Synthesis and characterization of a penetrating and pre-wetting agent for coal seam water injection

Coal seam water injection, as an indispensable process in underground mining, is of great significance to the treatment of dust hazard in working face. However, the permeability of water in the coal seam is unsatisfactory due to hydrophobic properties of coal and many other factors. Here we synthesized a water injection additive with stellate structure by modified beta-cydodextrin. The molecular structure characteristics of the product were analyzed by FUR, XRD and TG-DTG-DSC. The permeability and wettability of materials, which are closely related to water injection were tested. The contact angle of 0.1% product solution was only 25 degrees. Moreover, combined with the characteristics of molecular structure and the effects, the principle of action was explained. And the optimum reaction conditions were determined. Alter performance testing, the synthesized material has stronger penetrating and pre-wetting ability than common surfactants, and the mechanism of its action was explained based on the molecular characteristics of the material. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

A water injection additive with stellate structure was synthesized in this study, and its molecular structure characteristics and effects on water permeability and wettability were analyzed. The experimental results showed that the additive has good penetrating and pre-wetting ability, with the mechanism of action explained clearly, and the optimum reaction conditions determined.