Design of Reduction Process of SnO by CH for Efficient Sn Recovery.

We design a novel method for the CH reduction of SnO for the efficient recovery of Sn from SnO through a study combining theory and experiment. The atomic-level process of CH-SnO interaction and temperature-dependent reduction behavior of SnO were studied with a combination of a multi-scale computational method of thermodynamic simulations and density functional theory (DFT) calculations. We found that CH was a highly efficient and a versatile reducing agent, as the total reducing power of CH originates from the carbon and hydrogen of CH, which sequentially reduce SnO. Moreover, as a result of the CH reduction of SnO, a mixture of CO and H 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. The laboratory-scale experimental study confirmed that CH actively reduces SnO, producing 99.34% high-purity Sn and H 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).