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Esterification of acetic acid with methanol to produce methyl acetate in an isothermal stirred batch reactor has been studied. Sulfuric acid was used as a liquid catalyst, and Indion-180, Indion-190 and Amberlyst-16wet ion exchange resins were used as solid catalysts. The feed mole ratio was varied from 1 : 1 to 1 : 4. The reaction temperatures were varied from 305.15 to 333.15 K for sulfuric acid as catalyst and 323.15 to 353.15 K for the solid catalysts. The catalyst concentrations were used in the range of 1% to 5%, for the sulfuric acid catalyst, and 0.01 to 0.05 g/cc, for the solid catalysts. The effect of temperature, catalyst concentration, agitation speed, size of catalyst particle and reactant concentration on the acetic acid conversion was investigated. A second-order kinetic rate equation was proposed to fit the experimental data. For both forward and backward reactions, the activation energies were estimated from Arrhenius plots. The reaction rate increased with catalyst concentration and temperature for both the liquid and solid catalysts. The acetic acid conversion was found to increase with increases in acetic acid to methanol ratio in the feed. The developed kinetic rate equation was used for the simulation of reactive distillation process, in our laboratory column.

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Catalytic esterification of acetic acid with methanol to produce methyl acetate in a stirred batch reactor was investigated in the presence of Amberlyst 16, Indion 180 and Amberlyst 36 catalysts. Amberlyst 36 was found to be an effective solid catalyst for this reaction compared to the other solid catalysts. The reaction was performed in the temperature range of 323.15–353.15 K and the catalyst loading in the range of 0.01–0.05 g cm−3. The initial reactant feed molar ratios of acetic acid to methanol were varied from 1:1 to 1:4. The influence of different parameters like temperature, catalyst loading, magnetic stirrer speed and average catalyst particle sizes on the conversion kinetics of acetic acid has been investigated. The maximum conversion of acetic acid was increased on increasing the feed molar ratio. From the experimental results, it was observed that the reaction is kinetically controlled rather than controlled by internal and external mass transfer. The experimental data were correlated with the pseudo homogeneous (PH), Eley–Rideal (ER) and Langmuir–Hinshelwood (LH) models. The activity coefficients were calculated using UNIQUAC model to account for the non-ideal behaviour of the components. Of the different kinetic models; the LH, surface rate-determining model, fitted best with the experimental data.

Biomass fuels come from many varieties of sources resulting in a wide range of sizes, physical and chemical properties. Among the technologies that can be used for biomass combustion, fluidized beds are emerging as the best due to their flexibility and high efficiency. The emissions from Fluidized Bed Combustor (FBC) are dependent on a number of operating conditions (temperature, excess air, fuel feed rate, etc) and fuel particle size. In the present work the effect of fuel particle size on emissions and over all combustion efficiency of groundnut in the fluidized bed combustor has been discussed. The river sand was used for ensuring sustainable fuel ignition and combustion in FBC. The Fluidized bed was operated at constant feed rate 25 kg/h of groundnut shells for various excess air factors (20-100%) and for the different fuel particle sizes. The effect of excess air factor and fuel particle size on the concentration profiles of the major gaseous emissions (CO and CO2), combustion efficiency, as well as the temperature profiles along the combustor height, was investigated. Based on CO emission and unburned carbon content in fly ash, the combustion efficiency of the Fluidized bed combustor was calculated for the ground nut shells fired under different operating conditions. The maximum combustion efficiency of the groundnut shells is found to be 89.5% for lower particle size (0.273mm)