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 β-cyclodextrin. The molecular structure characteristics of the product were analyzed by FTIR, 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°. Moreover, combined with the characteristics of molecular structure and the effects, the principle of action was explained. And the optimum reaction conditions were determined. After 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.