W. R. Grace Co.-conn.

Alliedsignal Inc.

Other

Mobil Oil Corporation

Exxonmobil Research and Engineering Company

Exxonmobil Corporation

Lloyd Steven White

Richard Franklin Wormsbecher

Markus Lesemann

Bhupender S Minhas

I-Fan Wang

Dennis G Peiffer

Jeffrey C Trewella

Arthur A Chin

Ronald M Gould

Robert Henry Sedath

William A Feehley

Harold A Kloczewski

Thomas E Sulpizio

Donald R Taylor

Krishna S Menon

Michael Mayers

Terry R Waldron

Bryan M Knickerbocker

A multi-layer membrane structure including a crosslinked polymeric membrane, such as a crosslinked polyvinyl sulfate membrane or a crosslinked copolymer polyvinyl sulfate and polyvinyl alcohol membrane, is provided. The membrane structure is suitable for use in an acid environment, and is suitable for recovering acid from a feed mixture comprising acid, hydrocarbons and water.

Acid tolerant polymeric membrane and process for the recovery of acid using polymeric membranes

A membrane process for the removal of sulfur species from a naphtha feed, in particular, a FCC light cat naphtha, without a substantial loss of olefin yield is disclosed. The process involves contacting a naphtha feed stream with a membrane having sufficient flux and selectivity to separate a sulfur deficient retentate fraction from a sulfur enriched permeate fraction, preferably, under pervaporation conditions. Sulfur deficient retentate fractions are useful directly into the gasoline pool. Sulfur-enriched permeate fractions are rich in sulfur containing aromatic and nonaromatic hydrocarbons and are further treated with conventional sulfur removal technologies, e.g. hydrotreating, to reduce sulfur content. The process of the invention provides high quality naphtha products having a reduced sulfur content and a high content of olefin compounds.

Membrane separation for sulfur reduction

Permselective separation of aromatic hydrocarbons from non-aromatic hydrocarbons in a feed stream is accomplished using improved asymmetric membranes. The preferred membranes are fashioned from a polyimide and conditioned with a lubricating oil. Feed streams containing a mixture of aromatic and non-aromatic hydrocarbons are contacted with the dense active layer side of the polyimide membrane under a pressure and temperature sufficient to selectively permeate the desired aromatic hydrocarbon.

Recovery of aromatic hydrocarbons using lubricating oil conditioned membranes

Improved asymmetric hyperfiltration membranes and their method of preparation and use are disclosed. The membranes are fashioned from polyimides and conditioned with a lubricating oil. Permselective separation of aromatic hydrocarbons from non-aromatic hydrocarbons in a feed stream may be accomplished using the membranes under hyperfiltration conditions.

Polyimide membranes for hyperfiltration recovery of aromatic solvents

A polyimide gas separation membrane can be used to make protective cloth having good water vapor breathability as well as good resistance to permeation by noxious gases and penetration by liquid water.

Barrier membrane for protective clothing

A semicontinuous process for solvent dewaxing a waxy petroleum oil feed stream including the steps of: diluting of the waxy oil feed stream with solvent; feeding cold oil/solvent/wax mixture to a filter to remove the wax and obtain an oil/solvent filtrate stream; contacting the oil/solvent filtrate stream with a selective semipermeable membrane to selectively transfer solvent through the membrane to obtain a solvent-rich permeate; and periodically directing a warm stream of recovered solvent onto the membrane surface to wash the membrane and remove impurities therefrom.

Lubricating oil dewaxing with membrane separation

An improved asymmetric membrane fashioned from a polyimide for the liquid separation of solvents from lube oil. The membrane is based on a fully imidized polymer based on 5(6)-amino-1-(4'-aminophenyl)-1,3,3-trimethylindane polymer and benzophenone tetracarboxylic dianhydride.

Polymide membrane for separation of solvents from lube oil

An improved asymmetric membrane fashioned from a polyimide for the liquid separation of solvents from lube oil. The membrane is based on a fully imidized polymer based on 5(6)-amino-1-(4'-aminophenyl)-1,3-trimethylindane polymer and benzophenone tetracarboxylic dianhydride.

Polyimide membrane for separation of solvents from lube oil

The instant invention is a membrane useful for separating organic matter such as proteins from aqueous solutions which resists fouling and maintains a high flux during separation. The membrane is prepared by either drying a polysulfone composite membrane, or first treating a polysulfone composite membrane with aqueous methanol and then drying it. The membrane is then exposed to elemental fluorine in an inert gas in the substantial absence of oxygen at a temperature in the range of about -45.degree. to 70.degree. C. After fluorine treatment, the membrane is exposed to air. The fluorine content in the treatment mixture may be from 0.0125 to about 10 volume percent, preferably 0.025 to 2 volume percent. The fluorine treatment does not significantly alter the membrane pore size.

Reduction of membrane fouling by surface fluorination

An absorbent article comprising a cellulosic membrane about 5 to 50 .mu.m thick prepared by casting a film from solution of a cellulose derivative in a suitable solution and these formed into a packet which encapsulates an osmotic promoter, particularly sodium chloride, sugar or other suitable compound, preferably having a molecular weight below about 500. The packet is capable of taking up at least 0.001 g/cm.sup.2 /min of water and retaining it against an external pressure of at least 0.689 kPa.

Growing community of inventors

Columbia, MD, United States of America

Lloyd Steven White