Development and Optimization of a Nanocomposite Gel Foam for Inhibiting Coal Spontaneous Combustion

Abstract

ABSTRACT A nanocomposite gel foam inhibitor was made by grafting tea polyphenol onto sodium polyacrylate through the graft polymerization reaction, which was then combined with graphene oxide and a foaming agent. Response surface analysis was used to optimize the ratio to improve the water absorption of the inhibitor. The microstructure of the inhibitor was studied using X-ray diffraction and Fourier-transform infrared spectroscopy. The anti-spontaneous combustion performance of the nano-composite gel foam was tested through a leakage wind plugging experiment and a thermogravimetric experiment. The results show that the optimal additions of graphene, tea polyphenol, and potassium persulfate were 0.76%, 2.806%, and 0.727% of acrylic acid, respectively. The ultimate pressures of the gel foam before and after fully forming the gel were 0. 26 kPa and 0. 736 kPa, respectively, which satisfies the demand for leakage wind plugging in a coal mine. The critical temperature and dry cracking temperature of the gel foam were 112.4°C and 201.0°C, respectively, and the quality of the oxygen-absorbing and weight-gaining stage were almost unincreased. The gel foam showed good water retention, oxygen barrier, and antioxidant properties and can play a significant role in inhibiting the coal spontaneous combustion.