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Journal of Environmental Sciences 2006年第4期18卷 660-664页

作者： REN Guang-meng SUN De-zhi CHUNG Jong Shik School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China Department of Chemical Engineering Pohang University of Science and Technology Pohang 790-784 South Korea

An investigation on the process of ozone combined with hydrogen peroxide and ultraviolet radiation has been carried out in order to establish the kinetics for photochemical oxidation of polyacrylamide （PAM） in aqueous solution. Effects of operating parameters, including initial PAM concentration, dosages of ozone and hydrogen peroxide, UV radiation and pH value on the photochemical oxidation of PAM, have been studied. There was an increase in photochemical oxidation rate of PAM with increasing of dosages of 03, H2O2 and ultraviolet radiation. Upon increasing of the initial PAM concentration, the photochemical oxidation rate of PAM decreased. Slight effect of pH value on the photochemical oxidation rate of PAM was observed in the experiments. The kinetics equation for the photochemical oxidation of PAM by the system has been established.

关键词： photochemical oxidation polyacrylamide kinetics ozone/hydrogen peroxide/ultraviolet radiation

Assessing the role of mineral particles in the atmospheric photooxidation of typical carbonyl compound

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Journal of Environmental Sciences 2021年第7期33卷 56-63页

作者： Yongpeng Ji Xingyu Chen Yuqi Xiao Yuemeng Ji Weina Zhang Jiaxin Wang Jiangyao Chen Guiying Li Taicheng An Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and HealthInstitute of Environmental Health and Pollution controlKey Laboratory of City Cluster Environmental Safety and Green developmentSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Mineral particles are ubiquitous in the atmosphere and exhibit an important effect on the photooxidation of volatile organic compounds(VOCs).However,the role of mineral particles in the photochemical oxidation mechanism of VOCs remains ***,the photooxi-dation reactions of acrolein(ARL)with OH radical(OH)in the presence and absence of SiO_(2) were investigated by theoretical *** gas-phase reaction without SiO_(2) has two distinct pathways(H-abstraction and OH-addition pathways),and carbonyl-H-abstraction is the dominant *** the presence of SiO_(2),the reaction mechanism is changed,i.e.,the dominant pathway from carbonyl-H-abstraction to OH-addition to carbonyl *** energy barrier of OH-addition to carbonyl C-atom deceases 21.33 kcal/mol when SiO_(2) is *** H-atom of ARL is occupied by SiO_(2) via hydrogen bond,and carbonyl C-atom is ac-tivated by SiO_(2).Hence,the main product changes from H-abstraction product to OH-adduct in the presence of SiO_(2).The OH-adduct exhibits a thermodynamic feasibility to yield HO_(2) radical and carboxylic acid via the subsequent reactions with O_(2),with implications for O 3 formation and surface acidity of mineral particles.

关键词： photochemical oxidation Mineral particles Acrolein Reaction mechanism

Seasonal variation and size distribution of biogenic secondary organic aerosols at urban and continental background sites of China

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Journal of Environmental Sciences 2018年第9期30卷 32-44页

作者： Yanqin Ren Gehui Wang Jianjun Li Can Wu Cong Cao Jiayuan Wang Lu Zhang Fan Meng Hong Li State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi'an 710061 China. Key Laboratory of Geographic Information Science of the Ministry of Education School of Geographic Sciences East China Normal UniversityShanghai 200041 China Center of Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China University of Chinese Academy of Sciences Beijin9 100049 China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012 China

Size-resolved biogenic secondary organic aerosols （BSOA） derived from isoprene and monoterpene photooxidation in Qinghai Lake, Tibetan Plateau （a continental background site） and five cities of China were measured using gas chromatography/mass spectrometry （GC/MS）. Concentrations of the determined BSOA are higher in the cities than in the background and are also higher in summer than in winter. Moreover, strong positive correlations （R^2 = 0.44-0.90） between BSOA and sulfate were found at the six sites, suggesting that anthropogenic pollution （i.e., sulfate） could enhance SOA formation, because sulfate provides a surface favorable for acid-catalyzed formation of BSOA. Size distribution measurements showed that most of the determined SOA tracers are enriched in the fine mode （〈3.3 μm） except for cis-pinic and cis-pinonic acids, both presented a comparable mass in the fine and coarse （〉3.3 μm） modes, respectively. Mass ratio of oxidation products derived from isoprene to those from monoterpene in the five urban regions during summer are much less than those in Qinghai Lake region. In addition, in the five urban regions relative abundances of monoterpene oxidation products to SOA are much higher than those of isoprene. Such phenomena suggest that BSOA derived from monoterpenes are more abundant than those from isoprene in Chinese urban areas.

关键词： Biogenic secondary organic aerosols photochemical oxidation Seasonal and spatial variations Size distribution Sulfate

Photoassisted fenton oxidation of refractory organics in UASB-pretreated leachate

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Journal of Environmental Sciences 2002年第3期14卷 388-392页

作者： LauIWC WangP CentreforEnvironmentalEngineeringResearch DepartmentofCivilEngineeringTheUniversityofHongKongPokfulamRoadHongKong DepartmentofEnvironmentalSci9enceandEngineering HarbinInstitute

Nearly 91% of organic pollutants in Hong Kong leachate could be effectively removed by the UASB(upflow anaerobic sludge blanket) process followed by the fenton coagulation. The COD (chemical oxygen demand) of leachate was lowered from an average of 5620 mg/L to 1910 mg/L after the UASB treatment at 37℃, and was further lowered to 513 mg/L after fenton coagulation. The remaining refractory residues could be further removed by photochemical oxidation with the addition of H 2O 2. The BOD/COD ratio was greatly increased from 0.062 to 0.142, indicating the biodegradability of organic residues was improved. The photochemical oxidation for the fenton\|coagulation supernatant was most effective at pH 3\_4, with the addition of 800 mg/L of H 2O 2, and UV radiation time of 30 minutes. The final effluent contained only 148 mg/L of COD, 21 mg/L of BOD(biochemical oxygen demand) and 56 mg/L of TOC (total organic carbon).

关键词： biodegradability fenton landfill leachate photochemical oxidation UASB

UV-catalytic treatment of spent caustic from ethene plant with hydrogen peroxide and ozone oxidation

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Journal of Environmental Sciences 2004年第2期16卷 272-275页

作者： YUZheng-zhe SUNDe-zhi LIChang-hai SHIPeng-fei DUANXiao-dong SUNGuo-rong ResearchCenterforEco-EnvironmentalSciences CASBeijing100085China. DepartmentofEnvironmentalScienceandEngineering HarbinInstituteofTechnologyHarbin150001China

The performance of UV/H 2O 2, UV/O 3 and UV/H 2O 2/O 3 oxidation systems for treating spent caustic from an ethylene plant was investigated. In UV/H 2O 2 system, with the increase of H 2O 2 dosage, removal efficiencies of COD and the ratio of biochemical oxygen demand(BOD) to chemical oxygen demand(COD) of the effluent were increased and a better performance was obtained than the H 2O 2 system alone. In UV/H 2O 2 system, removal efficiency of COD reach 68% under the optimum condition, and BOD/COD ratio was significantly increased from 0 22 to 0 52. In UV/O 3 system, with the increase of O 3 dosage, removal efficiency of COD and BOD/COD ratio were increased, and a better performance was obtained than the O 3 system alone. Under the optimum condition, removal efficiency of COD was 54%, and BOD/COD ratio was significantly increased from 0 22 to 0 48. In UV/H 2O 2/O 3 system, COD removal efficiency was found to be 22.0% higher than UV/O 3 system.

关键词： spent caustic photochemical oxidation UV/O 3 system UV/H 2O 2 system UV/H 2O 2/O 3 system