关键词: 二氧化碳, 活性白土, 二聚酸

Abstract: In the industrial process of oleic acid polymerization，activated clay was used as catalyst. The used clay was generally treated as waste to be buried because of difficult recovery，not only polluting the environment but also causing a waste of raw materials and products. In order to reduce the amount of activated clay，a new technology was studied under carbon dioxide circumstance. The effects of reaction temperature，pressure，mass fraction of clay，mass fraction of Li2CO3，mass fraction of H2O and reaction time on the synthesis process of dimer acid were discussed. The yield of dimer acid was considered a primary evaluating index. Reaction temperature could be elevated from 240 ℃ to 250 ℃when the reaction occurred under 0.5MPa CO2. The new process decreased the amount of activated clay by 25% at the same yield of dimer acid compared to the existing process. Adding carbon dioxide has a good inhibition on decarboxylation，this process decreased the amount of activated clay and made possible oleic acid polymerization at a higher temperatures.

Key words: carbon dioxide, activated clay, dimer acid