Biomass chemical looping gasification (BCLG) is a novel and promising technology for syngas production, in which lattice oxygen in oxygen carriers (OCs) reacts with biomass. OCs can continuously supply oxygen for biomass gasification using a redox cycle between different reactors, and the reduced OC can serve as a good catalyst for biomass tar and char cracking, improving the gasification efficiency. The notable advantages of BCLG have attracted attention around the world, particularly in China. Chinese researchers have become the major drivers of the development of BCLG technologies. The experience gained from the experimental tests of BCLG in China is valuable for the further development of BCLG. In this review, we mainly focus on the biomass feedstock, the OC, the tar yield, the reactor, and the results of the BCLG tests in Chinese studies. On the basis of those findings, we summarize the criteria for biomass and the OCs in BCLG, and potential directions for reactor development are briefly discussed. In general, the mechanism of BCLG has been investigated in many studies, and the effects of the operating conditions are relatively well-understood. However, there are still few reports on BCLG units that have potential for industrial application. The controllable composition of syngas is worthy of further investigation, and this is required for downstream utilization. Additionally, as a result of the low pollutant emission, chemical looping gasification of solid wastes might be available in the future.

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The deposition of slag from a realgar tailing mine has caused serious land degradation to those farming and mining coexisting areas. However, nanomaterial‐mediated biogeochemical arsenic cycle from arsenic‐enriched soil was severely limited. In this study, the environmental impact of graphene oxide (GO) and reduced GO (rGO) on the speciation and mobilization of Fe/As from the flooding of arsenic‐enriched soil was investigated. Regarding overall performance, rGO exhibited a more significant facilitation than GO on mediating microbial reduction of Fe(III)/As(V). The maximal levels of soluble Fe(II) and As(III) in the soil supplemented with acetate alone were 53.58 g.m−3 and 9592 mg·m−3 during the 50‐day culture period. Nearly 1.37‐fold and 1.15‐fold of As(III) levels were released when amending with rGO acetate and GO acetate. Meanwhile, approximately 1.40‐fold and 1.24‐fold of Fe(II) levels were released under the same conditions. The underlying mechanism was correlated with the interactions between graphene and microbial activities. The properties of GO have been evolved through microbial reduction and eventually exhibited characteristics similar to rGO. Additionally, the application of graphene potentially altered the compositions of the microbial community and increased the abundance of some metal‐reducing bacteria (e.g., Bacillus, Geobacter, and Desulfitobacterium), thereby favouring the dissolved organic matter bioavailability for bioreduction of Fe(III)/As(V). In addition, promotion of the electron transfer process of As(V)/Fe(III) reduction was predominantly responsible for the crucial role that rGO exhibited as a special redox‐active mediator and electrical conductor. These findings might provoke more consideration of the integrated ecological effects of graphene and evaluate their environmental impact on land degradation.