Microwave (MW) assisted Esterification of Benzoic Acid (BA) offers the advantage of transformation of energy and heating throughout the volume efficiently in a shorter period and eliminates the use of excess solvent, during the course of reaction. The present study aims to assess the conversion and selectivity for the production of methyl benzoate compounds by esterification of benzoic acid using microwave irradiation. Effects of operating parameters such as reaction time, feed composition, microwave energy and reaction temperature were systematically investigated for the esterification of BA. Advantages like reduction in reaction time, minimization of waste acid production, and enhanced yield and selectivity for the desired products were important
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Fig:3% Selectivity of methyl benzoate (MB),Methyl oxobenzoate(MOB) and others with respect to time in minutes using Microwave Irradiation ,Reaction temperature :70 ᵒC,Feed ratio,BA:M:Hβ(Benzoic acid:Methanol:Zeolite Hβ)::1:3:1. Fig:4% Selectivity of methyl benzoate (MB) with respect to time and temperature using MW 300 watt,feed ratio,BA:M:Hβ(Benzoic acid:Methanol:Zeolite Hβ)::1:3:1.
With the use of solid acid catalyst (Hβ),same reaction is performed at temperture 70°C with the feed ratio Benzoic acid: Methanol: Hβ:: SA:M: β::1:3:1.
As the activity of zeolite enhances with temperature, so at 70°C, maximum conversion(83%) of BA and selectivity for MB(50%) are obtained. Again here with increase in temperature MB is produced with 64 % selectivity. In fig.4 effect of time shows that with Hβ 70 °C and with Hβ 80°C temperature gave the maximum selectivity to the desired product MB within the reaction time 15 min only.If the time of reaction increases, the selectivity remains constant.Increase in temperature decreases the selectivty of MB decreases as the boiling point of methanol is
Fig:3% Selectivity of methyl benzoate (MB),Methyl oxobenzoate(MOB) and others with respect to time in minutes using Microwave Irradiation ,Reaction temperature :70 ᵒC,Feed ratio,BA:M:Hβ(Benzoic acid:Methanol:Zeolite Hβ)::1:3:1. Fig:4% Selectivity of methyl benzoate (MB) with respect to time and temperature using MW 300 watt,feed ratio,BA:M:Hβ(Benzoic acid:Methanol:Zeolite Hβ)::1:3:1.
With the use of solid acid catalyst (Hβ),same reaction is performed at temperture 70°C with the feed ratio Benzoic acid: Methanol: Hβ:: SA:M: β::1:3:1.
As the activity of zeolite enhances with temperature, so at 70°C, maximum conversion(83%) of BA and selectivity for MB(50%) are obtained. Again here with increase in temperature MB is produced with 64 % selectivity. In fig.4 effect of time shows that with Hβ 70 °C and with Hβ 80°C temperature gave the maximum selectivity to the desired product MB within the reaction time 15 min only.If the time of reaction increases, the selectivity remains constant.Increase in temperature decreases the selectivty of MB decreases as the boiling point of methanol is