The invention relates to the use of i) geopolymer and ii) non-brominated, phosphorus- and/or nitrogen-based flame retardants for improving the self-extinguishing properties of a composition comprising polymer. The polymer may be a vinyl aromatic polymer, and may be in a granulate or foam.

Cement-SCM blends employ particle packing principles to increase particle packing density and reduce interstitial spacing between the cement and SCM particles. Particle packing reduces the amount of water required to obtain a cement paste having a desired flow, lowers the water-cementitious material ratio (w/cm), and increases early and long-term strengths. This may be accomplished by providing a hydraulic cement fraction having a narrow PSD and at least one SCM fraction having a mean particle size that differs from the mean particle size of the narrow PSD cement by a multiple of 3.0 or more to yield a cement-SCM blend having a particle packing density of at least 57.0%.

A low-density, high-strength concrete composition that is lightweight and self-compacting or non-self-compacting, with a low weight-fraction of aggregate to total dry raw materials, and a highly-homogenous distribution of a non-absorptive and closed-cell lightweight aggregate such as glass microspheres or copolymer polymer beads or a combination thereof, and the steps of providing the composition or components. Lightweight concretes formed therefrom have low density, high strength-to-weight ratios, and high R-value. The concrete has strength similar to that ordinarily found in structural lightweight concrete but at a lower density, such as an oven-dried density as low as 40 lbs./cu.ft. Such strength-to-density ratios range approximately from above 30 cu.ft/sq.in. to above 110 cu.ft/sq.in., with a 28-day compressive strength ranging from about 3400 to 8000 psi.

A process of sequestering CO.sub.2 is generally described. The process involves the use of geopolymeric precursors to which the CO.sub.2 is added. The process for a solid, cementitious material comprising geopolymer(s) and CO.sub.2.

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.

The invention relates to mortar or concrete produced with a hydraulic binder, comprising aggregates from cinders from the bottom of municipal waste incinerators and/or from slurry from wastewater treatment plants, or other natural or artificial aggregates, of different particle sizes depending of the use thereof as mortar or concrete, and a binder consisting of: glass and/or other pozzolans; pure Portland clinker with gypsum or plaster of Paris, or the resulting cements following the grinding thereof; and/or optionally lime, depending on the quantity of glass and/or pozzolans; all of the materials forming the base of the binder being ground and mixed together until a binder is obtained, together with the aggregates, with cementing mineral neoformations and a strong pozzolanic character.

This geopolymer molding production method comprises: a mixing step (S1) for mixing a first material containing aluminum and silicon with a hydrate of an alkali stimulant containing a hydrate of an alkaline hydroxide and/or a hydrate of an alkaline silicate; a compaction step (S2) for compacting the mixture obtained in the mixing step (S1) into a compacted mixture; and a curing step (S3) for curing the compacted mixture.

A geopolymer cementing fluid with controllable thickening time includes the following components in parts by weight: 100 parts of a cementitious material, 10 parts-30 parts of an activator, 0.2 parts-5 parts of a retarder, 0.4 parts-4 parts of an anti-settling agent, and 30 parts-70 parts of water. The geopolymer cementing fluid of the present invention has the advantages of controllable thickening time, excellent compressive strength, good settlement stability, good rheological properties, green and eco-friendly, and the like. The geopolymer cementing fluid can be better suited for the operations of oil and gas well cementing and ensure cementing safety.

A two-component hybrid coating system which contains both an organic film forming polyacrylate polymer and particles capable of forming a geopolymer is provided. When the two reactive components are combined, a hybrid coating composition is provided containing a film forming organic polyacrylate polymer component and a geopolymer component.

A process for the production of a geopolymer composite. The disclosure further relates to a geopolymer composite, and the use of a geopolymer, a geopolymer in combination with an athermanous additive, or the geopolymer composite in expanded vinyl polymer, preferably vinyl aromatic polymer. Furthermore, the disclosure relates to a process for the production of expandable vinyl aromatic polymer granulate, and expandable vinyl aromatic polymer granulate. Finally, the disclosure relates to expanded vinyl foam, preferably vinyl aromatic polymer, and to a masterbatch comprising vinyl polymer and a), b), or c).