每年出版 4 期
ISSN 打印: 2572-9896
ISSN 在线: 2572-990X
Indexed in
SYNTHESIS OF 3-METHOXYCATECHOL FROM PYROGALLOL AND DIMETHYL CARBONATE IN LIQUID PHASE SLURRY REACTOR
摘要
Selective mono O-methylation of pyrogallol (trihydroxy benzene) is traditionally carried out with a polluting homogenous base catalyst and various alkali salts. A heterogeneous catalytic system was developed to achieve the same in a liquid phase slurry reactor. Calcined hydrotalcite was synthesized by different synthesis routes, and its activity was studied for selective mono O-methylation of pyrogallol using dimethyl carbonate as a methylating agent. The reaction was optimized by studying different reaction parameters to illustrate the reaction kinetics. The reaction at optimum conditions, i.e., catalyst concentration of 0.035 g/cm3, 180°C, 1400 rpm, and mole ratio of pyrogallol to dimethyl carbonate (DMC) as 1:5 gave 52% conversion of pyrogallol with 89% selectivity toward 3-methoxy catechol. The catalyst is reusable over three cycles. The activation energy for the reaction was calculated as 8.81 kcal/mol. Use of DMC as the methylating agent adds the green content to the current work.