Polycondensation of pyrrole and benzaldehyde catalyzed by Maghnite–H+

Cu/Biochar Bifunctional Catalytic Removal of COS and H2S:H2O Dissociation and CuO Anchoring Enhanced by Pyridine N

Economic and environmentally friendly strategies are needed to promote the bifunctional catalytic removal of carbonyl sulfide (COS) by hydrolysis and hydrogen sulfide (H2S) by oxidation. N doping is considered to be an effective strategy, but the essential and intrinsic role of N dopants in catalysts is still not well understood. Herein, the conjugation of urea and biochar during Cu/biochar annealing produced pyridine N, which increased the combined COS/H2S capacity of the catalyst from 260.7 to 374.8 mg·g-1 and enhanced the turnover frequency of H2S from 2.50 × 10-4 to 5.35 × 10-4 s-1. The nucleophilic nature of pyridine N enhances the moderate basic sites of the catalyst, enabling the attack of protons and strong H2O dissociation. Moreover, pyridine N also forms cavity sites that anchor CuO, improving Cu dispersion and generating more reactive oxygen species. By providing original insight into the pyridine N-induced bifunctional catalytic removal of COS/H2S in a slightly oxygenated and humid atmosphere, this study offers valuable guidance for further C═S and C-S bond-breaking in the degradation of sulfur-containing pollutants.

Synthesis of Copolymer from 1,3,5-Trioxane and -Caprolactone Catalysed by Treated Bentonite as Eco-Catalyst

This study presents a novel green method for copolymerizing 1,3,5-trioxane (TOX) with ε caprolactone (CL). This technique uses Maghnite-H+ (Mag-H+) as a bulk green catalyst. Various techniques were used to confirm the structure of the resulting copolymer. The influencing factors on the copolymerization reaction were also studied. The results show that the best copolymer yield (46.3 %) was obtained via bulk copolymerization at a temperature of 353 K for a reaction time of 8 h.