A STUDY OF CARBONACEOUS GEL FROM PITCH

Aqua mesophase pitch (AMP) was prepared through oxidation of coal tar pitch with mixtures of concentrated sulfuric acid and nitric acid. The formation conditions of carbonaceous gel in aqueous solution from AMP were discussed. The results indicate that the oxidation temperature, AMP concentration, pH value of carbonaceous sol and amount of added ethanol influence on the carbonaceous gelation. In alkaline media, the carbonaceous gelation time decreases with decreasing of oxidation temperature and increasing of the concentration of AMP and pH value. In acidic media, the carbonaceous gel can be formed through flocculation of AMP in aqueous alkaline solution by adding aqueous HCl solution as flocculent. Carbonaceous gel can be formed in a wide range of pH values.