Constructing heterojunction interface of Co_(3)O_(4)/TiO_(2) for efficiently accelerating acetaminophen degradation via photocatalytic activation of sulfite

Achieving efficient degradation of organic pollutants via activation of sulfite is meaningful but challenging.Herein,we have constructed a heterogeneous catalyst system involving Co_(3)O_(4) and TiO_(2) nanoparticles to form the p-n heterojunction(Co_(3)O_(4)/TiO_(2)) to degrade acetaminophen(ACE) through photocatalytic activation of sulfite.Specifically,X-ray photoelectron spectroscopy analysis and theoretical calculations provide compelling evidence of electron transfer from Co_(3)O_(4) to TiO_(2) at the heterointerface.The interfacial electron redistribution of Co_(3)O_(4)/TiO_(2) tunes the adsorption energy of HSO_(3)^(-)/SO_(3)^(2-) in sulfite activation process for enhanced the catalytic activity.Owing to its unique heterointerface,the degradation efficiency of ACE reached 96.78%within 10 min.The predominant active radicals were identified as ·OH,h^(+),and SO_(x)^(·-) through radical quenching experiments and electron spin resonance capture.Besides,the possible degradation pathway was deduced by monitoring the generated intermediate products.Thereafter,the enhanced roles of well-engineered compositing interface in photocatalytic activation of sulfite for complete degradation of ACE were unveiled that it can improve light absorption ability,facilitate the generation of active species,and optimize reactive pathways.Considering that sulfite is a waste from flue gas desulfurization process,the photocatalytic activation of sulfite system will open up new avenues of beneficial use of air pollutants for the removal of pharmaceutical wastewater.

Selenium uptake and simultaneous catalysis of sulfite oxidation in ammonia-based desulfurization

Accelerating the(NH_4)_(2)SO_(3) oxidation gives rise to the reclaiming of byproduct, while there are secondary environmental risks from reduction of the coexisted selenium species by sulfite. In this study, a bi-functional Co-SBA-15-SH, were synthesized through Co impregnation and sulfhydryl(-SH) decoration, which can simultaneously uptake Se and accelerate sulfite oxidation efficiently. Meanwhile, the adsorption kinetics and migration mechanism of Se species were revealed through characterization and density functional calculations, with maximum adsorption capacity of 223 mg/g. The inhibition of Se~0 re-emission and poisonous effect of Se on sulfite oxidation was also investigated. Using the findings of this study, the ammonia desulfurization can be improved by enabling purification of the byproduct and lowering the toxicity of effluent by removing toxic pollutants.