31 results on '"Lv, Guochun"'
Search Results
2. Zr6O8-porphyrinic MOFs as promising catalysts for the boosting photocatalytic degradation of contaminants in high salinity wastewater
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Wang, Zhiwei, Liu, Zhen, Huang, Jiaying, Chen, Yi, Su, Ruidian, He, Jinkai, Lv, Guochun, Gao, Baoyu, Zhou, Weizhi, Wang, Yan, Wang, Zhining, and Li, Qian
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- 2022
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3. Enhanced degradation of bisphenol F in a porphyrin-MOF based visible-light system under high salinity conditions
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Wang, Zhiwei, Li, Qian, Su, Ruidian, Lv, Guochun, Wang, Zhining, Gao, Baoyu, and Zhou, Weizhi
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- 2022
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4. Potential environmental fate and risk based on the hydroxyl radical-initiated transformation of atmospheric 1,2-dibromo-4-(1,2dibromoethyl)cyclohexane stereoisomers
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Wang, Ning, He, Lin, Lv, Guochun, and Sun, Xiaomin
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- 2021
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5. The molecular-level understanding of the uptake of PFOS and its alternatives (6:2 Cl-PFESA and OBS) into phospholipid bilayers
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Lv, Guochun and Sun, Xiaomin
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- 2021
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6. Mechanisms, kinetics and eco-toxicity assessment of singlet oxygen, sulfate and hydroxyl radicals-initiated degradation of fenpiclonil in aquatic environments
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Yang, Jiaoxue, Lv, Guochun, Wang, Zehua, Sun, Xiaomin, and Gao, Jian
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- 2021
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7. The properties of asphaltene at the oil-water interface: A molecular dynamics simulation
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Lv, Guochun, Gao, Fengfeng, Liu, Guokui, and Yuan, Shiling
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- 2017
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8. Mechanistic insight into the formation of aromatic organosulfates and sulfonates through sulfoxy-radical-initiated reactions in the atmospheric aqueous phase.
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Lv, Guochun, Yue, Wenjing, Wang, Zehua, Wang, Guiyin, Cheng, Zhang, Yang, Zhanbiao, Xu, Changlian, Qi, Xin, Cai, Junzhuo, and Xu, Xiaoxun
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BENZOIC acid , *AROMATIC compounds , *RADICALS (Chemistry) , *ACTIVATION energy , *AEROSOLS - Abstract
Despite monocyclic aromatic organosulfates (OSs) and sulfonates have been ubiquitously detected in aerosols, their formation processes need to be further analyzed. Monocyclic aromatic hydrocarbon reactions with sulfoxy radical are considered as the significant formation pathway of these monocyclic organosulfur compounds in recent studies, but the reaction mechanism remains unknown. In this work, we selected benzoic acid as a representative monocyclic aromatic hydrocarbon to study its reaction with SO 3 ·- and SO 4 ·- using quantum chemical calculation. The result shows that SO 4 ·- is the main initiator for benzoic acid and its anion (benzoate). And dragging an electron from benzoate (or an H atom from benzoic acid) to produce the radical C 6 H 5 COO· is the most favorable route in SO 4 ·--initiated benzoate (or benzoic acid) reactions due to the lowest activation free energies (5.14 or 5.47 kcal mol−1). In addition, the addition of SO 4 ·- to benzoate (or benzoic acid) can also occur because their activation free energies are close to the value of the most favorable route. The analysis on rate constants indicates higher pH can facilitate the formation of these OSs and sulfonates. The produced OSs and sulfonates have different characteristics: only phenyl sulfonate is formed for monocyclic aromatic sulfonates, while both phenyl sulfate and carboxyphenyl sulfate are generated for monocyclic aromatic OSs. This mechanism study can extend our understanding about the formation of monocyclic aromatic OSs and sulfonates, and provide the insight into further studies on aromatic OSs and sulfonates. [Display omitted] • SO 3 ·- cannot compete with SO 4 ·- in initial processes. • SET of benzoate and HAT of benzoic acid are the most favorable. • The C 6 H 5 COO· from the most favorable routes will produce phenyl sulfonate and OS. • RAF products of benzoate and benzoic acid is converted to two OSs. • The total apparent rate constant is positive pH-dependent. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Understanding the properties of methanesulfinic acid at the air-water interface.
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Lv, Guochun, Zhang, Heng, Wang, Zehua, Wang, Ning, Sun, Xiaomin, Zhang, Chenxi, and Li, Mei
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Abstract Methanesulfinic acid (MSIA), an organic sulfur compound, is mainly produced in the oxidation process of dimethyl sulfide in the atmosphere. The properties of MSIA at the air-water interface were studied using molecular dynamics (MD) simulations. The result shows that the lowest system free energy is located at the interface. Because the free energy difference between the interface and water phase is 3.2 kJ mol−1, the MSIA molecule can easily get out of the free energy well and travel to water phase by the thermal motion, leading to only a 21% probability of its occurrence at the interface. The MSIA molecule tends to tilt at the interface with the sulfino group (-S(O)-OH) pointing toward the water phase. The feature of hydration status at the air-water interface may be favorable to the heterogeneous oxidation of MSIA. Graphical abstract Unlabelled Image Highlights • The properties of MSIA at the air-water interface are studied using MD simulations. • The lowest free energy is located at the air-water interface. • Probability of MSIA at the interface is about 21%. • The tilted orientation at the interface is predominant. • The feature of hydration status at the interface is found. [ABSTRACT FROM AUTHOR]
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- 2019
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10. Understanding the atmospheric transformation mechanism of an emerging fluorinated alcohol (FESOH).
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Lv, Guochun, Yang, Jiaoxue, Sun, Xiaomin, Wang, Guiyin, Cheng, Zhang, Yang, Zhanbiao, Xu, Changlian, Cai, Junzhuo, and Xu, Xiaoxun
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ABSTRACTION reactions , *QUANTUM chemistry , *ALKYL radicals , *ATMOSPHERE , *ALCOHOL - Abstract
One important pathway for human exposure to per- and polyfluorinated alkyl substances (PFASs) is based on the Earth's atmosphere. Figuring out atmospheric transformation mechanism of PFASs is beneficial for understanding their effects on humans. However, the focus on the molecular-level transformation mechanism of emerging PFASs in the atmosphere still need to be improved. In this work, we used quantum chemistry calculation to study ·OH-initiated degradation mechanism of a new fluorinated alcohol (C 3 F 7 OCHFCF 2 SCH 2 CH 2 OH, abbreviated FESOH) in the presence of oxygen and nitric oxide. Three main conformers of FESOH share the similar initial mechanism that the abstraction reactions of H atom at α-C and β-C atoms are the main pathways (activation free energies of <10 kcal mol−1 at 298 K), but make different contributions to the whole FESOH degradation. Subsequent transformations starting from initial products at α-C atoms will reunite with that at β-C atoms, and the intermediate (C 3 F 7 OCHFCF 2 S·) is produced. After O 2 addition to the intermediate and the following SO 2 elimination, the alkyl radical (C 3 F 7 OCHFCF 2 ·) can undergo consecutive chain cleavage cycles to form CF 3 OH finally. The bioaccumulation evaluation shows that FESOH and its transformation products cannot be accumulated in organisms. The work is helpful for knowing the atmospheric fate of FESOH at molecular level and can provide some insight into the transformation of other PFASs in the atmosphere. [Display omitted] • Three main conformers of FESOH account for approximate 99% of all conformers. • The H-abstraction at α-C and β-C mainly occurs for ·OH-initiated FESOH degradation. • Subsequent reactions can form alkyl peroxynitrite, fluorinated aldehyde and CF 3 OH. • FESOH and its transformation products cannot be accumulated in organisms. [ABSTRACT FROM AUTHOR]
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- 2023
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11. Towards understanding the role of amines in the SO2 hydration and the contribution of the hydrated product to new particle formation in the Earth's atmosphere.
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Lv, Guochun, Nadykto, Alexey B., Sun, Xiaomin, Zhang, Chenxi, and Xu, Yisheng
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ALIPHATIC amines , *SULFUR dioxide , *HYDRATION , *GAS phase reactions , *ACTIVATION energy - Abstract
By theoretical calculations, the gas-phase SO 2 hydration reaction assisted by methylamine (MA) and dimethylamine (DMA) was investigated, and the potential contribution of the hydrated product to new particle formation (NPF) also was evaluated. The results show that the energy barrier for aliphatic amines (MA and DMA) assisted SO 2 hydration reaction is lower than the corresponding that of water and ammonia assisted SO 2 hydration. In these hydration reactions, nearly barrierless reaction (only a barrier of 0.1 kcal mol −1 ) can be found in the case of SO 2 + 2H 2 O + DMA. These lead us to conclude that the SO 2 hydration reaction assisted by MA and DMA is energetically facile. The temporal evolution for hydrated products (CH 3 NH 3 + -HSO 3 - -H 2 O or (CH 3 ) 2 NH 2 + -HSO 3 - -H 2 O) in molecular dynamics simulations indicates that these complexes can self-aggregate into bigger clusters and can absorb water and amine molecules, which means that these hydrated products formed by the hydration reaction may serve as a condensation nucleus to initiate the NPF. [ABSTRACT FROM AUTHOR]
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- 2018
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12. The oxidation mechanism and kinetics of limononic acid by hydroxyl radical in atmospheric aqueous phase.
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Chen, Yanqi, Lv, Guochun, Wang, Yan, Li, Xiaofan, Sun, Juan, Zhou, Xuehua, and Sun, Xiaomin
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OXIDATION kinetics , *HYDROXYL group , *ACTIVATION energy , *ATMOSPHERIC chemistry , *DENSITY functional theory , *OXIDATION - Abstract
Limononic acid (3-isopropenyl-6-oxoheptanoic acid, LA), as an important precursor of secondary organic aerosols (SOA), has attracted extensive attention in the field of atmospheric chemistry. However, its microscopic oxidation mechanism is still unclear. In this study, the density functional theory calculations were conducted to study the oxidation mechanism of LA by ·OH in aqueous phase. The results show that the reactions of hydroxylation are more likely to occur than the dehydrogenation reaction, because of the lower free energy barrier (2.3–5.4 kcal mol−1). At 298 K, the total rate constant of the reaction initiated by ·OH is 1.06 × 1010 M−1 s−1, which fits the experimental value well. Among all reactions, the hydroxylation reaction in C 9 site of LA is the most favorable pathway, and the corresponding hydroxylation intermediate (IM4) can react with ·OH, H 2 O, dissolved O 2 , and HO 2 ·. Three important tropospheric free radicals (R·, RO· and RO 2 ·) are generated during the subsequent reaction process. Meanwhile alcohols, ketones, aldehydes, and oxidized acids can be formed in the overall reaction scheme. These products are the precursor for the formation of SOA, and this transformation process will increase the O/C ratio of aqueous phase SOA. This study has an important significance for understanding the oxidation mechanism of monoterpenoids in the atmospheric aqueous phase. [Display omitted] • OH-addition reaction of C 9 site is more like to occur of LA. • The intermediate can react with ·OH, H 2 O, dissolved O 2 , and HO 2. • Three important tropospheric free radicals (R·, RO· and RO 2 ·) are generated during the reaction process. • The transformation process will increase the O/C ratio of aqueous phase SOA. [ABSTRACT FROM AUTHOR]
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- 2023
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13. Theoretical insight into the degradation of diclofenac by hydroxyl and sulfate radicals in aqueous-phase: Mechanisms, kinetics and eco-toxicity.
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Yang, Jiaoxue, Lv, Guochun, Li, Tingting, Sun, Shuchen, and Sun, Xiaomin
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HYDROXYL group ,DICLOFENAC ,DENSITY functional theory ,POISONS ,ANTI-inflammatory agents ,WATER chlorination - Abstract
Diclofenac (DCF) is a widely used non-steroidal anti-inflammatory drug, which has attracted more and more attention due to its biotoxicity and refractory degradation. The objective of this study was to systematically analysis the transformation mechanisms, kinetics and toxicity of DCF initiated by •OH and SO 4
•– in persulfate oxidation process. In this study, the degradation mechanism of DCF has been performed by density functional theory (DFT) methods, and the toxicity of the by-products was studied by computational toxicology. The results show that the reactivity of benzylic position of DCF is higher than that of chlorinated aromatic ring, indicating •OH and SO 4•– are more likely to react in benzylic position. By comparing the initiation reactions of •OH and SO 4•– , it was found that •OH-initiations were the predominant pathway in the degradation process. The kinetic calculations show that the degradation rate constants were positively correlated with temperature. Furthermore, the calculated toxicological results indicate that the toxicity level of most products is reduced, but the hydrolysates remain toxic and deserve more attention for the degradation by-products of DCF. The comprehensive theoretical study is helpful to reveal the microscopic mechanism of DCF transformation and AOP-wastewater remediation. [Display omitted] • The degradation mechanisms of DCF by •OH and SO 4 •‾ in aquatic environment were studied by theoretical calculation methods. • The rate constants of DCF with •OH and SO 4 •‾ were calculated. • High temperature is more favorable for the initial degradation of DCF. • The eco-toxicity of degradation by-products decreased, but hydrolysates remain toxic. [ABSTRACT FROM AUTHOR]- Published
- 2022
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14. Degradation mechanism and eco-toxicity assessment of bisphenol S based on peroxymonosulfate activated with Co3O4 surfaces.
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Wang, Zehua, Lv, Guochun, Zhang, Chenxi, and Sun, Xiaomin
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BISPHENOL A , *BISPHENOLS , *PEROXYMONOSULFATE , *DENSITY functional theory , *CATALYSTS , *SURFACE energy , *CHARGE transfer , *HYDROQUINONE - Abstract
In this paper, the degradation mechanism and eco-toxicity assessment of bisphenol S (BPS) was studied in the aqueous environment based on the heterogeneous activation of peroxymonosulfate (PMS) through spinel tricobalt tetraoxide (Co 3 O 4) catalyst using density functional theory (DFT) and computational toxicology methods. The result indicates that (100) and (311) surfaces have the higher proportion of bivalent cobalt, the increase of charge transfer, negative adsorption energy, and the lower surface energy. They can more effectively promote the decomposition of PMS to generate reactive oxide species. When generated oxidants react with BPS, HO•-addition reaction at the ortho -C atom-sites plays a dominant role in the system Co 3 O 4 /PMS. The presence of SO 4 •-, HO•, and O 2 promotes the formation of transformation intermediates and products. The formation pathways of important experimental intermediates hydroquinone, p -hydroxybenzenesulfonic acid, and 3, 4-dihydroxybenzenesulfonic acid are identified. And, some hydroxylation products that are not identified in the experiment are determined. The eco-toxicity evaluation shows that most of the decomposition products are completely harmless or significantly reduced compared to BPS. This study not only provides insights into the degradation mechanism of BPS in Co 3 O 4 /PMS system, but also is expected to be a guide for further experimental research and the design and optimization of the activated catalysts in sulfate radical-based advanced oxidation technologies. [Display omitted] • Co 3 O 4 (100) and (311) surfaces are more effectively promote the PMS decomposition. • The most reactive-site of BPS is the ortho -C atom. • OH.•-initiated plays a dominant role in the degradation process of BPS, not SO 4 •-. • Hydroquinone and p-hydroxybenzenesulfonic acid are important intermediates. • Compared with BPS, most decomposition products are harmless or reduced. [ABSTRACT FROM AUTHOR]
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- 2022
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15. Insight into the formation of organosulfur compounds from the reaction of methyl vinyl ketone with sulfite radical in atmospheric aqueous phase.
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Lv, Guochun, Zhang, Heng, and Sun, Xiaomin
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- 2021
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16. New insight into photodegradation mechanisms, kinetics and health effects of p-nitrophenol by ozonation in polluted water.
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Wang, Ning, Lv, Guochun, He, Lin, and Sun, Xiaomin
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OZONIZATION , *THERMODYNAMICS , *COMPUTATIONAL chemistry , *PHOTODEGRADATION , *SMALL molecules , *ORGANIC acids - Abstract
• P-NP is completely degraded by tertiary ozonation. • The k total of degradation of p-NP initiated by O 3 alone is slow. • OH· can greatly promote the tranformation of p-NP in O 3 /UV process. • Some metabolites still have carcinogenic and teratogenic effects on organisms. P -nitrophenol (p-NP) is a recalcitrant organic compound attracted great environmental attention, but its degradation mechanism is indeterminacy, which challenges its treatment, migration, transformation and ecological impact in the environment. In the present study, the aqueous-phase decomposition process of p-NP initiated by O 3 has been investigated by a theoretical calculation method. The detailed possible reaction pathways for the oxidative degradation of p-NP by ozone have been proposed. The chemical reaction thermodynamics results show that the reaction barriers of all ozone-initiated pathways are below 15 kcal·mol−1, indicating that ozone can completely initiate the oxidation of p-NP under natural conditions. However, the kinetic results show that the initiation reaction of p-NP by ozone alone is relatively slow compared to the reaction by OH. Interestingly, under ultraviolet (UV) radiation, the dissolved ozone interacts with water and produces two active radicals: OH and HO 2 . The reaction rate of p-NP initiated with OH is much higher than that with ozone, implying that the OH produced in the photochemical process can improve the removal efficiency of p-NP. The intermediates generated in the ozone-initiated reaction have been found to decompose into small molecule organic acids, aldehydes and ketones. The potential carcinogenicities and teratogenicities of the transformation products have also been studied, and some of them still have carcinogenic activity, which deserve further attention. In addition, to our knowledge, this may be the first computational chemistry study on the degradation of p-NP initiated by HO 2 . All the results provide a new fundamental understanding for the migration and transformation of p-NP in water environment, and indicate that further assessment is needed for the impact of p-NP and especially its transformation products on the ecological environment in a significant way. [ABSTRACT FROM AUTHOR]
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- 2021
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17. Catalytic oxidation mechanism of NO to HNO3 on TiO2 (101) and (001) surfaces and the influence factors on NO removal: A DFT study.
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Wang, Zehua, Lv, Guochun, Zhang, Chenxi, and Sun, Xiaomin
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CATALYTIC oxidation ,TITANIUM dioxide ,ACTIVATION energy ,DENSITY functionals ,SELECTIVE catalytic oxidation - Abstract
• A DFT study is employed to calculate the catalytic oxidation of NO in this paper. • The removal of NO to HNO 3 is easier to occur on the TiO 2 (001) than (101). • The additional NO molecule can improve the formation of HONO not HNO 3. • Additional NO effectively reduce the barrier energy in oxidation of NO and O 2. • Trans-ONONO 2 preferentially generates than NO 2 in the presence of additional NO. Theoretical study on the selective catalytic oxidation of NO to form HNO 3 on the different TiO 2 (001) and (101) surfaces was performed by DFT calculations. The addition of additional NO molecules to the oxidation process also is discussed. The result shows that HNO 3 is more easy to generate on (001) than (101) surface. The adsorbed H atom on surface is beneficial for the transformation of O 2 to the superoxide radical (O 2
·− ) that has a favorable role for the oxidation of NO on surface. In addition, it is manifestly demonstrated that the participation of the additional NO in the reaction of NO and O 2 not only modifies the known NO oxidation pathway (N O → N O 2 → H N O 3), but also affects the existence of the product HNO 3. The trans-ONONO 2 can firstly be formed if the additional NO molecule involves in the oxidation reaction in the beginning. When the additional NO molecule encounter with the precursor (H···NO 3) of oxidation product (HNO 3), it can improve the formation of HONO not HNO 3. This study gains more insight into the mechanism of NO oxidation and has a potential atmospheric importance. [ABSTRACT FROM AUTHOR]- Published
- 2021
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18. The role of air-water interface in the SO3 hydration reaction.
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Lv, Guochun and Sun, Xiaomin
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AIR-water interfaces , *GAS phase reactions , *HYDRATION , *MOLECULAR dynamics , *INTERFACIAL reactions , *ION pairs , *POZZOLANIC reaction - Abstract
H 2 SO 4 is an important pollutant in the atmosphere, and it mainly be formed through the oxidation of SO 2. SO 3 produced from the oxidation of SO 2 is a precursor of H 2 SO 4. Considering that understanding of SO 3 hydration reaction at the air-water interface is limited, we combined the classical molecular dynamics simulations (classical MD) with Born–Oppenheimer MD simulations and ab initio calculations to study the SO 3 reaction with H 2 O at air-water interface. The free energy and impinging results indicate that the SO 3 molecules can easily be trapped by water droplets. After uptake by the interface, the SO 3 can react rapidly with water molecules to form the ion pair of HSO 4 − and H 3 O+ or H 2 SO 4 within a few picoseconds. In the interfacial hydration mechanism, the loop-structure formation is not prerequisite of the hydration reaction, which is obviously different from the corresponding gas-phase hydration reaction of SO 3. The work is meaningful for understanding the heterogeneous formation of H 2 SO 4 and the contribution of interfacial reaction to the new particle formation. • SO 3 can easily be trapped by water droplets. • The SO 3 hydration mechanism at the air-water interface was considered. • The loop-structure formation is not prerequisite of interfacial hydration of SO 3. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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19. The oxidation mechanism of 3,4-dihydroxy-2-butanone in the aqueous phase for secondary organic aerosols formation.
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Xu, Luyao, Lv, Guochun, Liu, Wen, Sun, Xiaomin, Zhang, Chenxi, and Li, Zhiqiang
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AEROSOLS , *OXIDATION , *ACETIC acid , *OZONIZATION , *OZONE , *PYRUVALDEHYDE - Abstract
3,4-dihydroxy-2-butanone (DHBO) is a major oxidation product of IEPOX and can easily be oxidized in tropospheric aqueous phase. The aqueous oxidation mechanism of DHBO has investigated by DFT and initial reaction rate constants also have calculated through TST. In the aqueous phase, the following trend in reactivity of initial reaction can be obtained: OH ≫ SO 4 − > NO 3 , which bases on the calculated rate constants (k (OH) = 1.20 × 108 L mol−1 s−1, k (SO 4 −) = 8.51 × 105 L mol−1 s−1 and k(NO 3) = 2.86 × 105 L mol−1 s−1) at 298 K and 1 atm. After initial reaction, the major products of DHBO further react with OH radical at presence of O 2. The final products include acetic acid and methylglyoxal, which are important SOA precursors. This work provides a reference for oxidation mechanism of dihydroxycarbonyl of isoprene-driven in aqueous and help understand SOA formation. Image 1 • The aqueous oxidation mechanism of DHBO has been studied. • The OH.•-initiated reaction rate constant is 1.20 × 108 L mol−1 s−1 at 298 K and 1 atm. • Acetic acid and methylglyoxal of main products contribute to aqSOA formation. • The HO 2 and RO 2 of minor products increase the ozone yield. [ABSTRACT FROM AUTHOR]
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- 2020
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20. Distribution, transformation and toxicity evaluation of 2,6-Di-tert-butyl-hydroxytotulene in aquatic environment.
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Wang, Yan, He, Lin, Lv, Guochun, Liu, Wen, Liu, Jiashuo, Ma, Xiaohui, and Sun, Xiaomin
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DENSITY functional theory ,FOOD chains ,METHYL groups ,ECOLOGY ,INDUSTRIAL design - Abstract
2,6-Di-tert-butyl-hydroxytotulene (BHT), as a significant synthetic phenolic antioxidant (SPA), has received increasing attention in the environmental field. In the present study, the BHT is confirmed to be mainly distributed in the liquid phase in the environment base on the Aspen PLUS simulation results. The mechanism and kinetics of BHT transformation initiated by OH radicals were conducted in aquatic environment using density functional theory (DFT) method. Briefly, seven initiation reactions and three detailed transformation pathways of BHT were reported. The H atoms in the t-butyl and methyl group were found more favorable to be abstracted. The C1 site of the BHT was susceptible to addition by OH radicals. Rate constants of different initial reactions were calculated and they were inhibited by temperature rise. Meanwhile, the acute and chronic toxicities of BHT and its metabolites were evaluated at three different trophic levels using the ECOSAR program. During the degradation process, the toxicities of these metabolites gradually decreased, but the toxicities of the final product 2,6-di-tert-butyl-2,5-cyclohexadien-1,4-dione (BHT-Q) were significantly increased. These results could help to reveal the transformation mechanism and risk assessment of BHT in aquatic environment, and further design the experimental and industrial applications of SPAs. Image 1 • Aspen PLUS simulation was used to clarify that more than 90% of the BHT in the environment exist in liquid phase. • This study demonstrated that BHT was more easily oxidized on p-methyl group to generate metabolites. • The product BHT-Q has strong toxicity to aquatic ecosystem. BHT is easily oxidized by OH radicals in aquatic environment to form BHT-CHO, BHT-Q and other metabolites that are more harmful to the aquatic environment. [ABSTRACT FROM AUTHOR]
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- 2019
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21. Optimization of the adsorption performance of herbal residues as lanthanide ion-modified carriers for phosphate by fly ash and its application.
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Zhou, Caigao, Chen, Zihan, Lv, Guochun, Xu, Changlian, Wang, Guiyin, Zhang, Shirong, Yang, Zhanbiao, Cheng, Zhang, Cai, Junzhuo, Li, Ting, Pu, Yulin, Pu, Zhien, Qi, Xin, Xiao, Guangli, and Xu, Xiaoxun
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PHOSPHATE removal (Water purification) , *FLY ash , *WASTE treatment , *CALCIUM ions , *COAL ash , *RARE earth metals , *ADSORPTION (Chemistry) , *ADSORPTION capacity - Abstract
In order to mitigate the harmful effects of eutrophication in water bodies, the applications of lanthanum-modified materials for phosphate removal from wastewater have attracted much attention. Unlike conventional adsorbents, plant wastes usually have poor adsorption abilities and are difficult to be reused for desorption of phosphate due to their small pore sizes and ununiform loading of modified ions. In this paper, a composite adsorbent (LC-MM) was synthesized by hydrothermal treatment of waste traditional Chinese medical materials (MMs) with load of lanthanum carbonate and co-heating treatment with coal fly ash (CFA), which was applied to remove phosphate from water. The results showed that maximum adsorption capacity of LC-MM was 52 mg g−1, and the LC-MM showed appreciable adsorption capacity of phosphate for agricultural wastewater in the presence of complex interfering ions and for urban surface waters with low phosphate concentrations. Five adsorption-desorption cycles showed good reusability. The mechanism study showed that the La3+ ions were more uniformly distributed on the surface of the absorbents with the introduction of Fe3+, Al3+, Mg2+ and Ca2+ ions in CFA. The ligand exchange between phosphate and carbonate, the internal spherical complexation formed by lanthanum ion and phosphate, and surface chemical precipitation attachment are the main reasons why the adsorption capacity of LC-MM approached or even surpassed that of conventional lanthanum-modified adsorbents. In conclusions, this work proposed an effective method for the modification of plant materials. [Display omitted] • Reuse of two types of waste after treatment. • A method to improve the inefficiency of phosphate adsorption by plant materials. • The mechanism of modification is to influence the state of lanthanum on the surface of the carrier. • Effect of phosphate separated after adsorption on plant growth. [ABSTRACT FROM AUTHOR]
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- 2024
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22. Theoretical insight into the aqueous transformation mechanism of terbutaline using O3 and •OH of advanced oxidation processes.
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Yang, Jiaoxue, Xu, Youxin, Lv, Guochun, Li, Tingting, and Sun, Xiaomin
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TERBUTALINE , *ACTIVATION energy , *ELECTRONIC structure , *DENSITY functional theory , *STRUCTURE-activity relationships - Abstract
Terbutaline (TBL, an β-agonists pharmaceuticals) is one of the pharmaceuticals and personal care products (PPCPs), which has caused many environmental concerns due to its eco-toxicological effects in aquatic environment. In this research, density functional theory (DFT) and quantitative structure–activity relationships (QSARs) toxicity methods were performed to systematically elucidate the transformation mechanisms and ecological risk of TBL degraded by •OH and O 3. By analyzing the structure and electronic properties of TBL, the •OH-addition, H-abstraction, single electron transfer and 1, 3-cycloaddition ozonation degradation pathways were mainly investigated. The lowest energy barriers of •OH and O 3 initiated reactions in the degradation process were 7.33 and 18.49 kcal mol−1 respectively, which indicated that the •OH degradation process was more likely to occur than O 3 induced reactions from a thermodynamic perspective. The kinetic rate constants of O 3 and •OH at 298 K were calculated as 7.58 M−1 s−1 and 1.02 × 109 M−1 s−1, respectively. Furthermore, the subsequent intermediates could further transform into hydroxylation substitutes, glyoxylic acid and ketoaldehyde by-products. Based on toxicity assessments, parent reactant TBL can exhibit harmful acute and chronic toxicity to daphnid (identified by LC 50 33.2 mg L−1 and ChV 2.34 mg L−1). The toxicity of most of the degradation products was reduced to harmless level compared with the parent reactant TBL. This work provided a molecular level understanding for evaluating the contribution of O 3 and •OH to the removal of TBL from wastewater by theoretical calculations. [Display omitted] • The degradation mechanisms of terbutaline by.•OH and O 3 in aquatic environment were studied by theoretical calculation methods. • The main degradation mechanism was proposed as an.•OH-addition reaction on the C1 site of aromatic ring of terbutaline. • The calculated total rate constants of.•OH and O 3 -initiated reaction were 1.02 × 109 M−1 s−1 and 7.58 M−1 s−1 during the degradation of terbutaline at 298K. • The eco-toxicity of degradation by-products were changed compared by terbutaline. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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23. Experimental and theoretical insight into the transformation behaviors and risk assessment of Flutamide in UV/O3/PMS system.
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Li, Xiaofan, Wang, Ning, Lv, Guochun, Zhang, Yonglei, Chen, Yanqi, Liu, Xiaoyu, Sun, Xiaomin, and Zhu, Fanping
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BEHAVIORAL assessment , *FLUTAMIDE , *AT-risk behavior , *RISK assessment , *CHEMICAL decomposition - Abstract
Nowadays, the widespread existence and potential adverse effects of emerging micropollutants in waters have prompted the search for effective treatment methods. In this study, the feasibility of UV/O 3 /PMS (peroxymonosulfate, HSO 5 −) method for the elimination of Flutamide (FLU) was comprehensively investigated, with focus on transformation behaviors and risk assessment. The results showed that the UV/O 3 /PMS method has excellent oxidation capability to FLU with the elimination efficiency of 83.7% within 40 min. In addition, the radical (·OH and SO 4 −·) oxidation occupies greater advantages in the initiation reaction pathways of FLU compared to non-radical (O 3 and 1O 2) oxidation. With the participation of H 2 O 2 , H 2 O, O 2 , and ·OH, eleven transformation products (TPs) are generated through hydroxylation, demethylation, and decomposition reactions. According to the risk assessment results, the toxicity of most TPs gradually decreased, but the residual developmental toxicity could not be ignored. Further, the environmental persistence of FLU was evaluated with respect to natural water and advanced oxidation processes. These findings could help to advance the fundamental understanding of emerging micropollutants in the aquatic environments, and provide a basis for their practical application in water treatment. [Display omitted] • The transformation mechanisms involved in UV/O 3 /PMS system were elucidated. • ·OH and SO 4 −· are the major contributors to FLU degradation compared to O 3 and 1O 2. • FLU degradation was caused by hydroxylation, demethylation, and decomposition paths. • UV/O 3 /PMS is a promising treatment method for O 3 or UV-refractory micropollutants. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
24. Co-hydrothermal carbonization of rape straw and industrial sewage sludge – Applications of hydrochar for N and P adsorptions and for agricultural/horticultural purposes.
- Author
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Xu, Chang-Lian, Li, Ailian, Xu, Xiaoxun, Yang, Zhanbiao, Wang, Guiyin, Cheng, Zhang, Zhang, Shirong, Li, Ting, Pu, Yulin, Lv, Guochun, Cai, Junzhuo, Zhou, Wei, Pu, Zhien, and Qi, Xin
- Subjects
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SEWAGE sludge , *AGRICULTURE , *INDUSTRIAL wastes , *AGRICULTURAL wastes , *CARBONIZATION , *ADSORPTION (Chemistry) - Abstract
Reuse of agricultural and industrial wastes simultaneously to prepare hydrochars (HCs) for removal of NH 4 + and PO 4 3− in practical sewage without additional wastes produced is still a challenge. Herein, HCs were fabricated by combination of rape straw and industrial sewage sludge to remove NH 4 + and PO 4 3− from hoggery effluent. Synthesis conditions were firstly optimized and optimized HC (OPT-HC) was further applied to adsorb NH 4 + and PO 4 3−. Monolayer and Pseudo-first-order as well as Pseudo-second-orders were confirmed via adsorption kinetic and isothermal adsorption studies. Morphologies and surface areas of the OPT-HC did not show any transformations before and after adsorption of NH 4 + and PO 4 3−. The OPT-HC after adsorption of NH 4 + and PO 4 3− (OPT–HC–N/P) was further applied as fertilizer for planting Ping-pong Chrysanthemum. Results indicate that the OPT–HC–N/P can improve comprehensive qualities of the Ping-pong Chrysanthemum such as plant height, fresh, Vitamin C, Chlorophyll, soluble protein and sugar because the OPT–HC–N/P can provide extra N and P elements and also promote to release available K in soil. OPT–HC–N/P treated Ping-pong Chrysanthemum open flowers in advance. Thus, two kinds of wastes were re-utilized to remove N and P in real-life effluent. • Agricultural and industrial wastes were used to prepare hydrochars. • The hydrochars can be applied to remove N and P in hoggery effluent. • No wastes produced after removal of N and P. • Horticultural/agricultural applications were further realized. • Qualities of Ping-pong Chrysanthemum improved by HC after adsorption of N and P. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
25. Enhanced simultaneous removal of phosphate and ammonium from swine wastewater using magnetic magnesium–loaded Chinese herbal medicine residues: Performance, mechanism, and resource utilization.
- Author
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Wang, Guiyin, Liu, Ruoqi, Yang, Zhanbiao, Liu, Wei, Xu, Xiaoxun, Zhang, Shirong, Cheng, Zhang, Lv, Guochun, Xu, Changlian, Cai, Junzhuo, and Pu, Zhien
- Subjects
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PHOSPHATE removal (Sewage purification) , *AMMONIUM phosphates , *HERBAL medicine , *CHINESE medicine , *AMMONIUM , *SEWAGE , *SWINE - Abstract
[Display omitted] • Novel MM–TCMRs were synthesized for concurrent removal of phosphate and ammonium. • MM–TCMRs exhibits excellent phosphate and ammonium adsorption capacity. • Potential phosphate and ammonium removal mechanism with MM–TCMRs was proposed. • >70 % phosphate and ammonium were recovered from swine wastewater after four cycles. • Nutrient–loaded MM–TCMRs is applied as a fertilizer to promote alfalfa growth. Magnetic magnesium (Mg)–loaded Chinese herbal medicine residues (MM–TCMRs) were fabricated to simultaneously remove and recover phosphate and ammonium from wastewater. The MM–TCMRs exhibited larger specific surfaces and rougher structures with massive spherical particles than those of original residues. They could be separated by adjusting the magnetic field. The phosphate and ammonium adsorption by MM–TCMRs were matched with the pseudo–second–order model, while the Langmuir model yielded the maximum adsorption capacities of 635.35 and 615.57 mg g−1, respectively. Struvite precipitation on the MM–TCMRs surface was the primary removal mechanism with electrostatic attraction, ligand exchange, intra–particle diffusion, and ion exchange also involved. The recyclability of MM–TCMRs confirmed their good structural stability. More importantly, the nutrient–loaded MM–TCMRs enhanced alfalfa growth and improved soil fertility in planting experiments. Collectively, the MM–TCMRs are promising candidates for nutrient removal and recovery from wastewater. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
26. Theoretical insight into the oxidation mechanism of NO2 and SO2 on TiO2 surface: The role of H2O, NH3 and SO42-.
- Author
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Wang, Zehua, Zhang, Chenxi, Lv, Guochun, and Sun, Xiaomin
- Subjects
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ACTIVATION energy , *OXIDATION , *WATER , *TITANIUM dioxide , *SULFUR dioxide , *ATMOSPHERIC ammonia - Abstract
In this paper, density-functional theory (DFT) was employed to investigate the reaction mechanism of SO 2 and NO 2 and the important role of intermediate N 2 O 4 formation. In addition, the effect of pure particulate surface (TiO 2) and particulate surface containing other atmospheric components (H 2 O, NH 3 and SO 4 2−) on the conversion of SO 2 and NO 2 to sulfate also was analyzed. The detailed information that intermediate N 2 O 4 acts as the oxidant was demonstrated in this oxidation reaction of SO 2 and NO 2 (as a rate-determining step). The pure particulate surface (TiO 2) has hardly effect on the oxidation process of SO 2 and N 2 O 4. Whereas, different amounts of H 2 O and NH 3 molecules as well as SO 4 2−, contained on the particulate surface, can effectively reduce the activation energy of oxidation step. And, the optimal process is that SO 2 is oxidized by cis-ONONO 2 with the energy barrier of 4.54 kcal/mol when one NH 3 molecule and one H 2 O molecule are contained on the TiO 2 (101) surface. When more H 2 O molecules are contained on particulate surface, SO 2 tends to form HSO 3 − first. However, HSO 3 − is more difficult to be further oxidized by asy-ONONO 2 than SO 2. This study gains more insight into the contribution of SO 2 and NO 2 to haze and the potential impact of atmospheric constituents (including H 2 O/NH 3 /TiO 2 and SO 4 2−/TiO 2) on the formation sulfate. Image 1 • Asy-ONONO 2 acted as oxidant is easily contained on the particulate surface. • The oxidation of SO 2 and asy-ONONO 2 is easy than HSO 3 −. • The oxidation step of SO 2 and N 2 O 4 is the rate-determining step. • Pure particulate surface has hardly effect on the rate-determining step. • Particulate containing H 2 O, NH 3 and SO 4 2− promote the reaction of SO 2 and N 2 O 4. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
27. Experimental and theoretical insights into the RCS-Involved electro-catalytic transformation of 4-nitrophenol.
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Wang, Yan, He, Lin, Lv, Guochun, and Sun, Xiaomin
- Subjects
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AMINO group , *WATER disinfection , *WATER chlorination , *GROUP 15 elements , *DENSITY functional theory , *ARSENIC removal (Water purification) , *GROUP formation , *NITROPHENOLS - Abstract
The important role of reactive chlorine species (RCS) in electrochemical system has been widely concerned for water disinfection recently. In this study, we built an electrochemical system using carbon nanotube as cathode and oxide precursor (Ti/SnO 2 –Sb 2 O 5 –IrO 2) as anode, where RCS was produced from Cl−. This system was used to degrade nitrogen contaminants, i.e. NO 3 − and 4-nitrophenol. Optimization of the reaction conditions was carried out by a treatment of inorganic nitrogen contaminant NO 3 − and the optimal condition of the electrochemical system was determined at U = 5.5 V, and pH = 10 with a Cl− concentration of 2000 mg L−1, and the removal efficiency of NO 3 − can reach up to 60.6% in 150 min. Under the optimal condition, a common nitrogenous organic pollutant, 4-nitrophenol was treated and a removal efficiency of nearly 100% in 90 min. To investigate the detailed degradation mechanism in the applied electrochemical system, a combined method of products identification and density functional theory (DFT) calculation was employed. It concluded that Cl radicals' generation was stimulated was stimulated by the OH radicals after adding Cl− into the electrochemical system. These two radicals jointly promoted the transformation of 4-nitrophenol resulting in the formation of more toxic organic and inorganic substances. In addition, a conversion of organic nitro group to amino group leading to the formation of 4-aminophenol was found and explained by the indirect reduction theory. Image 1 • 4-Nitrophenol can be converted into NO 3 −, NO 2 −, NH 4 + and other inorganic nitrogen. • Adding chloride ions inhibits the formation of NH 4 + transformed from 4-nitrophenol. • The mechanism of converting a nitro group into an amino group is elucidated. • The toxicity of chlorine-containing transformation products of 4-nitrophenol is enhanced. [ABSTRACT FROM AUTHOR]
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- 2021
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28. Characterization of ionic liquids removing heavy metals from electroplating sludge: Influencing factors, optimisation strategies and reaction mechanisms.
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Cao, Chenchen, Xu, Xiaoxun, Wang, Guiyin, Yang, Zhanbiao, Cheng, Zhang, Zhang, Shirong, Li, Ting, Pu, Yulin, Lv, Guochun, Xu, Changlian, Cai, Junzhuo, Zhou, Wei, Li, Feng, Pu, Zhien, and Li, Xiaofan
- Subjects
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IONIC liquids , *ELECTROPLATING , *COPPER , *LIQUID metals , *REGRESSION analysis , *HEAVY metals - Abstract
The disposal of electroplating sludge (ES) is a common concern of researchers. Currently, it is difficult to achieve effective fixation of heavy metals (HMs) using traditional ES treatment. As green and effective HMs removal agents, ionic liquids can be used for the disposal of ES. In this study, 1-butyl-3-methyl-imidazole hydrogen sulphate ([Bmim]HSO 4) and 1-propyl sulphonic acid-3-methyl imidazole hydrogen sulphate ([PrSO 3 Hmim]HSO 4) were used as washing solvents for the removal of Cr, Ni, and Cu from ES. In reaction with increased agent concentration, solid–liquid ratio, and duration, the amount of HMs eliminated from ES rises, whereas opposite patterns were shown in response to rising pH. The quadratic orthogonal regression optimisation analysis also revealed that the ideal washing specifications for [Bmim]HSO 4 were 60 g L−1, 1:40, and 60 min, respectively, for agent concentration, solid–liquid ratio, and washing time, while those for [PrSO 3 Hmim]HSO 4 were 60 g L−1, 1:35, and 60 min, respectively. Under the optimal experimental conditions, the Cr, Ni, and Cu removal efficiencies for [Bmim]HSO 4 were 84.3, 78.6, and 89.7%, respectively, and those values for [PrSO 3 Hmim]HSO 4 were 99.8, 90.1, and 91.3%, respectively. This was mainly attributed to that ionic liquids enhance metal desorption through acid solubilisation, chelation, and electrostatic attraction. Overall, ionic liquids are reliable washing reagents for ES contaminated by HMs. [Display omitted] • Ionic liquids exhibited efficient Cr, Ni and Cu removal from electroplating sludge. • Effect of various experimental conditions on heavy metals removal was explored. • Removal mechanism of ionic liquids to heavy metals was described. • The finding will provide new ideas for the disposal of electroplating sludge. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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29. Application and mechanism analysis of functionalized ionic liquids in copper regeneration from electroplating sludge.
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Li, Feng, Xu, Xiaoxun, Cao, Chenchen, Yang, Zhanbiao, Wang, Guiyin, Li, Ting, Pu, Yulin, Zhang, Shirong, Cheng, Zhang, Lv, Guochun, Xu, Changlian, Xian, Junren, Yang, Yuanxiang, and Pu, Zhien
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COPPER , *CHEMICAL processes , *IONIC liquids , *ELECTROPLATING , *CHEMICAL reactions , *WATER treatment plant residuals - Abstract
Hydrometallurgy is the main method to regenerate valuable metals from electroplating sludge and reduce its environmental hazards. As a key step to efficiently recover metals, it is important to choose an environmentally friendly and efficient leaching agent. In this work, four green ionic liquid (ILs) ([BMIm]HSO 4 , [HOOCMIm]HSO 4 , [BSO 3 HMIm]HSO 4 , and [BSO 3 ]Py.HSO 4) were used to leach copper from copper–rich electroplating sludge (C–ES). The tested ILs could effectively leach copper from C–ES, but functionalized ILs have better leaching efficiency, especially sulfonate ILs, which could remove 100% of Cu from C–ES under optimal conditions. Kinetics studies showed that the leaching process of controlled by chemical reaction and material diffusion, and the apparent activation energies were 39.21, 0.98, 14.47, and 41.93 kJ mol−1, respectively. Introducing functional groups (such as carboxyl and sulfonate group) which can complex with metals on cations can enhance the H+ release and complexation ability of ILs, improve the mass transfer efficiency between liquid–solid phase, and thus improve the copper leaching ability by ILs. These findings are of great significance for selecting functional ILs to efficiently regenerate copper and the resource utilization from C–ES. [Display omitted] • An efficient leaching method of copper from electroplating sludge is proposed. • The leaching behavior and the leaching mechanism of copper in ILs was analysed. • Functionalized ILs had better hydrogen release and metal complexation ability. • Sulfonate functionalized ILs is most conducive to copper recovery from C-ES. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
30. La(III) loaded Fe(III) cross–linked chitosan composites for efficient removal of phosphate from wastewater: Performance and mechanisms.
- Author
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Wang, Guiyin, Yue, Xiangzhi, Zhang, Shirong, Geng, Qing, Zheng, Jingjie, Xu, Xiaoxun, Li, Ting, Pu, Yulin, Li, Yun, Jia, Yongxia, Lv, Guochun, Xu, Changlian, Wu, Ganxue, Yang, Zhanbiao, and Cheng, Zhang
- Subjects
- *
PHOSPHATE removal (Sewage purification) , *SEWAGE , *EUTROPHICATION control , *CHITOSAN , *SOIL amendments , *ADSORPTION capacity , *PHOSPHATES , *PHOSPHATE fertilizers - Abstract
The cost–effective removal and recovery of phosphate from wastewater is of great importance to controlling eutrophication and alleviating the phosphorus resource exhaustion crisis. Herein, chitosan (Cs) encapsulated bimetallic lanthanum (La) and iron (Fe) metal(hydro) oxides (La/Fe–Cs) composites were fabricated using a co–precipitated method for enhanced phosphate removal and recovery. The La/Fe–Cs composites had rough and raised spongy–like surfaces coated with La/Fe (hydr)oxide particles with a high specific surface area of 109.84 m2 g−1, providing more potential binding sites for phosphate capture. The La/Fe–Cs composites with a 1:2 La–to–Fe molar ratio exhibited a maximum adsorption capacity of 67.52 mg g−1 for phosphate at 308 K, calculated using the Langmuir model, which was 211% higher than that of monometallic Fe–Cs composites. Meanwhile, this composite also showed a high phosphate removal rate (63–95%) in an extensive applicable pH range (3.00–10.00) and rapid adsorption within 10 min (up to 94%). Moreover, the adsorption of phosphate by La/Fe–Cs composites was mildly disturbed against co–existing ions of NO 3 −, Cl−, and humic acid, while adsorption capacities were reduced by almost 13–45% with the existence of SO 4 2−, HCO 3 −, and CO 3 2−. The FTIR, XPS, and DFT results suggested that La–doped facilitated phosphate removal and the predominant mechanisms involved electrostatic interaction, surface precipitation, and inner–sphere complexation processes. Additionally, La/Fe–Cs composites also illustrated excellent efficiencies in simultaneous scavenging phosphate and ammonia from eutrophication and poultry wastewater. These results highlight bimetallic La/Fe–Cs composites are promising candidates for efficient elimination and recovery of phosphate from real wastewater, and subsequently could be used as slow–release fertilizers or soil amendments. [Display omitted] •Bimetallic La/Fe–Cs composites were synthesized for phosphate removal. • The derived bimetallic La/Fe–Cs composites showed excellent phosphate adsorption capacity of 67.52 mg g−1 • Mechanisms driving phosphates adsorbed onto the La/Fe–Cs composites were elucidated by FTIR, XPS, and DFT. • High efficiency in scavenging phosphate from eutrophication wastewater and poultry wastewater. • The phosphate–loden La/Fe–Cs composites can be used as slow–release fertilizers or soil amendments. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
31. Determination of reactions between Criegee intermediates and methanesulfonic acid at the air-water interface.
- Author
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Ma, Xiaohui, Zhao, Xianwei, Huang, Zixiao, Wang, Junjie, Lv, Guochun, Xu, Fei, Zhang, Qingzhu, and Wang, Wenxing
- Abstract
In recent years, Criegee chemistry has become an important research focus due to its relevance in regulating concentrations of tropospheric OH radicals, hydroperoxides, sulfates, nitrates, and aerosols. However, to date, its interface behavior remains poorly understood. Thus, in this study, we used the Born-Oppenheimer molecular dynamics (BOMD) simulation method to explore the reaction mechanisms between Criegee intermediates (CIs) and methylsulfonic acid (MSA) at the air-water interface, then compared the observed behaviors with those in the gas phase. The addition of Criegee intermediates to MSA is nearly a barrierless reaction and follows a loop-structure mechanism in the gas phase. The high rate constants indicate that the Criegee intermediates and MSA reactions are the main acid removal channels. At the water's surface, the interaction of Criegee intermediates with MSA includes three main channels: 1) direct addition reaction, 2) H 2 O-mediated hydroperoxide formation, and 3) MSA-mediated Criegee hydration. These reaction channels follow a loop-structure or a stepwise mechanism and proceed at the picosecond time-scale. The results of this work broaden our understanding of Criegee atmospheric behaviors in polluted urban and marine areas, which in turn will aid in developing more effective pollution control measures. Unlabelled Image • The ab initio dynamics simulation was adopted to simulate the reactions at the air-water interface. • The reaction of MSA with CH 3 CHOO plays an active role in the MSA removal channel. • At the water's surface, the reaction channels follow a loop-structure or a stepwise mechanism. • MSA also acts as a trigger to promote Criegee hydration at the air-water interface. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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