Abstract: A process for refining vegetable oil from a miscella obtained by extraction of vegetable seeds with an organic solvent, which comprises permeating the miscella through an ultrafilter made of an inorganic microporous membrane having a pore size of from 30 to 100 .ANG. in a state heated at a temperature of from 50.degree. to 120.degree. C. to remove impurities contained in the miscella.

Abstract: A process for manufacturing a ceramic filter having a given pore size required as a filter membrane and also having superior alkali resistance and acid resistance. The filter of the present invention is produced by preparing an aggregate comprising alumina coarse particles and a sintering aid comprising alumina-zirconia mixed particles containing not more than 90 wt. % of alumina, blending said alumina coarse particles and alumina-zirconia mixed particles so as for alumina to be in an amount of from 80 to 99 wt. % based on the total weight of the starting materials, forming the blended starting materials to have a desired shape, and firing the formed product.