Study on the New Method of Preparing Pyrogallic Acid from Gallic Acid
pyrogallic acid was prepared through decarboxylation of gallic acid catalyzed by a nitrogen-containing organic compound with high boiling point. Compared to traditional methods, this method has many advantages including low decarboxylation temperature, fast reaction speed, simple operation process, inexpensive catalyst, good catalytic effect, low alkalescence, less by-products, catalysts with a high boiling point to ensure product quality, and high-purity products obtained without any post processing. Effects of catalyst types and dosage, reaction temperature, reaction time, sublimation temperature and time on the yield of pyrogallic acid were investigated. It was shown from the test results that the influence of catalyst types and their dosage on pyrogallic acid yield and quality was most significant, and the suitable decarboxylation conditions were determined as follows: a new catalyst for decarboxylation of gallic acid was screened out, and the amount of catalyst was 8％ based on the weight of anhydrous gallic acid, reaction temperature 150℃, reaction time 1.5 h, sublimation temperature 160℃, sublimation time 1.5 h. Yield of obtained product was 96.9％, purity of obtained product was 99.5％. The structure of pyrogallic acid was identified by FT-IR and HPLC-MS.
gallic acid pyrogallic acid nitrogen-containing catalyst decarboxylation
Yang YANG Bing LIU Wang-wei AO Wen GU Shi-fa WANG
College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, PR China
国际会议
南京
英文
912-918
2010-10-22（万方平台首次上网日期，不代表论文的发表时间）