We describe preparation of a ZSM-5 zeolite membrane, used for separation of benzothiophene and 3-methylthiophene from their n-hexane solutions. We have established the effect of the feed flow rate, the membrane operating time, filtration pressure, and concentration of sulfur compounds in the feed on the membrane flux. As the membrane flux increases, the desulfurization ratio gradually decreases. Filtration was carried out in two modes: cross-flow filtration and end-filtration. The separation factor and the desulfurization ratio were higher in cross-flow filtration.