Design of Reduction Process of SnO2 by CH4 for Efficient Sn Recovery

We design a novel method for the CH 4 reduction of SnO 2 for the efficient recovery of Sn from SnO 2 through a study combining theory and experiment. The atomic-level process of CH 4 -SnO 2 interaction and temperature-dependent reduction behavior of SnO 2 were studied with a combination of a multi-scale computational method of thermodynamic simulations and density functional theory (DFT) calculations. We found that CH 4 was a highly efficient and a versatile reducing agent, as the total reducing power of CH 4 originates from the carbon and hydrogen of CH 4 , which sequentially reduce SnO 2 . Moreover, as a result of the CH 4 reduction of SnO 2 , a mixture of CO and H 2 was produced as a gas-phase product (syngas). The relative molar ratio of the produced gas-phase product was controllable by the reduction temperature and the amount of supplied CH 4 . The laboratory-scale experimental study confirmed that CH 4 actively reduces SnO 2 , producing 99.34% high-purity Sn and H 2 and CO. Our results present a novel method for an efficient, green, and economical recycling strategy for Sn with economic value added that is held by the co-produced clean energy source (syngas).