The microfiltration process of solvent naphtha 200 containing impurities was studied using multichannel ceramic membranes with pore diameters of 0.5 and 0.8 mu m. The effects of operating time, transmembrane pressure, cross-flow velocity, and temperature on permeate flux and rejection were investigated. The scanning electron microscop and energy dispersive spectrometry were conducted for the clean and fouled membranes. Effect of backflushing on permeate flux was also studied. Results show that it is possible to recover over 94% of the original flux by a program of backflushing. A concentration process was carried out and furthermore, various membrane resistances were calculated. Finally, commercial detergent, HNO3, and NaOH + NaClO cleaning stages were used for the 0.5-mu m membrane.