The crystal engineering of metal oxide supports aims to enhance the performance of precious metal catalysts in semi-volatile organic compounds (SVOCs). Di (2-ethylhexyl) phthalate (DEHP) as one of the representative SVOCs in indoor environments, has become a research hotspot in recent years. For the catalytic oxidation of DEHP, Pt/TiO 2 catalysts were prepared on supports of TiO 2 with different crystalline phases (mixed phase (P25), anatase, and rutile). P25 exhibits a higher PtO x content due to its unique mixed crystalline phase, giving the best catalytic performance of the synthesized catalyst through light, thermal and photothermal catalytic experiments. The degradation of DEHP is optimized by a combination of photocatalysis and thermal catalysis. The intermediates and degradation pathways were analyzed through GC-MS and other characterization methods, and the possible degradation pathways were schematically studied. This work provides the possibility to rationalize the design of photothermal catalysts for SVOC removal.
Xia Li,Jianpeng Li,Sijia Hao,Ailing Han,Yayu Yang,Guozhen Fang,Jifeng Liu,Shuo Wang
Di(2-ethylhexyl) phthalate (DEHP), the most abundantly used plasticizer, was considered to be a hazardous chemical that was difficult to be degraded naturally. In this study, inspired by the “catalytic triad’’ in serine proteases, an enzyme mimic material was developed by combining the proteases’s active sites of serine, histidine and aspartate (S-H-D) with the self-assembling sequence of LKLKLKL and the aromatic group of fluorenylmethyloxycarbonyl (Fmoc). By mixing the monomer of peptides containing separate S, H and D residues with a ratio of 2:1:1, the enzyme mimics were found to co- assemble into nanofibers (Co-HSD) and showed the highest activity towards DEHP degradation because of the synergistic effects of active sites, orderly secondary structure and stable molecular conformation. To further improve ability and applicability, the high active mimetic enzyme was immobilized onto regenerated cellulose (RC) membranes for DEHP degradation in a continuous recycling mode. The RC membranes were first functionalized by the NaIO 4 oxidation method to form aldehyde groups and then conjugated with the enzyme mimics via Schiff-base reaction. As a biocatalytic membrane, this membrane could not only effectively degrade DEHP, but also showed good stability, thus establishing a promising biomaterial for large scale biodegradation of DEHP in water decontamination and liquid food depollution.
危险品化学品经营许可证（带存储）