CO ₂ green technologies, such as methanation, reverse water-gas shift (rWGS), and dry reforming of methane (DRM) in CO ₂ capture and direct utilization process are developed using Ni/CaO catal-sorbents.

A Ni/CaO catal-sorbent could be used to reduce the required thermal energy by converting the captured CO₂ to CH₄ under H₂ at temperatures lower than those required for conventional decarbonation.

The sensing behavior of SnO₂-based thick film gas sensors in a flow system in the presence of a very low concentration (ppb level) of chemical agent simulants such as acetonitrile, dipropylene glycol methyl ether (DPGME), dimethyl methylphosphonate (DMMP), and dichloromethane (DCM) was investigated. Commercial SnO₂ [SnO₂(C)] and nano-SnO₂ prepared by the precipitation method [SnO₂(P)] were used to prepare the SnO₂ sensor in this study. In the case of DCM and acetonitrile, the SnO₂(P) sensor showed higher sensor response as compared with the SnO₂(C) sensors. In the case of DMMP and DPGME, however, the SnO₂(C) sensor showed higher responses than those of the SnO₂(P) sensors. In particular, the response of the SnO₂(P) sensor increased as the calcination temperature increased from 400 °C to 800 °C. These results can be explained by the fact that the response of the SnO₂-based gas sensor depends on the textural properties of tin oxide and the molecular size of the chemical agent simulant in the detection of the simulant gases (0.1–0.5 ppm).

In South Korea, where there are no resources such as natural gas or crude oil, research on alternative fuels has been actively conducted since the 1990s. The research on synthetic oil is subdivided into Coal to Liquid (CTL), Gas to Liquid (GTL), Biomass to Liquid (BTL), etc., and was developed with the focus on catalysts, their preparation, reactor types, and operation technologies according to the product to be obtained. In Fischer–Tropsch synthesis for synthetic oil from syngas, stability, CO conversion rate, and product selectivity of catalysts depends on the design of their components, such as their active material, promoter, and support. Most of the developed catalysts were Fe- and Co-based catalysts and were developed in spherical and cylindrical shapes according to the reactor type. Recently, hybrid catalysts in combination with cracking catalysts were developed to control the distribution of the product. In this review, we survey recent studies related to the design of catalysts for production of light hydrocarbons and middle distillates, including hybrid catalysts, encapsulated core–shell catalysts, catalysts with active materials with well-organized sizes and shapes, and catalysts with shape- and size-controlled supports. Finally, we introduce recent research and development (R&D) trends in the production of light hydrocarbons and middle distillates and in the catalytic processes being applied to the development of catalysts in Korea.

Highly efficient CO and syngas production in a cyclic system was proposed using coke-promoted Ni/CaO (C-Ni/CaO) catal-sorbent. The C-Ni/CaO exhibited high CO production in CO ₂ conversion and syngas production in CH ₄ conversion step, respectively.

The effects of the SnO₂ pore size and metal oxide promoters on the sensing properties of SnO₂-based thick film gas sensors were investigated to improve the detection of very low H₂S concentrations (<1 ppm). SnO₂ sensors and SnO₂-based thick-film gas sensors promoted with NiO, ZnO, MoO₃, CuO or Fe₂O₃ were prepared, and their sensing properties were examined in a flow system. The SnO₂ materials were prepared by calcining SnO₂ at 600, 800, 1,000 and 1,200 °C to give materials identified as SnO₂(600), SnO₂(800), SnO₂(1000), and SnO₂(1200), respectively. The Sn(12)Mo5Ni3 sensor, which was prepared by physically mixing 5 wt% MoO₃ (Mo5), 3 wt% NiO (Ni3) and SnO₂(1200) with a large pore size of 312 nm, exhibited a high sensor response of approximately 75% for the detection of 1 ppm H₂S at 350 °C with excellent recovery properties. Unlike the SnO₂ sensors, its response was maintained during multiple cycles without deactivation. This was attributed to the promoter effect of MoO₃. In particular, the Sn(12)Mo5Ni3 sensor developed in this study showed twice the response of the Sn(6)Mo5Ni3 sensor, which was prepared by SnO₂(600) with the smaller pore size than SnO₂(1200). The excellent sensor response and recovery properties of Sn(12)Mo5Ni3 are believed to be due to the combined promoter effects of MoO₃ and NiO and the diffusion effect of H₂S as a result of the large pore size of SnO₂.