Abstract: This paper has carried out the optimized design with the orthogonal testing method on the strong sulfuric acid catalysis and the microwave radiation synthesis of methyl salicylate. This experiment used L25 (54) orthogonal table to complete the study of the strong sulfuric acid catalysis synthesis of methyl salicylate. It investigated the yield of ester by using different proportion of salicylic acid and methanol, different mix blend velocity, different quantity of sulfuric acid volume and different reaction time. The results enunciate that the most suitable reaction condition is that: the proportion of salicylic acid and methanol is 1:5, the mix blend velocity is 200r/min, the sulfuric acid volume is 11 mL, reaction time is 6 hours, and the ester yield is 75.0%. Then we used L16 (44) orthogonal table to complete the study of the microwave radiation synthesis of methyl salicylate. It investigated the yield of ester by using different proportion of salicylic acid and methanol, different radiation power, different quantity of sulfuric acid volume and different reaction time. The result enunciate that the most suitable reaction condition is that: the proportion of salicylic acid and methanol is 1:7, the powder is 195W, the sulfuric acid volume is 9 mL, and reaction time is 20 min, and the ester yield is 82.5%. By comparison, we can draw the conclusion that when microwave radiation technology was used in esterification with the advangtages of short reaction times and high yields.
Key words: Methyl salicylate; Microwave radiation synthesis; Catalytic esterification; Orthogonal design
