1,2,4-trichlorobenzene decomposition using non-thermal plasma technology

Non-thermal plasma(NTP)is regarded as a potential application for environmental pollution control due to its ability to remove pollutants.As a major precursor of dioxins,the influence of the parameters of 1,2,4-trichlorobenzene(TCB)decomposition using NTP technology was investigated through a series of experiments,including voltage,frequency,water content,initial concentration,flow rate,and oxygen content.The experimental results show that the energy injected into the NTP system has a positive correlation to voltage and frequency.Oxygen has the greatest influence on TCB decomposition.The optimal reaction condition was at 15 kV,1000 Hz,an initial concentration of 20 mg m^?3,a flow rate of 2 l min^?1,H2O at 4%,and O2 at 0%.Under this condition,the TCB removal efficiency could reach 92%.According to the generated product backstepping,the hydroxyl radical(·OH)plays an important role in TCB decomposition due to its strong oxidation,which participates in the dechlorination and oxidation reactions as free radicals,and the possible decomposition pathway of TCB by NTP is inferred from the identified byproducts.It is of great significance to investigate the influence of the parameters of TCB decomposition using NTP technology in order to provide references for industrial application.

Influe nee of gas atmosphere on synergistic control of mercury and dioxin by nonthermal plasma

In this paper,narrow-pulse power discharge is used to study the synergistic control of mercury and dioxins,in which 1,2,4-trichlorobenzene(TCB)was used as a dioxin analog,by using a selfdesigned experimental system.The competitive effects of NO,SO2 and HC1 on the TCB removal by non-thermal plasma are discussed.The influence of acid gas on TCB degradation is reflected in the competitive effect.NO has the greatest influence on TCB degradation efficiency.The oxidation efficiency of Hg°decreased by about 10%in all three acidic gas atmospheres,and the effect of each gas component on Hg()oxidation is complex.In the flue gas atmosphere of'acid gas+Hg°+TCB',the mechanism of the synergistic control of Hg°and TCB by the nonthermal plasma is different,which has competition and promotion relationship between each other.The contribution of various flue gas components to the results was complicated,but the overall experimental results show that the synergistic control effect of the system can continue to improve.According to the generated product backstepping,-OH plays an important role in the synergistic control of the degradation of Hg°and TCB.Through this study,we hope to provide basic research data for the collaborative control of flue gas in the incineration industry.

Efficient activation of peroxymonosulfate by hollow cobalt hydroxide for degradation of ibuprofen and theoretical study

Hollow microsphere structure cobalt hydroxide(h-Co(OH)2) was synthesized via an optimized solvothermal-hydrothermal process and applied to activate peroxymonosulfate(PMS) for degradation of a typical pharmaceutically active compound,ibuprofen(IBP).The material characterizations confirmed the presence of the microscale hollow spheres with thin nanosheets shell in h-Co(OH)2,and the crystalline phase was assigned to a-Co(OH)2.h-Co(OH)2 could efficiently activate PMS for radicals production,and 98.6% of IBP was degraded at 10 min.The activation of PMS by h-Co(OH)2 was a pHindependent process,and pH 7 was the optimum condition for the activation-degradation system.Scavenger quenching test indicated that the sulfate radical(SO4^·-) was the primary reactive oxygen species for IBP degradation,which contributed to 75.7%.Fukui index(f^-) based on density functional theory(DFT) calculation predicted the active sites of IBP molecule for SO4^·- attack,and then IBP degradation pathway was proposed by means of intermediates identification and theoretical calculation.The developed hollow Co(OH)2 used to efficiently activate PMS is promising and innovative alternative for organic contaminants removal from water and wastewater.