Pathai Wongsewasakun*, Pawerasak Phaphungwitayakul, Viboon Changrue, Warakhom Wongchai and Jintanaporn Sangkam
Abstract: Organic rice cultivation areas and organic rice market have been increasing continuously due to a rise in consumers’ demand resulting in better quality of life for producers and consumers. Although there are numerous studies on organic farming involving both of production and marketing, knowledge of energy analysis and greenhouse gas emission in organic rice cultivation process have not been mentioned, especially Riceberry varieties in Thailand. To fill this gap, the energy analysis and greenhouse gas emission of organic Riceberry production in Northern Thailand was evaluated. The organic Riceberry production conducted from July 2020 to January 2021 at Lamphun province, Thailand, was analyzed. The rice variety used in this study was Riceberry. The experimental study was separated into 3 types of green manure (no green manure as control, Crotalaria juncea, and Sesbania rostrata). Each type of green manure was combined with 2 water managements (Continuous flooding; CF, and Alternative wetting and drying; AWD). The result revealed that using Sesbania rostrata in combination with Alternative wetting and drying water management (Sesbania-AWD) was the most suitable method for organic Riceberry production. The main energy consumption was from fuel and machinery (77.48 and 14.58%, respectively), whereas energy use efficiency (EUE), net energy (NE) and specific energy (SE) were 9.40, 108,123.92 MJ/ha and 3.02 MJ/kgpaddy yield, respectively. The main contributor in GHG emission was the methane (CH4) field emission (46.16%), GHG emission from material inputs (28.86%) and nitrous oxide (N2O) field emission (24.98%). Thus, GHG intensity was 0.62 kgCO2-eq/kgpaddy yield.
Keywords: Organic farming, riceberry, Sesbania rostrata, Crotalaria juncea, alternate wetting and drying.
Rachanon Lawanwong, Pornlada Daorattanachai and Navadol Laosiripojana*
Abstract: Furfural is industrially produced from lignocellulosic biomass via hydrolysis/dehydration reactions or C5 sugars (pentoses) via dehydration reaction in aqueous acidic media. Nevertheless, the corrosion problem and side reactions are major problems of this production process. The aim of this work was to study the effects of solvents and catalysts to furfural production from xylose dehydration reaction under biphasic batch reaction system. The study compared two solid acid catalysts (zeolite beta and ZSM-5) and three high boiling point solvents (ethylene glycol, dimethyl sulfoxide and sulfolane). The experimental results revealed that sulfolane and ZSM-5 showed a good performance for furfural production because they provided the highest furfural yield (49.1%) and prevented the occurrence of side reactions. The highest furfural yield (54.8%) from xylose dehydration was achieved at 200 °C with the reaction time of 90 min over ZSM-5 catalyst in sulfolane. For catalyst recycling studies, ZSM-5 catalyst could also be reused up to 4 cycles with a yield of 51%.
Keywords: Xylose dehydration, furfural production, zeolite beta, ZSM-5, sulfolane.
Jittamas Akkarajitsakul, Khatiya Weerasai, Pornlada Daorattanachai* and Navadol Laosiripojana
Abstract: This research focuses on the production of methyl ester sulfonate (MES) from waste coconut fatty acids (WCFAs) via sequential esterification of lauric acid as model compound for WCFAs and the sulfonation of methyl ester (ME). Firstly, lauric acid was converted to ME by esterification with methanol. Then, ME was converted to methyl ester sulfonic acid (MESA) by sulfonation with either methanesulfonic acid (MSA) or sulfuric and followed by bleaching. Next, MESA was neutralized with 20%w/v sodium hydroxide to convert into MES. Finally, MES was synthesized from WCFAs with the optimum condition of esterification and sulfonation that was considered earlier. It was found that esterification of lauric acid with methanol, using molar ratio of lauric acid and methanol at 5:1 provided the highest lauric acid conversion. Sulfonation of ME from lauric acid with 30%v/v MSA at 150 °C for 3 hours provided higher ME conversion than sulfonation with 30%v/v sulfuric acid at 140 °C for 3 hours. Next, esterification of WCFAs by using molar ratio of WCFAs and methanol at 10:1 provided WCFAs conversion around 98.6%. Sulfonation of ME from WCFAs with MSA provided higher ME conversion compared with sulfonation with sulfuric acid at 87.1% and 79.4%. The MES selectivity from sulfonation of ME from WCFAs with MSA and sulfuric was 83.2% and 73.8%. The MES from WCFAs with MSA and sulfuric acid had critical micelle concentration (CMC) at 4.8 and 2.7 mM, surface tension at CMC was 25.9 and 21.7 mN/m, and Krafft point was 10 and 8 °C.
Keywords: Coconut fatty acid, esterification, sulfonation, methanesulfonic acid, methyl ester sulfonate.