Moulding material for producing a clay-bonded mould, and use thereof in a moulding material cycle

A molding material for production of a clay-bound mold, wherein the molding material comprises:

• a mold base material
• a smectite-containing clay in a concentration of 4.5% to 16% by weight, based on the mass of the molding material,
• one or more dehydratable inorganic compounds that eliminate water at a temperature of 150° C. or more, where the total concentration of said dehydratable inorganic compounds is 5% to 60% by weight, based on the mass of the smectite-containing clay,
• water in a concentration of 1.5% to 10% by weight, based on the mass of the molding material,
• carbon in a concentration of 1.5% by weight or less, based on the mass of the molding material.