The invention concerns a batch for the production of a refractory product, a process for the production of a refractory product, a refractory product as well as the use of a refractory product.

A process for preparing a refractory brick, comprises: mixing a refractory aggregate and a binder composition to obtain a refractory mixture wherein the binder composition comprises:

(a) carbohydrate reactant(s) comprising reducing sugar(s) or carbohydrate reactant(s) that yield reducing sugar(s) in situ under thermal conditions and nitrogen-containing reactant(s) and/or

(b) curable reaction product(s) of reducing sugar(s) and nitrogen-containing reactant(s) pressing the refractory mixture to obtain a moulded refractory brick; and firing the moulded refractory brick.

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

The invention concerns a batch for the production of a refractory magnesia-carbon product or a refractory alumina-magnesia-carbon product, a process for the production of a refractory magnesia-carbon product or a refractory alumina-magnesia-carbon product, a refractory magnesia-carbon product or a refractory alumina-magnesia-carbon product as well as the use of a magnesia-carbon product or a refractory alumina-magnesia-carbon product.

The invention concerns a batch for the production of a refractory magnesia-carbon product or a refractory alumina-magnesia-carbon product, a process for the production of a refractory magnesia-carbon product or a refractory alumina-magnesia-carbon product, a refractory magnesia-carbon product or a refractory alumina-magnesia-carbon product as well as the use of a magnesia-carbon product or a refractory alumina-magnesia-carbon product.

A castable refractory composition may include from 5% to 95% by weight of alumina, aluminosilicate, or mixtures thereof; from 0.5% to 1.5% by weight alkaline earth metal oxide and/or hydroxide, and 0.1% to 5% by weight of silica having a surface area of at least about 10 m.sup.2/g. The refractory composition may include no more than 0.5% by weight of cementitious binder. The refractory composition may release less than 25 cm.sup.3 of hydrogen gas per kilogram of castable refractory composition upon addition of water. The refractory compositions may set on addition of water.

A castable refractory composition may include from 5% to 95% by weight of alumina, aluminosilicate, or mixtures thereof; from 0.5% to 1.5% by weight alkaline earth metal oxide and/or hydroxide, and 0.1% to 5% by weight of silica having a surface area of at least about 10 m.sup.2/g. The refractory composition may include no more than 0.5% by weight of cementitious binder. The refractory composition may release less than 25 cm.sup.3 of hydrogen gas per kilogram of castable refractory composition upon addition of water. The refractory compositions may set on addition of water.

The present disclosure relates to an electrolytic cell for the production of aluminium by reducing alumina. The cell may comprise a sidewall including at least one side block. The side block may comprise an aluminous material having an apparent porosity of less than about 10% and a composition, as a weight percentage on the basis of the aluminous material and for a total of about 100%, such that: Al2O3>about 50%, beta-alumina being less than about 20% of the weight of the aluminous material, oxides that are less reducible than alumina at 1000 C.<about 50%, Na2O<about 3.9%, and other components<about 5%.

The present disclosure relates to an electrolytic cell for the production of aluminium by reducing alumina. The cell may comprise a sidewall including at least one side block. The side block may comprise an aluminous material having an apparent porosity of less than about 10% and a composition, as a weight percentage on the basis of the aluminous material and for a total of about 100%, such that: Al2O3>about 50%, beta-alumina being less than about 20% of the weight of the aluminous material, oxides that are less reducible than alumina at 1000 C.<about 50%, Na2O<about 3.9%, and other components<about 5%.

A powder is disclosed having a coarse fraction representing more than 60% and less than 85% of the powder, as a weight percentage on the basis of the oxides, and that is constituted of particles having a size greater than or equal to 50 m, referred to as coarse particles, the powder comprising at least 5% of coated grains having a size greater than or equal to 50 m, as a weight percentage on the basis of the oxides of the powder, and a fine fraction, forming the balance to 100% as a weight percentage on the basis of the oxides, constituted of particles having a size of less than 50 m, referred to as matrix particles. The powder can be applied in combustion chambers in which the temperature may reach 1400 C.