Sustainable binders as basis for mass building materials with lower CO2 content

In the coming decades, the building materials industry will face the enormous challenge of significantly reducing its greenhouse gas emissions in order to meet the Paris climate targets. The development and use of sustainable binders to reduce CO2 will play a decisive role.

Climate-friendly cement substitutes offer great potential

Although cement only accounts for between 7 and 20 percent by mass of concrete as a building material, it is responsible for more than 90 percent of the greenhouse gas emissions associated with concrete production. However, as one of the world's largest CO2 emitters (approx. 7 to 8 percent), the cement industry is also obliged to achieve CO2 neutral production by 2050. Carbon capture technologies and the development of new climate-friendly cement substitutes offer great potential for use in sustainable binders.

We conduct research into sustainable cement substitutes and concrete additives

Cement substitutes and concrete additives, such as fly ash from pulverized coal combustion or granulated blast furnace slag from pig iron production, are already established in Germany. In the future, however, these will no longer be available in sufficient quantities. Potential alternatives, such as calcined clays, are therefore the focus of our scientists' research work. Our experts in the Sustainable Binders Working Group concentrate on the following topics:

  • Characterization and evaluation of clay resources with regard to their suitability as cement substitutes
  • Utilization of resource-efficient secondary raw materials containing clay to produce calcined clays
  • Further development of clay activation processes
  • Optimization of clinker-reduced cements
  • Development of alkali-activated binders based on calcined clays
  • Hydration and hardening process of binders with a low CO2 content

Calcined clays

Thermally activated, naturally occurring clays can contribute significantly to lowering the content of CO2 in cement as a reactive binder constituent. We help you identify suitable raw materials, characterize them and adjust the binder accordingly.


Cement hydration

The substitution of cement clinker with other materials has an impact on hydration. To ensure maximum strength development, the formulations need to be optimized, e.g. by adjusting the sulfate carrier.


Reactivity of cement substitutes

The intended further reduction of the clinker content in cement and the elimination of established substitutes will make cement compositions much more diverse in the future. As a result, it will become increasingly important to test the reactivity of cement constituents.


Clay mineralogy

The properties of clays in building materials are determined by their mineralogical composition. This applies both to the production of ceramic building materials and to their use as calcined clays in cement.