采用地沟油水解副产物甘油和多聚甲醛制备了1，3-二氧杂环戊-4-酸（DIC）中间体，再使用DIC与邻苯二胺及其衍生物进行酰胺化-环化反应合成了三种新的目标产物2-（1'，3'-二氧五环-4'-基）苯并咪唑（OBCI）、1-甲基-2-（1'，3'-二氧五环-4'-基）苯并咪唑（MBCI）和1-苯基-2-（1'，3'-二氧五环-4'-基）苯并咪唑（PBCI）；采用浸泡试验、电化学试验和扫描电子显微镜（SEM）等研究了这三种化合物在5%（质量分数）HCl溶液中对Q235钢的缓蚀作用。结果表明：三种缓蚀剂在5% HCl溶液中对Q235钢都具有良好的缓蚀效果，缓蚀率随着缓蚀剂含量的增加而增大，当缓蚀剂质量浓度为100 mg/L时，失重法测得的最大缓蚀率均超过97%；三种缓蚀剂在Q235钢表面的吸附规律均符合Langmiur吸附等温式，吸附过程为自发进行的化学吸附。

The intermediate of 1,3-dioxolane-4-carboxylic acid (DIC) was prepared using glycerin from by-product of illegal cooking oil hydrolysis and polyformaldehyde as raw materials. Three target products, 2-(1',3'-dioxolan-4-yl) benzimidazole (OBCI),1-methyl-2-(1',3'-dioxolan-4-yl) benzimidazole (MBCI) and 1-phenyl-2- (1',3'-dioxolan-4-yl) benzimidazole (PBCI) were synthesized by amide-cyclization reaction between DIC and o-phenylenediamine and its derivatives. The inhibition performance of the three compounds to Q235 steel in 5% (mass fraction) HCl solution was studied by immersion testing, electrochemical testing and scanning electron microscopy (SEM). The results show that the corrosion inhibitors had good corrosion inhibition to Q235 steel in 5% HCl solution, and the inhibition efficiency increased with the increase of inhibitor concentration. When the mass concentration of corrosion inhibitors was 100 mg/L, the maximum corrosion rates measured by weitht-loss method were more than 97%. The adsorption of three inhibitors on the surface of Q235 steel followed the Langmuir adsorption isotherm,and the adsorption process was spontaneous chemisorption.