The effects of experimental variables such as temperature, time, type of solvent and nature of the clay-supported hydrogen peroxide on the degree of epoxidation of cashew nut shell liquid (CNSL) and cashew nut oil (CNO) were investigated by iodine value measurements. Results show that the acid treatment of the bentonite clay improved its support characteristics by achieving some increase in surface area and optimum treatment condition was found to be 10g bentonite clay treated with 30cm3 sulphuric acid for 6 hours. It was found that higher epoxidation was achieved with treated clay-supported hydrogen peroxide, elevated temperature and polar (1, 4dioxane) solvent than the corresponding untreated clay-supported reagent, at room temperature and using a non-polar (toluene)solvent, respectively.
Optimum epoxidation condition was determined epoxidation time of 4 hours using treated clay-supported hydrogen peroxide in 1, 4-dioxane and at elevated temperature of 50°C and at the lowest iodine values of 122.14 (D(F)), 112.62 (D(G)), 100.25 (D(H)), 98.98 (D(I)), 93.91 (D(J)), and 63.13 (D(F)), 60.91 (D(G)), 59.32 (D(H)), 56.15 D(I)), 54.57 (D(J)), for cashew nut shell liquid and cashew nut oil respectively.
Keywords: epoxidation, clay-supported hydrogen peroxide, cashew nut shell liquid (CNSL), cashew nut oil (CNO).
Global Journal of Pure and Applied Sciences Vol. 11(4) 2005: 505-510