A porous support includes a base body, a supporting layer, and a topmost layer. The supporting layer is disposed between the base body and the topmost layer, and makes contact with the topmost layer. A ratio of a porosity of the topmost layer to a porosity of the supporting layer is greater than or equal to 1.08. A ratio of a thickness of the topmost layer to a thickness of the supporting layer is less than or equal to 0.9.

The invention is an improved method of making a carbon molecular sieve (CMS) membrane in which a precursor polymer is pyrolyzed to form a carbon molecular sieve membrane that is then exposed to a conditioning atmosphere comprised of a target permeate gas molecule such as ethylene when the membrane is desired to separate it from a light hydrocarbon gas stream. The exposure to the ethylene desirably occurs prior to the CMS permeance and selectivity combination substantially changing (e.g., within 5 days) of cooling from the pyrolyzing temperature. The CMS membranes have shown an improved combination of selectivity and permeance as well as stability and are useful to separate gases in gas streams such methane from natural gas, oxygen from air and ethylene or propylene from light hydrocarbon streams.

Provided is a method for producing a separation membrane including a silicalite membrane without using NaOH or the like that causes an increase in cost with respect to equipment, facilities, and process time. The method for producing a separation membrane is a method for producing a separation membrane including a porous support and a silicalite membrane that is formed on the support and has an MFI-type zeolite crystal structure, and is characterized in that the method includes a step of producing a seed crystal, a step of attaching the seed crystal onto the porous support, a step of producing a membrane synthesis raw material composition containing SiO.sub.2, an organic template, and H.sub.2O, and a step of immersing the porous support having the seed crystal attached thereto in the membrane synthesis raw material composition and performing hydrothermal synthesis, and the composition ratio of the membrane synthesis raw material composition is as follows: SiO.sub.2:organic template:H.sub.2O=1:(0.05 to 0.15):(50 to 120).

The disclosure relates to a method for fermentation integrated with separation and purification of acetone, butanol, and ethanol (ABE) or butanol alone, comprising the following steps: 1) obtaining ABE by fermentation using an acetone-butanol-producing bacterium or obtaining butanol using a butanol-producing bacterium; 2) using a “vapor-stripping-vapor-permeation” method (briefly VSVP) for online separation and purification of ABE or purifying butanol from the fermentation broth; wherein the VSVP method comprises the following steps: introducing a gas bubble into the fermentation broth comprising active cells for fermentation to vaporize ABE or Butanol; subjecting the gas along with the vaporized ABE or Butanol to a membrane separation unit to pass through the membrane; recovering ABE or Butanol, or subjecting ABE or Butanol to a next separation device. By using the disclosed method, production, separation, and purification efficiency of ABE or butanol are improved with saved energy consumption and without increasing equipment investment.

A dehydration method is a dehydration method for selectively separating water from a mixture that contains water, and the method includes a step of supplying the mixture to a supply side space of a zeolite membrane having an ERI structure, and a step of making a pressure difference between the supply side space and a permeation side space of the zeolite membrane having an ERI structure.

A porous support-zeolite membrane composite comprising an inorganic porous support and a zeolite membrane provided on, wherein the zeolite membrane contains a zeolite having a microporous structure of 8-membered oxygen ring or less, and a molar ratio of SiO.sub.2/Al.sub.2O.sub.3 in the zeolite membrane surface is larger by at least 20 than a molar ratio of SiO.sub.2/Al.sub.2O.sub.3 in the zeolite membrane itself, or a water adsorption of the porous support-zeolite membrane composite at a relative pressure of 0.8, as determined from a water vapor adsorption isotherm of the porous support-zeolite membrane composite, is at least 82% of a water adsorption of the porous support-zeolite membrane composite under the same condition as above after one-week immersion of the porous support-zeolite membrane composite in an aqueous 90 mass % acetic acid solution at room temperature.

A carbonized PVDC copolymer useful for the separation of an olefin from its corresponding paraffin may be made by heating a polyvinylidene chloride copolymer film or hollow fiber having a thickness of 1 micrometer to 20 micrometers to a pretreatment temperature of 100° C. to 180° C. to form a pretreated polyvinylidene chloride copolymer film and then heating the pretreated polyvinylidene chloride copolymer film to a maximum pyrolysis temperature from 350° C. to 750° C. A process for separating an olefin from its corresponding paraffin in a gas mixture is comprised of flowing the gas mixture through the aforementioned carbonized polyvinylidene chloride (PVDC) copolymer to produce a permeate first stream having an increased concentration of the olefin and a second retentate stream having an increased concentration of its corresponding paraffin.

A process for separating hydrogen from a gas mixture having hydrogen and a larger gas molecule is comprised of flowing the gas mixture through a carbonized polyvinylidene chloride (PVDC) copolymer membrane having a hydrogen permeance in combination with a hydrogen/methane selectivity, wherein the combination of hydrogen permeance and hydrogen/methane selectivity is (i) at least 30 GPU hydrogen permeance and at least 200 hydrogen/methane selectivity or (ii) at least 10 GPU hydrogen permeance and at least 700 hydrogen/methane selectivity. The carbonized PVDC copolymer may be made by heating and restraining a polyvinylidene chloride copolymer film or hollow fiber having a thickness of 1 micrometer to 250 micrometers to a pretreatment temperature of 100° C. to 180° C. to form a pretreated polyvinylidene chloride copolymer film and then heating and restraining the pretreated polyvinylidene chloride copolymer film to a maximum pyrolysis temperature from 350° C. to 750° C.

The present invention relates to a process for the calcination of a zeolitic material, wherein said process comprises the steps of (i) providing a zeolitic material comprising YO.sub.2 and optionally further comprising X.sub.2O.sub.3 in its framework structure in the form of a powder and/or of a suspension of the zeolitic material in a liquid, wherein Y stands for a tetravalent element and X stands for a trivalent element; (ii) atomization of the powder and/or of the suspension of the zeolitic material provided in (i) in a gas stream for obtaining an aerosol; (iii) calcination of the aerosol obtained in (ii) for obtaining a calcined powder; as well as to a zeolitic material obtainable and/or obtained according the inventive process, and to its use as a molecular sieve, as an adsorbent, for ion-exchange, as a catalyst, and/or as a catalyst support.

The present invention relates to a process for producing a porous support-zeolite membrane composite, which comprises forming a CHA type zeolite membrane on a porous support by a hydrothermal synthesis in the presence of seed crystals, wherein an FAU type zeolite is used as the seed crystals.