摘要:
A ceramic composite mineral filtering membrane including a thin microporous layer adhering to one side of a porous support having greater pore diameters than said thin layer, and having a specific permeability at least 25 % greater than that of an equivalent composite membrane obtained with the same support by the direct deposition, on said side thereof, of the same precursor material of said thin microporous layer, followed by conventional heat treatment; and the preparation thereof, wherein the support is impregnated with a solution of a film-forming organic polymer prior to applying the precursor material (slip) of said thin microporous layer. During subsequent heat treatment, the organic polymer is decomposed and the resulting thin microporous layer has high permeability while being firmly attached to the support.
摘要:
A process for forming a porous inorganic membrane on a porous support is provided. The support is coated with refractory particles which sinter at a first temperature. The coating then is impregnated with an inorganic binder which reacts at a second temperature, lower than the first temperature. The impregnated, coated support then is processed at a temperature at least as high as the second temperature, but less than the first temperature.
摘要:
A free-standing ceramic membrane having pores of substantially uniform size can be formed by partly sintering a cast layer of ceramic particles including more than 60 % of larger particles and up to 40 % of smaller particles as a sintering aid. A composite membrane comprises as a support layer the free-standing ceramic membrane, and an overlying film of partly sintered ceramic particles. Both the support layer and the overlying films may be formed by tape casting dispersions of the particles in solutions of polymeric binder in preferably different volatile liquids.
摘要:
Porous shaped phenolic resin articles are made by partially curing a phenolic resin to a solid, comminuting the resin, forming into a pre-determined shape, and sintering. Porous shaped carbon articles are made by carbonising the sintered material.
摘要:
A filter including a porous support defining one or more channels therethrough, and a porous ceramic membrane layer on a surface of the porous support defining at least one of the one or more channels. The ceramic membrane layer includes an inorganic ceramic composition having the formula SiM p xp C y N z O m H n , where each M p present is independently selected from a p-block element or a d-block element; p is an integer from 1 to 5; for each M p present, xp is independently from about 0 to about 60; y is from about 0 to about 60; z is from about 0 to about 60; m is from about 0 to about 40; and n is zero or nonzero. At least one of y and z is nonzero when p is zero, and p is nonzero when y and z are both zero.
摘要:
Ceramic composite materials that are reinforced with carbide fibers can exhibit ultra-high temperature resistance. For example, such materials may exhibit very low creep at temperatures of up to 2700°F (1480°C). The present composites are specifically engineered to exhibit matched thermodynamically stable crystalline phases between the materials included within the composite. In other words, the reinforcing fibers, a debonding interface layer disposed over the reinforcing fibers, and the matrix material of the composite may all be of the same crystalline structural phase (all hexagonal), for increased compatibility and improved properties. Such composite materials may be used in numerous applications.
摘要:
Non-oxidative direct methane conversion (NDMC) to value-added products, such as H 2 , C 2 hydrocarbons, and aromatics, occurs within a reactor heated to an elevated temperature. The reactor can have a first volume, where a feed gas including methane is provided, separated from a second volume, where a sweep gas is provided, by a dense thin film membrane supported on a porous wall. The thin film membrane is a mixed ionic-electronic permeable membrane that allows H2 generated in the first volume to be transported to the second volume for removal by (or reaction with) the sweep gas. A catalyst can be provided in or adjacent to the first volume. For example, the catalyst can be a metal doped quartz material (e.g., Fe(c)SiO 2 ) or a metal/zeolite material (e.g., Mo/ZSM5). Methane conversion and/or product selectivity in the reactor can be manipulated by control of gas flow rates, reaction temperatures, and/or feed and sweep gas compositions.
摘要:
Изобретение относится к области изготовления изделий из пористой керамики, предназначенной для тонкой очистки жидкостей и газов от различных веществ, например взвесей, бактерий, крупных молекул и других загрязнений. Изобретение направлено на достижение технического результата, заключающегося в повышении качества фильтрующих элементов и улучшении характеристик фильтрации за счет более узкого распределения пор подложки и увеличения равномерности распределения наносимых частиц. Указанный технический результат достигается за счет того, что способ изготовления керамических фильтрующих элементов осуществляют путем формования крупнопористой подложки экструзией из пластичной массы, содержащей а-оксид алюминия с размерами частиц от 7 до 40 мкм, глинистый компонент и боросиликат, последовательного нанесения слоев водной суспензии смеси тонкомолотых веществ, содержащей α-оксид алюминия с размерами частиц от 0,5 до 1,5 мкм, глинистый компонент и боросиликат с одновременным приложением разрежения со стороны, противоположной стороне нанесения слоев, сушки и спекания полученной заготовки, при этом пластичную массу готовят с содержанием глинистого компонента 10 - 12%, а боросиликата - не более 4%, экструзию осуществляют в естественных условиях под углом.
摘要:
The present invention relates to a method of making a monolith having a plurality of channels extending therethrough, the method comprising, providing a suspension of polymer-coated particles in a first solvent; extruding the suspension from a primary orifice, while passing one or more second solvents from a plurality of secondary orifices arranged within the first orifice, into a third solvent, whereby a monolith precursor is formed from the polymer and particles, and sintering the monolith precursor to form a monolith.
摘要:
Procédé de préparation d'un sol-gel d'au moins quatre sels de métaux M 1 , M 2 , M 3 et M 4 aptes et destinés à la préparation d'un matériau de type pérovskite correspondant à la formule générale (I) : A (1-X) A' x B (1-y-U) B' y B" u Ο 3-δ , (I), ledit procédé comprenant les étapes suivantes : - Une étape a) de préparation d'une solution aqueuse de sels hydrosolubles des dits éléments A, A' optionnellement A", B et B', dans les proportions stœchiométriques nécessaires à l'obtention du matériau tel que défini ci-dessus; - Une étape b) de préparation d'une solution hydro-alcoolique d'au moins agent tensioactif non-ionique dans un alcool choisi parmi le méthanol, l'éthanol, le propanol, le propanol, l'isopropanol ou le butanol, mélangé à une solution aqueuse d'ammoniac en une proportion suffisance pour assurer la solubilisation complète dudit agent tensioactif non- ionique dans ladite solution hydro-alcoolique, la concentration dudit agent tensioactif non- ionique dans ladite solution hydro-alcoolique étant inférieure à la concentration micellaire critique; - Une étape c) de mélange de ladite solution aqueuse préparée à l'étape a), avec ladite dispersion alcoolique préparée à l'étape b) pour former un sol; - Une étape d) de séchage dudit sol obtenu à l'étape c), par évaporation du solvant, pour obtenir un sol-gel. Mise en œuvre du procédé pour préparer une membrane céramique.