Facile fabrication of porous Fe@C nanohybrids from natural magnetite as excellent Fischer-Tropsch catalysts

Green light enhanced the photostability and catalytic performance of fatty acid photodecarboxylase

Green light was documented to improve the photostability of fatty acid photodecarboxylase from Chlorella variabilis (CvFAP). Compared to blue light, green light increased the pentadecane yield by 27.6% and improved the residual activity of CvFAP to 5.9-fold after the preillumination. Kinetics and thermodynamics indicated that blue light facilitated a high CvFAP activity.

Single-Phase θ-Fe3C Derived from Prussian Blue and Its Catalytic Application in Fischer-Tropsch Synthesis

Elucidation of the intrinsic catalytic principle of iron carbides remains a substantial challenge in iron-catalyzed Fischer-Tropsch synthesis (FTS), due to possible interference from other Fe-containing species. Here, we propose a facile approach to synthesize single-phase θ-Fe3C via the pyrolysis of a molecularly defined Fe-C complex (Fe4[Fe(CN)6]3), thus affording close examination of its catalytic behavior during FTS. The crystal structure of prepared θ-Fe3C is unambiguously verified by combined XRD and MES measurement, demonstrating its single-phase nature. Strikingly, single-phase θ-Fe3C exhibited excellent selectivity to light olefins (77.8%) in the C2-C4 hydrocarbons with less than 10% CO2 formation in typical FTS conditions. This strategy further succeeds with promotion of Mn, evident for its wide-ranging compatibility for the promising industrial development of catalysts. This work offers a facile approach for oriented preparation of single-phase θ-Fe3C and provides an in-depth understanding of its intrinsic catalytic performance in FTS.

Direct Construction of K-Fe3C@C Nanohybrids Utilizing Waste Biomass of Pomelo Peel as High-Performance Fischer–Tropsch Catalysts

As the only renewable organic carbon source, abundant biomass has long been established and developed to mass-produce functionalized carbon materials. Herein, an extremely facile and green strategy was executed for the first time to in situ construct K-Fe3C@C nanohybrids directly by one-pot carbonizing the pomelo peel impregnated with Fe(NO3)3 solutions. The pyrolytically self-assembled nanohybrids were successfully applied in Fischer–Tropsch synthesis (FTS) and demonstrated high catalytic performance. Accordingly, the optimized K-Fe3C@C catalysts revealed excellent FTS activity (92.6% CO conversion) with highlighted C5+ hydrocarbon selectivity of 61.3% and light olefin (C2-4=) selectivity of 26.0% (olefin/paraffin (O/P) ratio of 6.2). Characterization results further manifest that the high performance was correlated with the in situ formation of the core-shell nanostructure consisting of Fe3C nanoparticles enwrapped by graphitized carbon shells and the intrinsic potassium promoter originated in pomelo peel during high-temperature carbonization. This work provided a facile approach for the low-cost mass-fabrication of high-performance FTS catalysts directly utilizing waste biomass without any chemical pre-treatment or purification.