Studies on effect of various solvents on extraction of cashew nut shell liquid(CNSL) and isolation of major phenolic constituents from extracted CNSL

Cashew nut shell liquid (CNSL) and its derivatives are widely used in polymer-based industries, synthesis of chemicals and intermediates including bactericides, insecticides and surface active agents. Commercially available CNSL mainly contains phenolic constituents such as anacardic acid, cardanol and cardol. Cardanol contains polymerizable side chain and phenolic group. Cardanol and its various derivatives have found numerous industrial applications. In the present study, extraction of CNSL from cashew nut shell was performed using soxhlet extraction method in presence of various polar and non polar solvents. Among all the solvents acetone gives maximum amount of CNSL. From the extracted CNSL, anacardic acid was selectively isolated and acid free CNSL was treated with liquor ammonia to separate the cardanol and cardol in stepwise manner. They were all characterized using quantitative analysis by HPLC. Technical CNSL provided higher content of cardanol compared to natural CNSL.