The New Jersey Institute of Technology's
Electronic Theses & Dissertations Project

Title:	Removal of gasoline-based hydrocarbons by vapor permeation membranes
Author:	Bagavandoss, Shivashanker
View Online:	njit-etd1996-042 (xi, 84 pages ~ 2.7 MB pdf)
Department:	Department of Chemical Engineering, Chemistry and Environmental Science
Degree:	Master of Science
Program:	Chemical Engineering
Document Type:	Thesis
Advisory Committee:	Sirkar, Kamalesh K. (Committee chair) Perna, Angelo J. (Committee member) Luo, Robert G. (Committee member)
Date:	1996-10
Keywords:	Membrane separation. Volatile organic compounds.
Availability:	Unrestricted
Abstract:	Removal and recovery of evaporated lighter gasoline fractions can be effectively implemented by selectively permeating the hydrocarbons (HCs) and other volatile organic compounds (VOCs) from the vented air streams through nonporous hydrophobic polymeric membranes subjected to vacuum on the permeate side and then condensing these organics from the permeate. Such a vapor permeation process employing spiral-wound membranes has already been commercialized for VOCs. In this study, attention has been focused on removal of hydrocarbons from nitrogen flowing through the bore of microporous hydrophobic hollow fibers with a specially engineered nonporous silicone coating on the outside surface with a view to reducing the HC concentration in treated gas stream from 17% to the lowest desirable level. Membrane modules containing such hollow fibers possess 7-10 times more surface area per unit volume, have higher selectivities to hydrocarbons and lowered air flux due to the flow configuration, pore condensation and the membrane type. Studies with an inert liquid immobilized in the substrate pores of the membranes (ILM) have shown very high selectivities compared to the composite membrane. A mathematical model has been developed to explain the permeation-separation behavior of the hydrocarbons and the VOCs as well. A novel aspect of the model is the effort made to illustrate and explain the difference between the two modes of introduction of the feed viz. shell-side and tube-side.