A new solid acid catalyst SO42-MoO3TiO2 was prepared.FT-IR data had indicted that the surface of the catalyst had strong acidic centers.FTIR spectra of pyridine absorbed on the surface showed that th...A new solid acid catalyst SO42-MoO3TiO2 was prepared.FT-IR data had indicted that the surface of the catalyst had strong acidic centers.FTIR spectra of pyridine absorbed on the surface showed that the catalyst had Bronsted acid site.The catalyst had high catalytic activity and excellent selectivity in esterification,acetalation and ketal formation as well as no corrosion to the facilities.The catalyst was an enviormentally friendly catalyst.展开更多
制备了 SO_42-/La_2O_3~TiO_2-HZSM-5超强酸催化剂,用于催化癸二酸和正丁醇的酯化反应,研究了制备条件对催化剂性能的影响。结果表明:La3+浸渍浓度为0.07 mol/L,经110℃烘干后于500℃焙烧3 h 所得催化剂的活性较好。用正交实验...制备了 SO_42-/La_2O_3~TiO_2-HZSM-5超强酸催化剂,用于催化癸二酸和正丁醇的酯化反应,研究了制备条件对催化剂性能的影响。结果表明:La3+浸渍浓度为0.07 mol/L,经110℃烘干后于500℃焙烧3 h 所得催化剂的活性较好。用正交实验法考察了酯化反应的影响因素,最佳实验条件为:正丁醇/癸二酸(物质的量比)=4:1,反应时间3 h,催化剂用量1.5%(质量分数),酯化率可达98.7%。该催化剂具有良好的重复使用和再生能力。展开更多
Oxygen vacancy engineering in heterogeneous catalysts has attracted considerable interest for peroxymonosulfate(PMS)activation.In this study,nano-Co3O4-encapsulated montmorillonite catalysts with tunable oxygen ...Oxygen vacancy engineering in heterogeneous catalysts has attracted considerable interest for peroxymonosulfate(PMS)activation.In this study,nano-Co3O4-encapsulated montmorillonite catalysts with tunable oxygen vacancy(OV)concentrations(denoted as Co3O4−Mt-xOV,x=2,4,6)were synthesized for enhanced PMS activation.These OV defects not only modulate the electronic structure of Co3O4but also strengthen PMS and contaminant adsorption.The optimized Co3O4−Mt-xOV/PMS system exhibited exceptional ofloxacin(OFL)degradation efficiency,achieving 2.74–3.43-fold enhancement over OV-free Co3O4−Mt.Density functional theory calculations and experimental studies revealed that the performance improvement stemmed from OV formation,which synergistically enhanced redox pair cycling,strengthened PMS adsorption,and promoted active species generation during electron transfer.Further studies demonstrated that OV sites selectively drive PMS decomposition to generate high-valent cobalt-oxo species(Co(Ⅳ)=O)and singlet oxygen(1O2)as the dominant reactive species for OFL oxidation.The in-depth investigation into the catalytic mechanism revealed that the Co(Ⅳ)=O species facilitated O2•−generation in surpassing the reaction energy barrier,which subsequently converted to1O2.This non-radical pathway endowed the system with robust anti-interference capability against complex water matrices.The critical role of OV in PMS activation was mechanistically confirmed through experimental and theoretical analyses.Furthermore,Co3O4−Mt-4OV demonstrated outstanding chemical stability and recyclability,highlighting its practical potential.This work provides fundamental insights into vacancy defect engineering for advanced PMS activation and offers strategic guidance for designing high-performance catalysts.展开更多
摘要A new solid acid catalyst SO42-MoO3TiO2 was prepared.FT-IR data had indicted that the surface of the catalyst had strong acidic centers.FTIR spectra of pyridine absorbed on the surface showed that the catalyst had Bronsted acid site.The catalyst had high catalytic activity and excellent selectivity in esterification,acetalation and ketal formation as well as no corrosion to the facilities.The catalyst was an enviormentally friendly catalyst.
基金supported by National Natural Science Foundation of China(Nos.22476116,52074176,52400090)Natural Science Foundation of Shandong Province(Nos.ZR2024ME156,ZR2024QB138)Qingdao Natural Science Foundation(No.24-4-4-zrjj-70-jch).
摘要Oxygen vacancy engineering in heterogeneous catalysts has attracted considerable interest for peroxymonosulfate(PMS)activation.In this study,nano-Co3O4-encapsulated montmorillonite catalysts with tunable oxygen vacancy(OV)concentrations(denoted as Co3O4−Mt-xOV,x=2,4,6)were synthesized for enhanced PMS activation.These OV defects not only modulate the electronic structure of Co3O4but also strengthen PMS and contaminant adsorption.The optimized Co3O4−Mt-xOV/PMS system exhibited exceptional ofloxacin(OFL)degradation efficiency,achieving 2.74–3.43-fold enhancement over OV-free Co3O4−Mt.Density functional theory calculations and experimental studies revealed that the performance improvement stemmed from OV formation,which synergistically enhanced redox pair cycling,strengthened PMS adsorption,and promoted active species generation during electron transfer.Further studies demonstrated that OV sites selectively drive PMS decomposition to generate high-valent cobalt-oxo species(Co(Ⅳ)=O)and singlet oxygen(1O2)as the dominant reactive species for OFL oxidation.The in-depth investigation into the catalytic mechanism revealed that the Co(Ⅳ)=O species facilitated O2•−generation in surpassing the reaction energy barrier,which subsequently converted to1O2.This non-radical pathway endowed the system with robust anti-interference capability against complex water matrices.The critical role of OV in PMS activation was mechanistically confirmed through experimental and theoretical analyses.Furthermore,Co3O4−Mt-4OV demonstrated outstanding chemical stability and recyclability,highlighting its practical potential.This work provides fundamental insights into vacancy defect engineering for advanced PMS activation and offers strategic guidance for designing high-performance catalysts.