Process optimization with acid functionalised activated carbon derived from corncob for production of 4-hydroxymethyl-2,2-dimethyl-1,3-dioxolane and 5-hydroxy-2,2-dimethyl-1,3-dioxane

In this article, a two-step activated carbon preparation technique from corncob has been elucidated. The derived catalysts AAC-CC has been characterized using various techniques for the determination of their structural properties and compared with AC-CC, already reported with another article. The conjugated boat structure of AAC-CC resulted in a very high surface area (779.8 m2/g) and high pore volume (0.428 cc/g). This unveils the suitability of AAC-CC as better among the two catalytic pathways for solketal production. The activated carbons so prepared have been used for the valorization of glycerol to produce 2,2-Dimethyl-1,3-dioxolane-4-methanol (solketal), oxygenated additives to fuel. The face-centered composite design (FCCD) of RSM was applied for the optimization of the reaction parameters for the ketalisation reaction using AAC-CC as a catalyst. From the optimized results, the acidic catalyst AAC-CC resulted in a glycerol conversion, i.e. 80.3% under the actual laboratory experiment. Moreover, the catalyst could be reused for three consecutive batch reactions without (< 5%) much reduction of activity and no distinctive structural deformity.

USE OF DIESEL MIXED WITH ETHANOL AND ETHYL ACETATE FOR ALTERNATIVE FUEL IN A HIGH-SPEED DIESEL ENGINE

Particulate matters especially particles with less than 2.5 micrometers (PM2.5) are the main cause of severe air pollution problem in Thailand that lead to the mortality risk in cardiovascular disease. Exhaust gas emissions specifically carbon monoxide and black smoke from diesel engines are the essential sources in generating significant amounts of PM2.5. Improving diesel properties by mixing oxygenated additives is one of the alternatives in reducing this pollutant. The main objective of this research is to investigate the performance and emission of a high-speed diesel engine at 3,000 rpm and different loads operated with diesel mixed with 5 to 20% ethanol and 5% ethyl acetate. The results of engine test at 80% load using diesel mixed with 5% of ethanol and ethyl acetate showed a few decreases in fuel properties and engine performance compared with diesel. The release of black smoke was also decreased to 14%. Increasing the mixture of ethanol to more than 5% has led to the decrease in engine performance continuously. The diesel mixed with ethanol at 20% and ethyl acetate at 5% has reduced the carbon monoxide and black smoke to 0.012%vol and 31.53% respectively and accrued the carbon dioxide at 1.25%vol. This is because the diesel mixed with ethanol and ethyl acetate increased the oxygen level to perform complete combustion as compared with diesel. However, the temperature of these exhaust gases was raised to 55oC