A foaming agent is used for foaming a building material binder paste or a building material slurry for producing porous lightweight-construction and insulating materials. On curing of the foamed slurry, the foam bubbles generate pores in the building material. The foam obtained from the foaming agent is stabilized using a long-chain or medium-chain polycarboxylate ether (PCE). The foaming agent includes a foam-forming ionic surfactant component, at least one fatty alcohol and at least one PCE in an aqueous-organic solvent which is selected from the group of alkyl glycols, alkylene glycols up to C6 alkyl, diglycols and diglycol ethers, and also, optionally, up to a maximum of 20 wt %, based on the mixture, of further ingredients.

A foaming agent is used for foaming a building material binder paste or a building material slurry for producing porous lightweight-construction and insulating materials. On curing of the foamed slurry, the foam bubbles generate pores in the building material. The foam obtained from the foaming agent is stabilized using a long-chain or medium-chain polycarboxylate ether (PCE). The foaming agent includes a foam-forming ionic surfactant component, at least one fatty alcohol and at least one PCE in an aqueous-organic solvent which is selected from the group of alkyl glycols, alkylene glycols up to C6 alkyl, diglycols and diglycol ethers, and also, optionally, up to a maximum of 20 wt %, based on the mixture, of further ingredients.

Disclosed herein are devices, systems, and methods related to an admixture for lightweight, high-performance concrete. The admixture can include a polymeric material; a surfactant; and graphene. In examples, when incorporated into a curable mixture and cured, admixing such admixtures result in a concrete that has a compression strength that is greater than the compression strength of an otherwise identical cured curable mixture that excludes the admixture, the compressive strength being at least 3,000 psi and a maximum density of about 150 lbs/ft.sup.3.

Disclosed herein are devices, systems, and methods related to an admixture for lightweight, high-performance concrete. The admixture can include a polymeric material; a surfactant; and graphene. In examples, when incorporated into a curable mixture and cured, admixing such admixtures result in a concrete that has a compression strength that is greater than the compression strength of an otherwise identical cured curable mixture that excludes the admixture, the compressive strength being at least 3,000 psi and a maximum density of about 150 lbs/ft.sup.3.

A process may involve treating calcium sulfate separated from phosphoric acid with acid to obtain a suspension comprising purified calcium sulfate, separating the purified calcium sulfate in solid form from a liquid phase of the suspension, treating the purified calcium sulfate with water or with a salt- and/or chelate ligand-containing aqueous solution to leach rare earths out of the calcium sulfate, separating the further-purified calcium sulfate in solid form from the liquid phase of the suspension, mixing the purified calcium sulfate that is separated off with admixtures and reducing agents to obtain a raw meal mixture for cement clinker production, burning the raw meal mixture to obtain the cement clinker and thereby forming sulfur dioxide as offgas, and feeding the sulfur dioxide as raw material to sulfuric acid production to produce the sulfuric acid.

A process may involve treating calcium sulfate separated from phosphoric acid with acid to obtain a suspension comprising purified calcium sulfate, separating the purified calcium sulfate in solid form from a liquid phase of the suspension, treating the purified calcium sulfate with water or with a salt- and/or chelate ligand-containing aqueous solution to leach rare earths out of the calcium sulfate, separating the further-purified calcium sulfate in solid form from the liquid phase of the suspension, mixing the purified calcium sulfate that is separated off with admixtures and reducing agents to obtain a raw meal mixture for cement clinker production, burning the raw meal mixture to obtain the cement clinker and thereby forming sulfur dioxide as offgas, and feeding the sulfur dioxide as raw material to sulfuric acid production to produce the sulfuric acid.