ZIF-8. As-synthesized 50 ml of Pd-PVP on ZIF-8 (50Pd-PVP@ZIF-8) showed catalytic activity in the conversion of 98.6% lauric acid to produce 78.2% of 1-dodecanol at optimum condition 320 °C for 6 h. The synergy between Pd-PVP as metal and ZIF-8 as metal support as well as high dispersion of Pd particles could enhance performance in the conversion of lauric acid. [ABSTRACT FROM AUTHOR]

Background: Ethanol production from paper sludge (PS) by simultaneous saccharification and fermentation (SSF) is considered to be the most appropriate way to process PS, as it contains negligible lignin. In this study, SSF was conducted using a cellulase produced from PS by the hypercellulase producer, Acremonium cellulolyticus C-1 for PS saccharification, and a thermotolerant ethanol producer Saccharomyces cerevisiae TJ14 for ethanol production. Using cellulase of PS origin minimizes biofuel production costs, because the culture broth containing cellulase can be used directly., Results: When 50 g PS organic material (PSOM)/l was used in SSF, the ethanol yield based on PSOM was 23% (g ethanol/g PSOM) and was two times higher than that obtained by a separate hydrolysis and fermentation process. Cellulase activity throughout SSF remained at around 60% of the initial activity. When 50 to 150 g PSOM/l was used in SSF, the ethanol yield was 21% to 23% (g ethanol/g PSOM) at the 500 ml Erlenmeyer flask scale. Ethanol production and theoretical ethanol yield based on initial hexose was 40 g/l and 66.3% (g ethanol/g hexose) at 80 h, respectively, when 161 g/l of PSOM, 15 filter paper units (FPU)/g PSOM, and 20% inoculum were used for SSF, which was confirmed in the 2 l scale experiment. This indicates that PS is a good raw material for bioethanol production., Conclusions: Ethanol concentration increased with increasing PSOM concentration. The ethanol yield was stable at PSOM concentrations of up to 150 g/l, but decreased at concentrations higher than 150 g/l because of mass transfer limitations. Based on a 2 l scale experiment, when 1,000 kg PS was used, 3,182 kFPU cellulase was produced from 134.7 kg PS. Produced cellulase was used for SSF with 865.3 kg PS and ethanol production was estimated to be 51.1 kg. Increasing the yeast inoculum or cellulase concentration did not significantly improve the ethanol yield or concentration.