Synthesis of sodium cardanol sulfonate from cashew nut shell liquid

Abstract

The synthesis of sodium cardanol sulfonate from cashew nut shell liquid was carried out by sulfonation using chlorosulfonic acid. This was them followed by neutralization with sodium bicarbonate to give cardanol sulfonate in 61.34% by mole. Varying the reaction time and reaction temperature carried out the sulfonation. The optimized condition for sulfonation reaction was carried out at 0°C for the first 2 hours and then at 20°C for 3 hours, while the neutralization was performed at room thmperature for 6 hours. Hydrogenation was carried out by treating the cardanol with hydrogen at 250 psi in the presence of 10% palladium on actrvated charcoal using an agitation rate of 600 rpm at 200°C for 8 hours to give hydrogenated cardanol in 100% w/w. The hydrogenated cardanol was then used for sulfonation and neutralization under the same conditions to give hydrogebated cardanol sykfibate in 71% by mole. The synthesized product is a cleaning agent known as sodium cardanol sulfonate. The physical properties of sodium sulfonate were compared with those of dodecylbenzene sulfonate. The result of this comparison showed that the surface tension decreased with increasing detergent concentration. C.M.C. of catdanol sulfonate and hydrogenated cardanol sulfonate were 0.0936 and 0.0465 mole/I, respectively. In daaition, the % detergency of cardanol sulfonate and hydrogenated cardanol sulfonate were 87.81% and 94.09%, respectively.