Hexagonal boron nitride: A metal-free catalyst for deep oxidative desulfurization of fuel oils
Peiwen Wu, Linjie Lu, Jing He, Linlin Chen, Yanhong Chao, Minqiang He, Fengxia Zhu, Xiaozhong Chu, Huaming Li, Wenshuai Zhu
Abstract
Oxidative desulfurization (ODS) has been proved to be an efficient strategy for the production of clean fuel oil. Numerous metal-based materials have been employed as excellent ODS catalysts, but being hindered by their high-cost and potential secondary pollution. In this work, we employed graphene analogous hexagonal boron nitride (h-BN) as a metal-free catalyst for ODS with hydrogen peroxide (H2O2) as the oxidant. The h-BN catalyst was characterized and proved to be a few-layered structure with relatively high specific surface areas. The h-BN catalyst showed a 99.4% of sulfur removal in fuel oil under the optimized reaction conditions. Besides, the h-BN can be recycled for 8 times without significant decrease in the catalytic performance. Detailed mechanism analysis found that it is the boron radicals in h-BN activated H2O2 to generate ·OH species, which can readily oxidize sulfides to corresponding sulfones for separation. This work would provide another choice in choosing metal-free catalysts for ODS.