Abstract: A silicon nitride porous body (5) obtained by nitriding a molded body having metallic silicon (3) as a main component, the porous body having a porous structure with an average pore diameter of 3 &mgr;m or above, and wherein the total content of silicon and nitrogen is 95% or above and the nitridation ratio of silicon is 90% or above. The silicon nitride porous body has a porous structure with a large average pore diameter, with a test specimen cut out from the porous body exhibiting large thermal conductivity and a small thermal expansion coefficient, and can be suitably used in a component for purifying gas and/or solution such as a ceramic filter.

Abstract: The invention is directed at a mullite-aluminum titanate porous diesel particulate filter constituting a porous ceramic body containing, expressed in terms of weight percent of the total body, of 60-90%, preferably 70-80%, most preferably 70% iron-aluminum titanate solid solution having a stoichiometry of Al2(1−x)Fe2xTiO5, where x is 0-0.1, and 10-40%, preferably 20-30%, most preferably 30% mullite (3Al2O3.2SiO2), and consists essentially, expressed in terms of weigh percent on the oxide basis, of 3 to 15% SiO2, 55 to 65% Al2O3, 22 to 40% TiO2, and 0 to 10% Fe2O3, and being useful for filtration of diesel exhaust. The inventive diesel particulate filter exhibits high interconnected open porosity and large median pore size, in combination with high permeability when fired to a temperature of between 1650° to 1700° C., along with high thermal shock resistance and good filtration capability.

Abstract: This invention is a method of manufacturing oxide porous bodies and components of alumina and magnesia, using alumina and magnesia powders as raw materials, wherein (1) cold isostatic pressure (CIP) of at least 100 MPa is applied to the materials to introduce a plastic deformation with lattice disorder in the surface vicinity without external changes in the particles, (2) by sintering (calcining) the powders with the above described plastic deformation, the microscopic plastic deformation is removed and, at the same time, formation and growth of necks between grains is induced, (3) from the above described steps (1) and (2), a highly porous body with a structure constituted by a three dimensional network of grains connected through the necks is produced.

Abstract: Strong, high-surface-area honeycombs of alumina or other ceramic composition are provided by compounding and shaping a moldable ceramic powder extrusion batches including a cellulosic temporary binder and a high-surface-area boehmite precursor for a permanent binder, hydrating the shaped honeycomb to develop a boehmite binding phase, and calcining the hydrated body to develop the binder and provide a ceramic honeycomb of high strength and porosity.

Abstract: An open-cell glass crystalline porous material made from hollow microspheres which are cenospheres obtained from fly ash, having an open-cell porosity of up to 90 vol. % is produced. The cenospheres are separated into fractions based on one or more of grain size, density, magnetic or non-magnetic, and perforated or non-perforated. Selected fractions are molded and agglomerated by sintering with a binder at a temperature below the softening temperature, or without a binder at a temperature about, or above, the softening temperature but below the temperature of liquidity. The porous material produced has an apparent density of 0.3-0.6 g/cm3, a compressive strength in the range of 1.2-3.5 MPa, and two types of openings: through-flow wall pores in the cenospheres of 0.1-30 micrometers, and interglobular voids between the cenospheres of 20-100 micrometers.

Abstract: The present invention is a porous sound-absorbing ceramic form made of a porous ceramic material with communicating pores and having a bulk specific gravity of 0.5 to 1.0. The porous ceramic material consists essentially of 100 parts by weight of perlite having a particle diameter of 0.50 to 2.0 mm, 100 to 200 parts by weight of at least one sintered material selected from the group consisting of fly ash, chamotte, wollastonite, slag, silica, volcanic ejecta, rock, and clay mineral as a matrix material, and 10 to 20 parts by weight of an inorganic binder, which have been sintered so that the matrix material, together with the binder, surrounds the perlite particles. The perlite particles form communicating openings at mutually contacting portions thereof, so that the internal pores are communicating pores.

Abstract: There is provided an improved ceramic foam filter for use in filtering molten metals, metal prepared from a ceramic slurry containing silicon carbide, a colloidal silica binder and at least 10 percent of fumed silica. The filter has enhanced strength properties.

Abstract: A method of making a molecularly imprinted porous structure makes use of a surfactant analog of the molecule to be imprinted that has the imprint molecule portion serving as the surfactant headgroup. The surfactant analog is allowed to self-assemble in a mixture to create at least one supramolecular structure having exposed imprint groups. The imprinted porous structure is formed by adding reactive monomers to the mixture and allowing the monomers to polymerize, with the supramolecular structure serving as a template. The resulting solid structure has a shape that is complementary to the shape of the supramolecular structure and has cavities that are the mirror image of the imprint group. Similarly, molecularly imprinted particles may be made by using the surfactant to create a water-in-oil microemulsion wherein the imprint groups are exposed to the water phase.

Abstract: A lightweight heat-insulating building material which has excellent frost resistance and a low price is provided. The lightweight heat-insulating building material having frost resistance is produced by molding a mixture of raw materials containing glass powder, a foaming agent, a crystallization inhibitor, and a frost inhibitor so as to form a molded body, and firing the molded body so as to foam the molded body.

Abstract: A mesoporous ceramic material is provided having a pore size diameter in the range of about 10-100 nanometers produced by templating with a ceramic precursor a lyotropic liquid crystalline L3 phase consisting of a three-dimensional, random, nonperiodic network packing of a multiple connected continuous membrane. A preferred process for producing the inesoporous ceramic material includes producing a template of a lyotropic liquid crystalline L3 phase by mixing a surfactant, a co-surfactant and hydrochloric acid, coating the template with an inorganic ceramic precursor by adding to the L3 phase tetramethoxysilane (TMOS) or tetraethoxysilane (TEOS) and then converting the coated template to a ceramic by removing any remaining liquids.

Abstract: The object of the present invention is to save labor, reduce cost, and to make detergents and wax unnecessary. Water quality improving materials used in a washing device are provided, wherein; raw ceramic powder material containing tourmaline is adhered on the surfaces of ceramic carriers, and then fired to form tourmaline containing films, whereby washing powder is improved by activating water and the contained boric silica S1, S2 . . . adheres onto the surface W of an automobile, etc. As a form thereof, the boric silica S1, S2 . . . is adhered by an electrode position action due to the electrical charges generated by tourmaline and the water is activated by these electrical charges.

Abstract: The invention concerns a new and improved method for the production of porous and formed bodies with polycrystalline structure that meets the high quality requirements of the usually excellent material characteristics of porous and formed bodies based on silicon nitride and, at the same time, at least considerably reduces known disadvantages of other state-of-the-art techniques. In this, it is provided to first precompress the silicon nitride powder mix with a modal particle distribution of coarse and fine particles to form a green body, and to subsequently bake it using a temperature-based sintering process.

Abstract: Ultra-high temperature, light-weight, black ceramic insulation having a density ranging from about 0.12 g/cc. to 0.6 g/cc. such as ceramic tile is obtained by pyrolyzing siloxane gels derived from the reaction of at least one organo dialkoxy silane and at least one tetralkoxy silane in an acid or base liquid medium. The reaction mixture of the tetra- and dialkoxy silanes also may contain an effective amount of a mono- or trialkoxy silane to obtain the siloxane gels. The siloxane gels are dried at ambient temperatures and pressures to form siloxane ceramic precursors without significant shrinkage. The siloxane ceramic precursors are subsequently pyrolyzed, in an inert atmosphere, to form the black ceramic insulation comprising atoms of silicon, carbon and oxygen. The ceramic insulation can be characterized as a porous, uniform ceramic tile resistant to oxidation at temperatures ranging as high as 1700° C.

Abstract: A structure for use in high temperature applications and including a porous ceramic material consisting essentially of about 50-90 percent by weight iron or magnesium stabilized aluminum titanate (AlTiO5) and about 10-50 percent by weight strontium feldspar (SrO.Al2O3.2SiO2), and having a coefficient of thermal expansion over a temperature range from room temperature to 1000° C. of about −10×10−7/° C. to +15×10−7/° C., a heat capacity at 500° C. greater than 3.2 J/cm3K, a porosity of about 15-50 percent by volume, preferably 40-50 percent by volume, and a median pore size of about 5-50 micrometers, preferably 8-15 micrometers. The structure is especially useful as a diesel exhaust particulate filter.

Abstract: A dispersion is made up of water refractory particles and material for forming pores and a polymeric dispersion. A water sensitive destabilising agent is added to increase the viscosity of the mix and cause it to solidify to form a green body which is removed from a mould and then heated and sintered.

Abstract: A homogeneous bulky porous ceramic material is provided, the average pore diameter D50 of which is less than 4 &mgr;m and the closed porosity of which is less than 2 &mgr;m, and having a bubble point that matches the pore diameter measured on the material. A hollow fiber based on the material and a module employing such fibers together with a paste constituting a precursor for the material and including a pore-forming agent are also provided.

Abstract: A method of producing ceramic foam wherein a precursor including an AlCl3 (Pri2O) complex is decomposed to form a mixture of a polymerizing species and liquid isopropyl chloride and the mixture is foamed. The foamed mixture is sintered and/or calcined to produce a ceramic foam.

Abstract: A silicon nitride porous body which is a body having a generally columnar outer shape and at least two through-holes mutually parallel to one another and which has generally perpendicularly oriented columnar crystals on the surface of the through-holes.

Abstract: An improved porous article and a method for forming such porous article are provided. A mixture of ceramic or metal particles and pliable organic hollow spheres is prepared in a liquid, typically as a suspension. The article is formed by pressing, slip casting, extruding or injection molding the mixture. The article is dried to remove the liquid, and then is fired so that the particles are bonded such as by sintering, and the organic spheres are eliminated, resulting in a strong porous article having uniformly spaced interconnected voids.

Abstract: A method for molecular imprinting polymers with large biomolecules. The imprinted polymer composite is made by the interfacial polymerization of a monomer in the presence of the print molecule and host polymer. Since polymerization occurs at the interface between an organic solvent and an aqueous solution, the print molecule can be disposed in the phase that allows the print molecule to remain in its native configuration. The choice of the host polymer and the monomer to be polymerized can be varied to enhance the specificity of the composite toward the biomolecule that is selected to be imprinted.

Abstract: An article of manufacture includes a metallic nonfoam region, and a ceramic foam region joined to the metallic region. The ceramic foam region is an open-cell solid ceramic foam made of ceramic cell walls having an intracellular volume therebetween. The ceramic is preferably alumina. The intracellular volume may be empty porosity, or an intracellular metal such as an intracellular nickel-base superalloy.

Abstract: A method of making a molecularly imprinted porous structure makes use of a surfactant analog of the molecule to be imprinted that has the imprint molecule portion serving as the surfactant headgroup. The surfactant analog is allowed to self-assemble in a mixture to create at least one supramolecular structure having exposed imprint groups. The imprinted porous structure is formed by adding reactive monomers to the mixture and allowing the monomers to polymerize, with the supramolecular structure serving as a template. The resulting solid structure has a shape that is complementary to the shape of the supramolecular structure and has cavities that are the mirror image of the imprint group. Similarly, molecularly imprinted particles may be made by using the surfactant to create a water-in-oil microemulsion wherein the imprint groups are exposed to the water phase.

Abstract: Provided is a ceramic porous body which uses a binder made of a glass excellent in acid resistance and alkali resistance which can be used for a long period of time as a filtration filter etc.

Abstract: A process for producing an SiO2 shaped body which is vitrified in a partial region or completely, in which process an amorphous, porous SiO2 preform is sintered or vitrified by contactless heating by means of laser radiation, by means of which contamination of the SiO2 shaped body with foreign atoms is avoided.

Abstract: An improved method for preparing low density ceramics is described wherein the process incorporates paper residuals which are a by-product of the paper recycling process. The method for making a low density-ceramic comprises the steps of: a) providing a paper residual comprising from about 0.5 to about 99 percent, by weight, of at least one filler, from about 0 to about 20 percent, by weight, of a dye, from about 0 to about 10 percent, by weight, of an ink, from about 0.5 to about 99.5 percent, by weight, of paper fiber, and from about 0 to about 30 percent, by weight, of other components, based on a dry weight of the residual; b) admixing a ceramic material with the paper residual, the ceramic material comprising up to about 90%, by weight, of the admixture, based on a dry weight of the admixture; c) forming the admixture into a desired shape; and d) firing the admixture to a temperature ranging from about 1850° F. to about 2900° F.

Abstract: A ceramic article which consists essentially, by weight on the oxide basis, of 10-25% SiO2, 65-85% Al2O3, and 2-12% Li2O and comprises beta-eucryptite as a first phase having a negative component in thermal expansion and a melting point Tm1, and a second phase having a positive component in thermal expansion which is higher than the component in thermal expansion of the first phase and a melting point Tm2, wherein Tm2>Tm1, wherein the first phase is at most 50% by weight of the ceramic, and wherein the ceramic is characterized by microcracking. Tm2 is at least 1800° C. The ceramic article exhibits a near zero coefficient of thermal expansion from room temperature to 800° C., a high refractoriness, and a high resistance to thermal shock properties which make the inventive ceramic extremely desirable in high temperature applications, such as filters for diesel exhaust engines.

Abstract: A preform for use in a metal matrix composite, particularly for a magnesium metal composite. In the preform the reinforcing material typically is silicon carbide, boron nitride, titanium nitride, carbon or graphite. The binder used in the preform is sintered magnesium fluoride, which avoids the known problems which result from the high reactivity of molten magnesium metal with other binders, such as silica and alumina, which results in the formation of magnesium oxide in the reinforced composite. The presence of magnesium oxide crystals in the metal matrix adversely affects the properties of the composite. The preform generally has a void volume of from about 50% to about 95%.

Abstract: A ceramic comprising predominately a cordierite-type phase approximating the stoichiometry Mg2Al4Si5O18 and having a coefficient of thermal expansion (25-800° C.) of greater than 4×10−7/° C. and less than 13×10−7/° C. and a permeability and a pore size distribution which satisfy the relation 2.108 (permeability)+18.511 (total pore volume)+0.1863 (percentage of total pore volume comprised of pores between 4 and 40 micrometers)>24.6. The ceramic is suitable in the fabrication of cellular, wall-flow, diesel particulate filters having a pressure drop in kPa that at an artificial carbon soot loading of 5 grams/liter and a flow rate of 26 scfm is less than 8.9−0.035 (number of cells per square inch)+300 (cell wall thickness in inches), a bulk filter density of at least 0.60 g/cm3 and a volumetric heat capacity of at least 0.67 J cm−3 K−1 as measured at 500° C.

Abstract: The process of the invention characterized in that to 100 parts by weight of a silicate powder having 2000-8000 m2/g specific surface, 1-10 parts by weight of gas-forming material with particle size of 10-100 &mgr;m and 0.5-15 parts by weight of montmorillonite, 0.5-2 parts by weight of alkali hydrogen phosphate or alkali dihydrogen phosphate or a mixture of alkali metal phosphate and sodium silicate in form of aqueous solution, 0.01-5 parts by weight of rare earth metal oxide or a mixture of such oxides were added, then the mixture obtained is homogenized, pre-dried, coated with 1-5 parts by weight of titanium oxide and/or titanium oxide hydroxide and/or aluminum oxide hydroxide, then subjected to heat treatment at 720-1000° C., and the mixture obtained is molded. The subject of the invention: also the product of the above process.

Abstract: The present invention relates to the extrusion freeform fabrication of low cost, in situ, metallic foam components having oriented microstructures and improved mechanical properties such as energy absorption and specific stiffness. The present invention relates to the freeform fabrication of metallic foams to form parts having complex geometry that demonstrate superior mechanical properties and energy absorbing capacity.

Abstract: An object of the invention is to integrate porous ceramics and dense ceramics with an adequately high bonding strength.

Abstract: The present invention is a porous sound-absorbing ceramic form made of a porous ceramic material with communicating pores and having a bulk specific gravity of 0.5 to 1.0. The porous ceramic material consists essentially of 100 parts by weight of perlite having a particle diameter of 0.50 to 2.0 mm, 100 to 200 parts by weight of at least one sintered material selected from the group consisting of fly ash, chamotte, wollastonite, slag, silica, volcanic ejecta, rock, and clay mineral as a matrix material, and 10 to 20 parts by weight of an inorganic binder, which have been sintered so that the matrix material, together with the binder, surrounds the perlite particles. The perlite particles form communicating openings at mutually contacting portions thereof, so that the internal pores are communicating pores.

Abstract: A composite material has a quartz glass phase and a complex compound phase compounded with the quartz glass phase, which is made of one or more compounds selected from a group of silicon carbide, silicon nitride, silicon, titanium nitride and titanium carbide, as a main ingredient. The composite material can be used instead of quartz glass, and can prevent the generations of microcrack, tipping and particles after the mechanical working.

Abstract: A spherical porous ceramic body and the production method thereof are provided. As to the porous ceramic body, the total volume of the pores having a pore radius of from 1.8 nm to 100 &mgr;m is about 0.25 cm3/g or more, the mode of pore radius of the pores is from about 1 &mgr;m to about 6 &mgr;m and the packing density is from about 0.7 g/cm3 to about 1 g/cm3. The porous ceramic body is suitably used as a carrier for a catalyst and has high mechanical strength.

Abstract: A combination dense/porous structure includes a porous element having an outer surface defining a shape having a bulk volume, the element includes a continuous framework having struts defining a plurality of interconnecting interstices throughout the bulk volume. The porous element has interconnecting interstices extending throughout the volume and opening through the surface. The combination dense/porous structure also includes a dense element formed from a material and having a sintered density of at least 95%, contacting at least a portion of the porous element; and an interconnection zone formed by the inter-penetration of the material forming the dense element into the porous element. The combination dense/porous structures are particularly useful as bone substitute materials and extended release delivery systems, preferable sustained release, for physiologically active agents.

Abstract: A lightweight heat-insulating building material which has excellent frost resistance and a low price is provided. The lightweight heat-insulating building material having frost resistance is produced by molding a mixture of raw materials containing glass powder, a foaming agent, a crystallization inhibitor, and a frost inhibitor so as to form a molded body, and firing the molded body so as to foam the molded body.

Abstract: The invention relates to a lightweight substance molded body made of a lightweight aggregate and a sintering auxiliary agent, wherein said molded body consist of a sintering product containing 60-95 wt. % lightweight aggregate with 40-5 wt. % water-soluble alkali silicate.

Abstract: A porous sintered body of a calcium phosphate-based ceramic having a porosity of 80% or more. The porous sintered body is produced by a method comprising the steps of: (1) preparing a slurry comprising a calcium phosphate-based ceramic powder, a water-soluble high molecular compound and a nonionic surface active agent; (2) stirring the slurry vigorously to froth the slurry; (3) solidifying the frothed slurry into a gel; and (4) drying and sintering the gel.

Abstract: The present invention relates to porous calcium zirconate/magnesia composites having a thermally and chemically stable porous structure, which consist of sintered compacts having a fine composite structure stable under high temperatures due to uniformly dispersed equimolar amounts of calcium zirconate [CazrO3] and magnesia [MgO] and controlled grain growth, and a method of producing the same, and the present porous composites are useful as, for instance, a functional material for filtering highly corrosion resistant materials, lightening members used at super-high temperatures, catalyst carriers, insulation or sound-absorbing materials, and the like.

Abstract: This invention relates to a method for treating various kinds of drain water and waste liquid which treatment now becomes a problem, for example, drain water and waste liquid containing hardly removable phosphorus and nitrogen, waste liquid containing organochlorine compounds such as tetrachloroethylene, etc., excretive drain water from a piggery containing organonitrogen compounds at a high level, waste liquid containing heavy metals such as lead, hexavalent chromium, cadmium and the like, drain water from dairy product plants, fishery processing plants, slaughterhouses, etc. which contains water soluble protein at a high level, drain water from pulp plants, photo developing waste liquid, car wash drain water containing a mixture of car polishing wax and detergent and the like by the use of porous ceramics provided with amorphous pore surfaces.

Abstract: A fibrous ceramic mat is molded from a slurry of ceramic fibers and/or ceramic micropartides and/or a metal. The mat is impregnated with a sol prior to drying. A catalyst for the sol is introduced into the mat to cause the sol to gel. The sol-gel binder forms bonds so that the mat is dimensionally stabilized. The mat is dried to produce the desired ceramic insulation that has preferably a consistent microstructure and a fully gelled sol-gel binder through its entire thickness. If we use a metal, it corrodes (i.e., oxidizes) or otherwise reacts to form a refractory binder that augments the sol and reduces the need to infuse sol incrementally to achieve strength. Using metal powder significantly reduces the cost of manufacture.

Abstract: A structure made predominately of an NZP-type phase having the general formula RxZ4P6−ySiyO24, where 0≦x≦8, 0≦y≦6, R is Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, Y, and/or lanthanides, and Z is Zr, Ti, Nb, Ta, Y, and/or lanthanidess, and optionally a sintering additive. The structure has an open porosity of at least 20% by volume, median pore diameter in micrometers of at least a value defined by the quantity [10−0.10(% open porosity)], both as measured by mercury porosimetry, and four-point modulus of rupture as measured on a solid rod of circular cross section, of at least 300 psi. Method of making the structure involves forming a mixture of NZP-forming raw material powders that are metal oxide sources capable of reacting to form an NZP-type reaction product, and/or pre-reacted powder having the above general formula.

Abstract: Disclosed is a rigid fine-celled light-weight foam composition and a method of producing it which has improved retention of liquids by absorption/adsorption which improves the thermal insulation and fire retardant properties of the fine-celled foam particularly suited for use in double walled tanks and hollow canopies, building panels, profiles, and the like.

Abstract: The process of the present invention comprises a method for fabricating shaped monolithic ceramics and ceramic composites through displacive compensation of porosity, and ceramics and composites made thereby. The method of the present invention includes three basic steps: 1) Synthesis or other acquisition of a porous preform: A porous preform with an appropriate composition, pore fraction, and overall shape is prepared or obtained. The pore fraction of the preform is tailored so that the reaction-induced increase in solid volume can compensate partially or completely for such porosity. It will be understood that the porous preform need only be sufficiently dimensionally stable to resist the capillary action of the infiltrated liquid reactant; 2) Infiltration: The porous preform is infiltrated with a liquid reactant; and 3) Reaction: The liquid reactant is allowed to react partially or completely with the solid preform to produce a dense, shaped body containing desired ceramic phase(s).

Abstract: The present invention relates to a porous aluminum oxide structure comprising Al2O3 and Zr, the structure having an open porosity greater than about 30% and an average pore size from about 20 nm to about 1000 nm, wherein the Zr, expressed as ZrO2, has a concentration less than about 5 weight % of the weight of the Al2O3.

Abstract: A method of making a molecularly imprinted porous structure makes use of a surfactant analog of the molecule to be imprinted that has the imprint molecule portion serving as the surfactant headgroup. The surfactant analog is allowed to self-assemble in a mixture to create at least one supramolecular structure having exposed imprint groups. The imprinted porous structure is formed by adding reactive monomers to the mixture and allowing the monomers to polymerize, with the supramolecular structure serving as a template. The resulting solid structure has a shape that is complementary to the shape of the supramolecular structure and has cavities that are the mirror image of the imprint group. Similarly, molecularly imprinted particles may be made by using the surfactant to create a water-in-oil microemulsion wherein the imprint groups are exposed to the water phase.

Abstract: A porous sintered body in which the leaching amounts of heavy metals are small and having high availability contains 0.5-15 weight % of B2O3, preferably contains 20-60 weight % of Al2O3, 18-60 weight % of SiO2, 1-12 weight % of the sum of Na2O, K2O, Li2O, and P2O5, 1-30 weight % of the sum of CaO, SrO, BaO, and MgO, and 0.5-15 weight % of B2O3.

Abstract: Ultra-high temperature, light-weight, black ceramic insulation having a density ranging from about 0.12 g/cc. to 0.6 g/cc. such as ceramic tile is obtained by pyrolyzing siloxane gels derived from the reaction of at least one organo dialkoxy silane and at least one tetralkoxy silane in an acid or base liquid medium. The reaction mixture of the tetra- and dialkoxy silanes also may contain an effective amount of a mono- or trialkoxy silane to obtain the siloxane gels. The siloxane gels are dried at ambient temperatures and pressures to form siloxane ceramic precursors without significant shrinkage. The siloxane ceramic precursors are subsequently pyrolyzed, in an inert atmosphere, to form the black ceramic insulation comprising atoms of silicon, carbon and oxygen. The ceramic insulation can be characterized as a porous, uniform ceramic tile resistant to oxidation at temperatures ranging as high as 1700° C.

Abstract: A calcium phosphate porous sintered body which comprises spherical pores communicating with one another substantially throughout the body with a porosity of 55% or more and 90% or less, and has an average diameter of the inter-pore communicating parts of 50 &mgr;m or more, a pore diameter of 150 &mgr;m or more, and a three-point bending strength of 5 MPa or more, and a method for producing the same.

Abstract: Ultra-high temperature, light-weight, ceramic insulation such as ceramic tile is obtained by pyrolyzing a siloxane gel derived from the reaction of at least one organo dialkoxy silane and at least one tetralkoxy silane in an acid or base liquid medium. The reaction mixture of the tetra- and dialkoxy silanes may contain also an effective amount of a mono- or trialkoxy silane to obtain the siloxane gel. The siloxane gel is dried at ambient pressures to form a siloxane ceramic precursor without significant shrinkage. The siloxane ceramic precursor is subsequently pyrolyzed, in an inert atmosphere, to form the black ceramic insulation comprising atoms of silicon, carbon and oxygen. The ceramic insulation, can be characterized as a porous, uniform ceramic tile resistant to oxidation at temperatures ranging as high as 1700° C. and is particularly useful as lightweight tiles for spacecraft and other high-temperature insulation applications.