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Microwave assisted synthesis of 5-hydroxymethylfurfural (HMF) using hydrolysate produced from dilute acid hydrolysis of bamboo with low transition temperature mixture (LTTM) as a green solvent was performed. Bamboo was a fast-growing plant with high cellulose content in the biomass, which made it suitable as the raw material for HMF production. LTTM was produced from hydrogen bond acceptor and donor, which in this study were choline chloride and malic acid, respectively. Microwave irradiation was used as it is faster and energy saving than conventional heating methods. A two-factors three-levels full factorial design with temperature and reaction time as the manipulating variables was employed and a linear model was constructed with R2 of 0.9640 and p-value of 0.0115, indicating good reliability and significant. ANOVA analysis informed that only the temperature was significant, where the optimum point was 120 °C and 10 min with HMF yield of 10.7951 %. A follow up study was conducted at 140 °C and 5 min and had found that the system established an equilibrium of temperature at 120 °C between the heat loss by evaporation of water and heat gained by microwave irradiation. The shorter reaction time also resulted in higher HMF yield of 10.9410 %, possibly due to lower degree of unwanted side reaction (i.e., rehydration of HMF into levulinic acid). This study shows that it is possible to directly utilise the hydrolysate of bamboo without further separation of glucose in conversion into HMF, a valuable green and sustainable platform chemical. [ABSTRACT FROM AUTHOR]

Emission of greenhouse gases is currently recognized as one of the most significant problems confronting societies all over the world. Human activities, such as the consumption of fossil fuels for the generation of heat and electricity, as well as other industrial operations and transportation, are the primary sources of greenhouse gas emissions. The implementation of adsorption technology for the capture of carbon are widely used to lower the greenhouse gas emissions mainly carbon dioxide (CO2). However, there are still insufficient research has been done on the performance of Meranti sawdust as a low-cost carbon for CO2 capture, particularly by using a greener activation agent. A mechanochemical activation method using potassium carbonate (K2CO3) is highlighted in this study, where the approach is simpler and more environmentally friendly. By using the Taguchi L9 orthogonal array, several variables (i.e., temperature, impregnation ratio, duration, N2 flow rate) have been investigated to determine the optimal operating conditions to obtain high yield activated carbon. From the findings, it is shown that the optimal conditions for the activated carbon production is at 700 °C, impregnation ratio of 3:1, carbonization time of 60 min, and N2 flow of 900 mL/min, with corresponding activated carbon yield is approximately 41 % and CO2 adsorption capacity of 2.8 mmol/g. The carbon materials are to be evaluated in terms of elemental composition, surface functionalities and morphologies, as well as textural characteristics. Overall, wood waste conversion to activated carbon aligns with SDG 9, SDG 12, as well as SDG 13. [ABSTRACT FROM AUTHOR]