In-situ preparation of ZnO-based activated carbon desulfurizer from low-rank coal

Dispersing the metal oxide active component on the porous carrier by impregnation and loading is a common method for preparing highly active metal oxide desulfurizers. However, due to the decrease of porosity of the carrier due to the loading of active components, the desulfurization capacity of active components cannot be fully utilized. In this study, cheap low-rank coal was directly used as raw material. After pretreatment, zinc nitrate was added into the coal to prepare ZnO based activated carbon desulfurizer at room temperature in one step through physical-chemical activation method. The preparation of activated carbon and the loading of active components were completed in one step. The effects of zinc nitrate immersion amount, activation temperature and activation time on desulfurization performance of desulfurizer were studied. The results showed that when the immersion amount was 20%(mass), the activation temperature was 850℃, and the activation time was 1 h, the breakthrough time of desulfurizer was 210 min, and its sulfur capacity was 71.4 mg/g. Its desulfurization performance was 5.3 times that of commercial activated carbon supported ZnO desulfurizer under the same experimental conditions. The high desulfurization performance is mainly attributed to its developed mesoporous pores, which is not only conducive to mass transfer, but also beneficial to the storage of sulfide products. © 2021, Editorial Board of CIESC Journal. All right reserved.