The method of the present invention for separating pyrogens includes passing a pyrogen-containing liquid through a zirconium oxide membrane on a ceramic support. The membrane on ceramic support preferably includes a porous sintered zirconium oxide membrane on alpha-alumina support.

Pyrogens separations by ceramic ultrafiltration

A multilayer inorganic porous membrane consisting of a monolayer or multilayer porous support having at least one surface integrally formed thereon with a porous thin layer having an average pore size less than that of the porous support, wherein a maximum pore size in the support surface is defined to be from 1 to 250 times an average pore size of the thin layer The multilayer porous membrane is superior in preventing the occurrence of pin holes and cracks therein thereby enhancing precision of the filtration and separation

Inorganic porous membrane

A porous inorganic membrane for use with a membrane device having a porous support, the membrane including refractory particles bound to each other and to the support by a thermally reactive inorganic binder which reacts at a temperature below that at which the refractory particles react. Further, a method of forming a porous inorganic membrane on a support by applying a coating of a mixture of refractory particles and a thermally reactive inorganic binder to the support. The inorganic binder reacts at a first temperature lower than a second temperature at which the refractory particles sinter. The method further includes firing the support to a firing temperature at least as high as the first temperature and less than the second temperature to react the inorganic binder, and cooling the support to form the porous membrane.

Method of forming a porous inorganic membrane on a porous support using a reactive inorganic binder

A composite membrane is disclosed which operates as a filter for liquids, solids and gases and combinations thereof, having high permeability for the filtrate, e.g., nitrogen passing therethrough, and high selectivity for matter retained thereby, e.g., volatile organic compounds, so that the N 2 /VOC selectivity is at least about 50/1 or greater; prepared by a low pressure chemical vapor deposition process comprising: (a) providing as a first component thereof, a mesoporous membrane substrate having pore diameters greater than about 20 Å; (b) contacting surfaces, including pore surfaces, of the membrane with at least two reactant gas streams in an opposing reactant geometry, wherein the smallest reactant gas molecule has a kinetic diameter intermediate in size between that of the matter retained by said filter and the filtrate passing therethrough; the reactant gases are capable upon reaction of depositing thereon as a second component thereof, a reaction product which by coating the surfaces, including pore surfaces of said mesoporous substrate, substantially reduces the pore diameters thereof, resulting in a substantially uniform microporous film having pore diameters in the range of from about 4 Å to about 8 Å; the reaction product comprises predominantly silicon oxide, --Si--O--, and may optionally include for the purpose of optimizing the stress, and other mechanical, chemical and thermal properties of said film, minor amounts of one or more members, in any combination thereof, selected from the group consisting of polysilicon, --Si--Si--, silicon carbide, --Si--C--, and silicon nitride, --Si--N--; and wherein said reactant gas streams comprise: (1) as the source of silicon and optionally carbide, a di-alkylsilane of the formula R 1 (R 2 )SiH 2 .

Subnanoscale composite, N2-permselective membrane for the separation of volatile organic compounds

A micro/ultrafiltering element (10) and method for making a filter element are provided. The filtering element comprises a multi-level support (26) having a filtering membrane layer (12) formed thereon comprising sintered particles (14) of uniform diameter. The filtering membrane preferably has an average pore size of from about 0.005-10 micrometers. The filter element is capable of being formed in a variety of geometrical shapes based on the shape of the porous support.

Micro and ultrafilters with controlled pore sizes and pore size distribution and method for making

The invention relates to a process for the production of porous, permeable, mineral membranes According to this process, on a porous, permeable substrate is formed a thin layer of at least one mineral compound chosen from among the simple or mixed metal oxides, except aluminum oxide and mixed aluminium oxides, simple or mixed metal hydroxides, except aluminium hydroxide and mixed aluminium hydroxides and mixtures thereof on the basis of a suspension in a liquid of colloidal or non-colloidal particles, said compound or a precursor thereof having particle sizes below 10 μm The suspension is kept in the finely divided state by the continuous application of energy to the reaction medium The thus obtained membrane is dried and then annealed at a temperature between 400° and 1100° C The use of a suspension of ultrafine colloidal or non-colloidal particles makes it possible to obviate the compression stage and obtain microporous layers with very small pore radii

Process for the production of porous, permeable mineral membranes

L'invention a pour objet un procede de fabrication de membranes minerales, poreuses et permeables. The invention relates to a method for manufacturing inorganic membranes, porous and permeable. Selon ce procede, on forme sur un substrat poreux et permeable une couche mince d'au moins un compose mineral choisi parmi les oxydes metalliques simples ou mixtes, sauf l'oxyde d'aluminium et les oxydes mixtes d'aluminium, les hydroxydes metalliques simples ou mixtes, sauf l'hydroxyde d'aluminium et les hydroxydes mixtes d'aluminium, According to this method, is formed on a porous, permeable substrate a thin layer of at least one inorganic compound selected from single or mixed metal oxides, except aluminum oxide and mixed aluminum oxides, single metal hydroxides or mixed, except aluminum hydroxide and mixed aluminum hydroxides, et leurs melanges a partir d'une suspension dans un liquide de particules colloidales ou non colloidales dudit compose ou d'un precurseur dudit compose ayant des dimensions de grains inferieures a 10 um, on seche la membrane ainsi obtenue puis on la soumet a une cuisson a une temperature comprise entre 400 °C et 1100°C. and mixtures thereof from a suspension in a liquid of colloidal particles or colloidal non of said compound or a precursor of said compound having lower particle sizes to 10 microns, drying the membrane thus obtained is then subjected to baking at a temperature between 400 ° C and 1100 ° C. L'emploi d'une suspension de particules collidales ou non colloidales ultra fines permet d'eviter l'etape de compression et d'obtenir des couches microporeuses de rayons de pores tres faibles. The use of a collidales particle suspension or non ultra fine colloidal avoids the compression step and get microporous layers of very small pore radii.

Process for the production of porous and permeable inorganic membranes

L'invention a pour objet un procede de fabrication de membranes minerales, poreuses et permeables. Selon ce procede, on forme sur un substrat poreux et permeable une couche mince d'au moins un compose mineral choisi parmi les oxydes metalliques simples ou mixtes, sauf l'oxyde d'aluminium et les oxydes mixtes d'aluminium, les hydroxydes metalliques simples ou mixtes, sauf l'hydroxyde d'aluminium et les hydroxydes mixtes d'aluminium, et leurs melanges a partir d'une suspension dans un liquide de particules colloidales ou non colloidales dudit compose ou d'un precurseur dudit compose ayant des dimensions de grains inferieures a 10 um, on seche la membrane ainsi obtenue puis on la soumet a une cuisson a une temperature comprise entre 400 °C et 1100°C. L'emploi d'une suspension de particules collidales ou non colloidales ultra fines permet d'eviter l'etape de compression et d'obtenir des couches microporeuses de rayons de pores tres faibles.

Jean Charpin

Papers

Process for the production of porous, permeable mineral membranes

Process for the production of porous and permeable inorganic membranes

Procédé de fabrication de membranes minérales, poreuses et perméables