Catalytic Conversion of Wastewater from Starch Industry to Levulinic Acid

Levulinic acid is known as versatile building block for the production of energy and various petrochemical products. In this present work, levulinic acid was produced by dehydration and rehydration of sugar-rich wastewater containing H2SO4 from starch industry. This study proposed feasibility of utilizing waste water that obtained from nano-crystalline process of starch factory as resource for the production of levulinic acid without catalyst adding. The influence of reaction time and reaction temperature to yield of levulinic acid were investigated. It was found that the highest yield of levulinic acid was 91.41 mol % at 140 °C with the reaction time of 240 min. Keywords: Levulinic acid, wastewater, renewable, energ

Hydro-Fractionation for Biomass Upgrading

Lignocellulosic biomass is mainly composed of three components including cellulose, hemicellulose, and lignin. A fractionation step is considered as one of the most important preliminary processes for the separation of these three components before their further utilization. Among different separation techniques, water-based pretreatments or hydro-fractionations including (a) subcritical water extraction, (b) supercritical water extraction, and (c) steam explosion have shown their promising advantages both in terms of separation efficiency and in terms of environmental friendliness. Several hydro-fractionation technologies have been developed during the last decade in which each fractionation process has different impacts on the compositional and structural features of biomass. The fractionation principle, current status, and their potential uses in the biorefinery for sugar-based chemical platform production are mainly discussed

Development of Photothermal Catalyst from Biomass Ash (Bagasse) for Hydrogen Production via Dry Reforming of Methane (DRM): An Experimental Study

Conventional hydrogen production, as an alternative energy resource, has relied on fossil fuels to produce hydrogen, releasing CO2 into the atmosphere. Hydrogen production via the dry forming of methane (DRM) process is a lucrative solution to utilize greenhouse gases, such as carbon dioxide and methane, by using them as raw materials in the DRM process. However, there are a few DRM processing issues, with one being the need to operate at a high temperature to gain high conversion of hydrogen, which is energy intensive. In this study, bagasse ash, which contains a high percentage of silicon dioxide, was designed and modified for catalytic support. Modification of silicon dioxide from bagasse ash was utilized as a waste material, and the performance of bagasse ash-derived catalysts interacting with light irradiation and reducing the amount of energy used in the DRM process was explored. The results showed that the performance of 3%Ni/SiO2 bagasse ash WI was higher than that of 3%Ni/SiO2 commercial SiO2 in terms of the hydrogen product yield, with hydrogen generation initiated in the reaction at 300 °C. Using the same synthesis method, the current results suggested that bagasse ash-derived catalysts had better performance than commercial SiO2-derived catalysts when exposed to an Hg-Xe lamp. This indicated that silicon dioxide from bagasse ash as a catalyst support could help improve the hydrogen yield while lowering the temperature in the DRM reaction, resulting in less energy consumption in hydrogen production

Corn stover-derived biochar supporting dual functional catalyst for direct sorbitol production from cellulosic materials

Sorbitol is one of the top twelve platform chemicals and is industrially produced via glucose hydrogenation reaction. Direct sorbitol production from cellulosic material using a low-cost catalyst is a current challenge. In this study, corn stover-derived biochar supporting dual functional catalyst (Ru/S-CCS) was prepared and extensively characterized. The Ru/S-CCS catalyst was used for direct sorbitol production from microcrystalline cellulose at various reaction temperatures (180–220 °C), times (3–18 h), H2 pressures (1–5 MPa), and Ru contents (1–5 %). The maximum sorbitol yield (66.3 wt%) and selectivity (66.1 %) were achieved at 220 °C for 6 h under 5 MPa H2 with 5 % Ru. Various catalyst characterization techniques revealed that the acidic characteristics and metal hydrogenation sites of the Ru/S-CCS played a vital role in direct sorbitol production from cellulose. The sorbitol yield and selectivity could be enhanced by the vigorous interactive effect of sulfonic groups and Ru metal sites. The recycling performance of the Ru/S-CCS catalyst was explored under the optimal reaction conditions. Moreover, sorbitol production from glucose, raw CS, and pretreated CS was further investigated. Overall, the results of this study show that the CS biochar used in Ru/S-CCS preparation can be a competitive material for the catalyst preparation in sorbitol production, which may subsequently be used for designing large-scale sugar alcohol production

Pebax/Modified Cellulose Nanofiber Composite Membranes for Highly Enhanced CO₂/CH₄ Separation

This work explored the use of biomass-derived cellulose nanofibers as an additive to enhance the separation performance of Pebax membranes for the removal of CO2 from biogas. Succinate functional groups were modified on the cellulose nanofiber (SCNF) to incorporate more CO2-attracting functional groups before they were added to the polymer matrix. A small addition of SCNF up to 0.5 wt % had no significant impact on the polymer chain packing of Pebax but significantly enhanced the tensile strength and separation performance in both CO2 permeability and CO2/CH4 selectivity. On the other hand, increasing the SCNF addition amount above 1 wt % resulted in a slight alternation of membrane microstructure, i.e., lowering crystallinity, stiffer structure, and reduced tensile strength. At high loading, the CO2 permeability and CO2/CH4 selectivity of the composite membrane were, however, found to decline. This behavior is explained by a greater propensity for interaction among the CO2-attracting functional groups of SCNF and Pebax at elevated SCNF loadings, leading to fewer functional groups available for CO2 sorption. The optimal 0.5% SCNF loading (Pebax/SCNF-0.5) demonstrated a CO2 permeability of 263.8 Barrer and selectivity of 19.9 under 4 bar pressure and an operating temperature of 30 °C. These separation performances increased by 29.69% permeability and 39.04% selectivity compared with those of pure Pebax. These highly impressive results corresponded to the increases in the levels of CO2 dissolution and diffusion via hydrophilic SCNF nanofillers in Pebax. This work could strongly advance the research and development of gas separation technology based on polymeric membranes with the utilization of biobased nanofillers for energy and environmental sectors