2.Manufacturing technique of wax microcrystalline: with crude oil vacuum residua fractions as material, it is made from propane taking off asphaltum, furfural refining, ketone benzene taking off oil, and argil refining.
3.Type-Ⅱ clay, which includes argillanceous rocks, attapulgite, rectorite, illite, and argil, etc. , has an equilibrium removal efficiency of 50%~80%, a t 50 of less than 2.5 h, and a t 80 of more than 5 h.