Effective methane biodegradation through in situ coupling with methanotroph and HK@SB-1 MOFs

Abstract

Methane is a primary greenhouse gas that poses significant risks to the safety of coal mine operations. Microbial methane degradation offers a sustainable and environmentally friendly solution with considerable potential for development. However, the slow mass transfer rate often hinders the process, necessitating improvements to enhance methane degradation efficiency. This research introduces an innovative in situ coupling strategy that leverages methanotrophic bacteria's high selectivity and adsorbents' rapid adsorption capabilities. Initially, the dominant strain of methane-degrading bacteria was isolated from rice paddies. Following this, the strain was characterized as methanotroph and its physicochemical properties were investigated to optimize its gas-degrading efficiency. Subsequently, the synthesis of HKUST-1@SBA-16 composites was achieved by incorporating mesoporous silica SBA-16 into HKUST-1, resulting in materials with superior stability and adsorption characteristics. Subsequently, accelerated methane biodegradation was achieved through the in situ coupling of the methanotroph T2 with the HKUST-1@SBA-16 composite. Under optimal conditions, the methane degradation rate within the HKUST-1@SBA-16-T2 system reached 98.65%. This study introduces an innovative approach to the efficacious mitigation of methane emissions achieved by integrating natural microbial processes with metal–organic frameworks (MOFs). This comprehensive strategy is important for preventing coal mine gas outbursts, and this is of great significance and pioneering in the efficient and selective removal of methane using natural bacteria combined with artificial materials.

Keywords: Methanotrophs; MOFs; Methane degradation; Adsorbent; Microbial degradation.