Hydrotalcite-derived Ni-LDO catalysts via new approach for enhanced performances in CO2 catalytic reduction

In this work, hydrotalcite-derived new Ni-LDO catalysts were synthesized via sequenced precipitation, for CO2 catalytic reduction to synthetic natural gas (SNG) with high performances, while the traditional sample via coprecipitation was prepared and measured as the comparison. By regulating precipitation procedure, a significant performance enhancement was attained, in which the CO2 conversion rate per gram nickel was 7-times higher than that of the conventional comparison, at the temperature of 573 K and atmospheric pressure. In addition, the desired product selectivity is up to 99%. Structural characterizations proved that the as-synthesized catalysts showed layered meso-porous properties. An increasing Ni particle size and higher coverage of medium strong basic sites was observed over the optimized catalyst sample prepared when part of Mg2+ and Al3+ were precipitated at first step. Catalyst surface nickel enrichment and promoted reducibility were also achieved when using sequenced precipitation. This work achievements provided a new route for surface nickel enrichment of much more active hydrotalcite-derived Ni-LDO layered catalysts for enhanced performances.

Automated summary

This work presents the synthesis of hydrotalcite-derived Ni-LDO catalysts using sequenced precipitation for CO2 catalytic reduction to SNG. The performance enhancement achieved through regulating precipitation procedure resulted in a 7-fold increase in CO2 conversion rate per gram nickel compared to the traditional coprecipitation method. The optimized catalysts showed layered meso-porous properties and an increase in Ni particle size with higher coverage of medium strong basic sites. Sequential precipitation also led to surface nickel enrichment and promoted reducibility of the catalysts.