A brief history and review of geopolymer technology is presented with the aim of introducing the technology and the vast categories of materials that may be synthesized by alkali-activation of aluminosilicates. The fundamental chemical and structural characteristics of geopolymers derived from metakaolin, fly ash and slag are explored in terms of the effects of raw material selection on the properties of geopolymer composites. It is shown that the raw materials and processing conditions are critical in determining the setting behavior, workability and chemical and physical properties of geopolymeric products. The structural and chemical characteristics that are common to all geopolymeric materials are presented, as well as those that are determined by the specific interactions occurring in different systems, providing the ability for tailored design of geopolymers to specific applications in terms of both technical and commercial requirements.

Geopolymer technology: the current state of the art

Spectacular technological progress has been made in the last few years through thedevelopment of new materials such as «geopolymers», and new techniques, such as «sol-gel». New state-of-the-art materials designed with the help of geopolymerization reactions are opening up new applications and procedures and transforming ideas that have been taken for granted in inorganic chemistry. High temperature techniques arc no longer necessary to obtain materials which are ceramic-like in their structures and properties

Geopolymers : inorganic polymeric new materials

http://www.personal.psu.edu/faculty/g/u/gur/cement%20for%20the%20future.pdf

Alkali-activated fly ashes: A cement for the future

The Role of Inorganic Polymer Technology in the Development of ‘Green Concrete’

The geopolymerisation of alumino-silicate minerals

Geopolymer Chemistry and Applications

Spectacular technological progress has been made in the last few years through the development of new materials such as ‘geopolymers’, and new techniques, such as ‘sol-gel’. New state-of-the-art materials designed with the help of geopolymerisation reactions are opening up new applications and procedures and transforming ideas that have been taken for granted in inorganic chemistry. High temperature techniques are no longer necessary to obtain materials which are ceramiclike in their structures and properties. These materials can polycondense just like organic polymers, at temperatures lower than 100 deg. C. This new generation of materials, whether used pure, with fillers or reinforced, is already finding applications in all fields of industry. Some examples:


pure: for storing toxic chemical or radioactive waste, etc.


filled: for the manufacture of special concretes, molds for molding thermoplastics, etc.


reinforced: for the manufacture of molds, tooling, in aluminum alloy foundries and metallurgy, etc.

Geopolymers and geopolymeric materials

Geopolymer cement, high-alkali (K-Ca)-Poly(sialate-siloxo) cement, results from an inorganic polycondensation reaction, a so-called geopolymerisation yielding three dimensional zeolitic frameworks. High-tech Geopolymer K-Poly(sialate-siloxo) binders, whether used pure, with fillers or reinforced, are already finding applications in all fields of industry. These applications are to be found in the automobile and aeronautic industries, non-ferrous foundries and metallurgy, civil engineering, plastics industries, etc. Geopolymer cement hardens rapidly at room temperature and provides compressive strengths in the range of 20 MPa, after only 4 hours at 2 0°C, when tested in accordance with the standards applied to hydraulic binder mortars. The final 28-day compression strength is in the range of 70-100 MPa.The behaviour of geopolymeric cements is similar to that of zeolites and feldspathoids; they immobilize hazardous materials within the geopolymeric matrix, and act as a binder to convert semi-solid wastes into adhesive solids. Their unique properties which include high early strength, low shrinkage, freeze-thaw resistance, sulphate resistance and corrosion resistance, make them ideal for long term containment in surface disposal facilities. These high-alkali cements do not generate any Alkali-Aggregate-Reaction. Preliminary study involving 27 Al and 29 Si MASNMR spectroscopy and the proposed structural model, reveal

/pdf/properties-of-geopolymer-cements-29zfuh37wg.pdf

Properties of geopolymer cements

CO[sub 2] related energy taxes are focusing essentially on fuel consumption, not on actual CO[sub 2] emission measured at the chimneys. Ordinary Portland cement, used in the aggregates and industries, results from the calcination of limestone and silica. The production of 1 ton of cement directly generates 0.55 tons of chemical-CO[sub 2] and requires the combustion of carbon-fuel to yield an additional 0.40 tons of CO[sub 2]. The 1987 1 billion metric tons world production of cement accounted for 1 billion metric tons of CO[sub 2], i.e., 5% of the 1987 world CO[sub 2] emission. A world-wide freeze of CO[sub 2] emission at the 1990 level as recommended by international institutions, is incompatible with the extremely high cement development needs of less industrialized countries. Present cement production growth ranges from 5% to 16% and suggests that in 25 years from now, world cement CO[sub 2] emissions could equal 3,500 million tons. Eco-taxes when applied would have a spectacular impact on traditional Portland cement based aggregates industries. Taxation based only on fuel consumption would lead to a cement price increase of 20%, whereas taxation based on actual CO[sub 2] emission would multiply cement price by 1.5 to 2. A 25--30% minormore » reduction of CO[sub 2] emissions may be achieved through the blending of Portland cement with replacement materials such as coal-fly ash and iron blast furnace slag.« less

/pdf/global-warming-impact-on-the-cement-and-aggregates-qpxbk5duac.pdf

Joseph Davidovits

Papers

Geopolymers : inorganic polymeric new materials

Geopolymer Chemistry and Applications

Geopolymers and geopolymeric materials

Properties of geopolymer cements

Global warming impact on the cement and aggregates industries