Method for producing a supplementary cementitious material from concrete waste and similar materials, supplementary cementitious material obtainable by the method, use of the supplementary cementitious material for making hydraulic building materials and alkali activated binders, method for manufacturing alkali activated binders, composite binders and alkali activated binders comprising the supplementary cementitious material, and use of the composite binder for making hydraulic building materials.

The present disclosure relates to the technical field of preparation of supercapacitor and geopolymeric concrete and discloses a carbon nanotube fly ash composite material and a preparation method and use thereof. The carbon nanotube fly ash composite material comprises an acidified carbon nanotube fiber fabric and a fly ash compound attached to the acidified carbon nanotube fiber fabric, wherein the fly ash compound comprises a cementitious material, a fine aggregate, an alkali activator, and carbon fibers, wherein the cementitious material is a mixture of fly ash, slag, and silica fume. The carbon nanotube fly ash composite material has desirable strength, ductility, and specific surface area, and an asymmetric supercapacitor prepared with the carbon nanotube fly ash composite material has stable properties, high charge-discharge efficiency, and high energy density and power density, and can be utilized in the aspects of large-capacity energy storage such as dwelling, transportation and industrial application.

Geopolymer compositions incorporating slag or other alumino-silicate and calcium containing binder components are described. The geopolymer compositions incorporate C-(N)-A-S-H/C-A-S-H gels providing improved adhesion strength and resistance to chemical attack. Methods of methods of making and using the geopolymers are further described, with the embodied geopolymers being compatible with multiple conventional application processes, including pouring, spraying, screeding, and troweling.

A method for producing supplementary cementitious material. The method comprises contacting a mineral stream with an acid to form an activated mineral stream; reducing the moisture content of the mineral stream; and comminuting the mineral stream to form a supplementary cementitious material. A method of extracting a metal from a mineral stream. The method comprises contacting a mineral stream with an acid to form an activated mineral stream; filtering the activated mineral stream to extract leach liquor comprising the metal; and neutralizing the acid.

The present disclosure provides a potassium aluminosilicate-based nanogel precursor additive and use thereof in a low calcium system-based geopolymer, belonging to the technical field of geopolymer additives. In the present disclosure, the potassium aluminosilicate-based nanogel precursor additive has a high-activity and potassium aluminosilicate-based short-chain structure, and is a precursor of the low calcium system-based geopolymer. The additive includes K.sub.2O, SiO.sub.2, and Al.sub.2O.sub.3, and has a K/Si molar ratio of 1.0 to 4.0 and an Al/Si molar ratio of 0.25 to 1.5. The potassium aluminosilicate-based nanogel precursor additive can be added to a matrix material of the low calcium system-based geopolymer, to effectively optimize a hydration process, balance an internal reaction, and improve a pore structure of the low calcium system-based geopolymer such as metakaolin, thereby improving mechanical properties. The additive effectively avoids harsh curing conditions, uneven hydration reaction.

A method of preparing an enhanced reactivity pozzolan may include: contacting a starting pozzolan with a catalyst material to form a mixture of the starting pozzolan and the catalyst material; reacting the mixture of starting pozzolan and catalyst material during an induction period to form reaction products; and recovering the enhanced reactivity pozzolan.