Various embodiments of the present invention relate to reactive media including calcium. A reactive media includes a vitrified calcium silicate comprising reactive calcium. Various embodiments of the reactive media described herein are useful for removal of anionic impurities such as phosphate from water.

The invention relates to a raw material for producing a refractory product, a use of this raw material, and a refractory product comprising a raw material of this kind.

The invention relates to a batch composition for producing a refractory product, a method for producing a refractory product, a refractory product, and to the use of a synthetic raw material.

A first circumferential wall disposed in a circumference of partition walls has no interface with the outermost circumference partition wall in a circumferential portion constituted by the partition walls whose wall thickness is larger than that of a central portion constituted by the partition walls in a central region. A maximum thickness of a total of the first circumferential wall and a second circumferential wall disposed to surround an outer side of the first circumferential wall is 1.2-3.0 mm, a difference between the maximum thickness and a minimum thickness of the total is 0.2-1.5 mm, and there is satisfied a relation, 0.5(TBTA)SB/SA100(%)9.0 in which TB and TA indicate average thicknesses (m) of the partition walls in the circumferential and central portion respectively, and SB and SA indicate areas (cm.sup.2) of the circumferential portion and the honeycomb structure in the cross section respectively.

The invention relates to a fire-resistant ceramic product, a batch for manufacturing a product of said type, and a process for manufacturing a product of said type.

A lightweight micro-closed-pore corundum composite refractory and a method preparing the same, wherein raw materials of the refractory comprise 95-99 parts by weight of -Al.sub.2O.sub.3 micro-powder and 1-5 parts by weight of dolomite clinker; and additives of the refractory comprise 2-15 parts by weight of nano alumina sol, 5-15 parts by weight of a carbohydrate polymer, and 30-50 parts by weight of an organic alcohol. and the lightweight micro-closed-pore corundum composite refractory is prepared by: mixing and wet grinding the raw materials and the additives to obtain a slurry; placing the slurry in a mold, keeping the mold at 15-25 C. for 6-12 hours and then keeping the mold at 60-90 C. for 6-12 hours, then demolding; drying a demolded green body at 110-200 C. for 24-36 hours, and keeping the green body at 1800-2000 C. for 2-5 hours. A method preparing a lightweight micro-closed-pore corundum composite refractory is also provided. The lightweight micro-closed-pore corundum composite refractory of the present invention has characteristics of low bulk density, small average pore size, high closed porosity, low thermal conductivity, strong thermal shock resistance, abrasion resistance and slag resistance.

The invention relates to a batch for producing an unshaped refractory ceramic product, to a method for producing an unshaped refractory ceramic product, and to an unshaped refractory ceramic product produced by the method.

The invention relates to a raw material for producing a refractory product, a use of this raw material, and a refractory product comprising a raw material of this kind.

Provided are materials for a formed body comprising hexagonal boron nitride and such formed bodies. Also provided are heat-treated formed body obtained by heat-treating the formed bodies. The invention further relates to processes for making the formed body and the heat-treated formed body.

The invention relates to a refractory ceramic batch for the production of an unformed refractory ceramic batch, the use of a batch of this kind for lining metallurgical melting vessels and also a metallurgical melting vessel which is lined with an unformed refractory ceramic product based on a batch of this kind.