Effect of nanoparticles on properties of geopolymers designed for well cementing applications

Recently the focus of the oil and gas industry is to find the alternative material for well barrier applications. Geopolymers are among the suggested materials, which could be used in the future to solve the well integrity issues rooted by the properties of Portland cement. Previous study with rock-based geopolymer indicates the potential of geopolymer to be used as a barrier material. However, there are still some shortcomings of geopolymer material, which need to be improved to make it a possible option for well cementing applications. This study aims to improve the properties of the geopolymer. Al2O3 and multi walled carbon nanotubes functionalized with hydroxyl group (MWCNT-OH) nanomaterials were used to study their effect on rheological, filtration loss, and mechanical properties of the geopolymer. Moreover, the effect of nanomaterials on the setting time and microstructure of the geopolymer has been studied. Results obtained from this work indicate that, nanomaterials-based geopolymers have better mechanical properties and setting time compared to the neat geopolymer. Addition of nanomaterials produced a more ductile structure with higher compressive and tensile strengths. Microstructure and element analysis confirmed the formation of a more compact and dense structure with the presence of MWCNT-OH and Al2O3 throughout the structure of the geopolymer.