Construction of BiOBr0.5Cl0.5 heterojunctions for photocatalytic treatment of waste drilling fluid in oilfield

Abstract

Abstract Drilling fluid is very essential for oil and gas drilling process. However, the treatment of the waste drilling fluid becomes an urgent issue because of the large amount and the lack in effective degradation method. Photocatalysis as an advanced strategy to solve the environmental pollution, has drawn widely attention. In this contribution, BiOBr0.5Cl0.5 heterojunctions are constructed through a hydrothermal method to act as a photocatalyst for photocatalytic degradation of waste drilling fluid. The successful construction of BiOBr0.5Cl0.5 heterojunctions is confirmed by XRD, SEM, EDS, and BET analysis and the results show that BiOBr0.5Cl0.5 is not a simple mechanical mixture. These heterojunctions in synthesis of photocatalyst is conducive to the photoactivity, which would lead to relatively high surface area and pore width in photocatalyst. It is found that photocatalytic degradation over BiOBr0.5Cl0.5 is a feasible approach for solving waste drilling fluid pollution. From the results of evaluation experiments, it can be seen that the colored materials and macromolecular organic polymers can be both degraded by BiOBr0.5Cl0.5. The presence of Br and Cl in the composite could promote the effective separation of photogenerated carriers and the construction of the active species ·O2- and ·H+, enhancing the photocatalytic activity of BiOBr0.5Cl0.5 heterojunctions. Given that the outstanding performance in degrading RhB or HPAM and the sustainability of BiOBr0.5Cl0.5, The photocatalytic offers a promising reference to the treatment of waste drilling fluid.