JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2018
·
IF 2.196
Xianze Meng,Xiaozhen Wu,Junsheng Yuan
Solid–liquid equilibria of the quaternary system (Ca2+, Mg2+//SO32–, SO42–-H2O) and its ternary systems (Ca2+//SO32–, SO42–-H2O; Mg2+//SO32–, SO42–-H2O and Ca2+, Mg2+//SO32–-H2O) at 298.15 K were investigated via isothermal solution saturation method. Furthermore, the phase diagrams of these systems were constructed. The results show that the quaternary diagram contains three invariant points, seven univariant curves, and five crystallization fields corresponding to MgSO4·7H2O, MgSO3·6H2O, CaSO3·0.5H2O, Ca(SO3)0.89(SO4)0.11·0.5H2O, and CaSO4·2H2O. The crystallization field of Ca(SO3)0.89(SO4)0.11·0.5H2O is the largest compared with the others. In addition, crystal complex Ca(SO3)0.89(SO4)0.11·0.5H2O also appears in the ternary system (Ca2+//SO32–, SO42–-H2O), which contains two invariant points, three invariant curves, and three crystallization fields. Both of the other two ternary diagrams contain one invariant point, two invariant curves, and two crystallization fields. The Pitzer model was applied to calculate salt solubilities, and the results agree well with the experimental data. Binary and ternary ionic interaction parameters (θSO4,SO3, ψMg,SO4,SO3, ψCa,SO4,SO3, and ψCa,Mg,SO3) and ion pair parameters (CaSO3 and MgSO3) are presented in this work based on the solubilities of these ternary systems.
研究领域:
化学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Zhenjun Xiao,Junlong Zhang,Yijie Lin,Kaixuan Zheng,Zili Lin,Mengyang Niu,Wanlin Lin,Yuchun Hong,Zhongyang Li,Ping Chen,Qingbin Song,Wenying Lv,Guoguang Liu
Developing new technologies to address emerging contaminants are urgently needed. To this end, a novel advanced oxidation system (US/CaSO 3 /PDS) utilizing ultrasound to activate persulfate (PDS) and calcium sulfite (CaSO 3 ) for the effective degradation of emerging contaminants was constructed in this study. The pseudo first-order kinetics constant of Phoxim (PHO) can reach 4.3 × 10 −2 min −1 in US/CaSO 3 /PDS system, revealing the prospects for the treatment of pollutants in water. Electron paramagnetic resonance spectra demonstrated that persulfate anion radicals, hydroperoxyl radicals, hydroxyl radicals, and singlet oxygen were produced in the system. Further, quenching experiments and reactive species probes were used to verify the chemical reaction mechanism of this novel system, and the experimental results highlight the key role of 1 O 2 in the degradation of pollutants thanks to the participation of oxygen. In addition, 11 main products in the PHO degradation process were identified by liquid chromatography-high-resolution precise mass spectrometry, and the possible degradation path of PHO in US/CaSO 3 /PDS system was proposed. US/CaSO 3 /PDS system had high pollutant removal efficiency against a variety of emerging pollutants and was applicable in real water matrix. This study provides a new scheme for the development of advanced oxidation technology based on PDS activation for the removal of refractory emerging pollutants in water.
研究领域:
环境科学
·
化学工程
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产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2024
·
IF 5.2
Jiabao Sun,Chuanrun Li,Zhigang Lei,Yanyan Guo
In this work, the Fe 3 O 4 @ZIF-8 catalyst was prepared by combining Fe 3 O 4 with ZIF-8 for degrading carbamazepine (CBZ) in water, using activated persulfate (PS) and peroxymonosulfate (PMS). We investigated the optimal catalysts and reaction conditions for using PS or PMS as activators by varying the pH, temperature, catalyst dosage, as well as the dosage of PS and PMS, respectively. The results demonstrated that the CBZ removal rate using Fe 3 O 4 @ZIF-8 reached 98.1 % after 30 min with a mass ratio of Fe 3 O 4 to ZIF-8 = 3:1, temperature = 40°C, catalyst dosage = 0.50 g·L −1 , and PS dosage = 0.25 g·L −1 , using pH = 3.0. Characterization results show due to the fact that the presence of ZIF-8 facilitates the dispersion of the catalytic active species Fe 3 O 4 , prevents the agglomeration of the active species, increases the number of active species, and improves the catalytic performance. Furthermore, radical quenching assay and electron paramagnetic resonance spectra successfully identified the main oxidizing components generated in the system, namely SO 4 • − and •OH.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Xin Liu,Baoling Yuan,Jing Zou,Lingbin Wu,Lin Dai,Hongfang Ma,Kai Li,Jun Ma
The activation of persulfate by Fe(II) coupled with hydroxylamine (the HA/Fe(II)/PS system) was highly effective for the degradation of refractory organic contaminants under acidic pH conditions. However, owing to the precipitation of ferric hydroxide and/or the slow reduction from Fe(III) to Fe(II), the HA/Fe(II)/PS system was invalid under neutral and alkaline pH conditions. In this study, it was observed that the degradation of acid orange 7 (AO7) was strongly enhanced over the wide pH range of 2–9 when trace Cu(II) (0.5–5 μM) was spiked into the HA/Fe(II)/PS system. It was evident that Cu(I) was generated via the reduction of Cu(II) by HA in the bimetallic system at both pH 3 and pH 8, and the steady concentration of Fe(II) in the bimetallic system was much higher than that in the HA/Fe(II)/PS system due to the rapid reaction between Fe(III) and Cu(I). Quenching experiments using tert-butyl alcohol, methanol and sodium bromide as the scavengers and electron spin resonance experiments confirmed that the primary reactive species responsible for AO7 degradation were sulfate radical at both pH 3 and pH 8, rather than hydroxyl radical and Cu(III). Nevertheless, sulfate radical was mainly produced by Fe(II)-activated PS at pH 3, while both Cu(I) and Fe(II) made important contributions to the generation of sulfate radical at pH 8. The bimetallic system was also highly effective in degrading other organic contaminants, such as phenol, diclofenac, reactive red 2 and orange G. This study might provide a promising idea based on Fe(II)-activated PS for degrading organic contaminants over a wide pH range.
研究领域:
环境科学
·
化学工程
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2023
·
IF 8.9
Mudassir Habib,Meesam Ali,Tehreem Ayaz,Ali Shan,Guilu Zeng,Zhengyuan Zhou,Shuguang Lyu
Rapid growth and industrialization have become a major threat to water contamination with carcinogenic chlorinated hydrocarbons such as trichloroethylene (TCE). Therefore, this study aims to assess the TCE degradation performance through advanced oxidation process (AOP) using catalyst FeS 2 in combination with oxidants persulfate (PS), peroxymonosulfate (PMS), and hydrogen peroxide (H 2 O 2 ) in PS/FeS 2 , PMS/FeS 2 , and H 2 O 2 /FeS 2 systems, respectively. TCE concentration was analyzed using gas chromatography (GC). The results found the trend for TCE degradation by the systems was PMS/FeS 2 >PS/FeS 2 >H 2 O 2 /FeS 2 (99.84, 99.63, and 98.47%, respectively). Degradation of TCE was analyzed at different pH ranges (3–11) and maximum degradation at a wide pH range was observed for PMS/FeS 2 . The analysis using electron paramagnetic resonance (EPR) and scavenging tests explored responsible reactive oxygen species (ROS) for TCE degradation and found that HO• and SO 4 − • played the most effective role. The results of catalyst stability showed PMS/FeS 2 system the most promising with the stability of 99, 96 and 50% for the first, second and third runs, respectively. The system was also found efficient in the presence of surfactants (TW-80, TX-100, and Brij-35) in ultra-pure water (89.41, 34.11, 96.61%, respectively), and actual groundwater (94.37, 33.72, and 73.48%, respectively), but at higher reagents dosages (5X for ultra-pure water and 10X actual ground water). Furthermore, it is demonstrated that the oxic systems have degradation capability for other TCE-like pollutants. In conclusion, due to its high stability, reactivity, and cost-effectiveness, PMS/FeS 2 system could be a better choice for the treatment of TCE contaminated water and can be beneficial for field application.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2019
·
IF 5.589
Wei Song,Ji Li,Zhuoyue Wang,Caixia Fu,Xiaolei Zhang,Jianpei Feng,Zhiliang Xu,Qi Song
The degradation efficiency of bisphenol A (BPA) was investigated in the process of persulfate (PS) coupled with dithionite (DTN) as a function of concentration of BPA, PS, DTN and solution pH. A simple response surface methodology (RSM) based on central composite design (CCD) was employed to determine the influence of individual and interaction of above variables and the optimum processing parameters. It is satisfactory of a quadratic model with low probabilities (<0.0001) at a confidence level of 95% to predict the BPA degradation efficiency. The model was well fitted to the actual data and the correlation coefficients of R 2 and R 2 -adj were 0.9270 and 0.8885, respectively. In addition, the obtained optimum conditions for BPA degradation were 1.79 μM, 131.77 μM, 93.64 μM for BPA, PS, DTN and pH = 3.62, respectively. It achieved a degradation efficiency >90% within 150 min. Moreover, the trapping experiment of active species demonstrated that SO 4 ·- and ·OH were the dominant species and natural water matrix showed an obvious inhibition effect on BPA degradation. The BPA degradation pathway was predicted based on GC-MS results in this study.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
Environmental Chemistry Letters
·
2019
·Vol. 17
·期 3
·1435-1439
·
IF 4.617
Chen Yiqun,Tong Yang,Liu Zizheng,Huang Li-Zhi,Yuan Jianping,Xue Yingwen,Fang Zheng
UV-activated persulfate (PS) systems have been widely employed to remove organic contaminants. However, the heavy use of persulfate may lead to secondary pollution. Here we proposed a novel UV/PS/sulfite oxidation process, in which sulfite would not only promote but also partially replace persulfate to produce sulfate radicals. We tested this system using Orange II as a model compound. Results show that the use of sulfite improves the degradation of Orange II. For instance, increasing the molar ratio of sulfite to persulfate in the range of 0.05–0.5 enhanced the removal efficiency by 21.7%. Compared to the UV/PS system, the presence of sulfite can achieve a 33.4% higher performance. We also found that the absence of dissolved oxygen remarkably inhibited the oxidation of Orange II. SO
·− 4
, SO
·− 5
and HO · were identified in the UV/PS/sulfite system, and SO
·− 4
and HO · should be primarily responsible for Orange II removal.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Yiqun Chen,Baitian Zeng,Liying Long,Qing Shao,Zizheng Liu,Feng Wu,Pengchao Xie
The ultraviolet/persulfate (UV/PS) process has attracted more and more attention for water treatment. However, it runs the risk of producing bromate in the presence of bromide ions. In this work, we propose a new strategy using sulfite to inhibit bromate formation. The results show that the addition of sulfite significantly reduced the formed bromate in the UV/PS system by 61.2% and 24.5% in 30 min and 120 min, respectively. Increasing sulfite dosage or pH could enhance bromate control. From the standpoint of reaction kinetics, sulfite is likely to inhibit bromate formation by reducing bromine radicals (Br ) back to bromide ions, the energy profile of which was quantified by density functional theory (DFT) calculations. In the UV/PS/sulfite system, the conversion of SO 3 − to HO was observed, indicating that sulfite also served as a source of reactive radicals. Moreover, sulfite apparently promoted the degradation of benzoic acid and phenol in a UV/PS system, showing advantages over other inorganic reductants. As a result, we discovered that sulfite could not only help control bromate formation in UV/PS but also improve the system’s oxidation capacity.
研究领域:
环境科学
·
化学工程
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Wei Song,Yuxin Zhou,Zhuoyue Wang,Ji Li,Xiaolei Zhang,Caixia Fu,Xing Du,Zhihong Wang,Wenhui Qiu
Advanced oxidation process (AOPs) is one of the most effective technologies for organic pollutants removal. In this study, diverse reactive species generation and enhanced sulfamethoxazole (SMX) degradation were investigated based on persulfate (PDS) activated by Fe 2+ &dithionite (DTN). When involving Fe 2+ &dithionite in PDS, SMX degradation efficiency reached 84 % within 30 min following a pseudo-first-order kinetic, which was higher than those in Fe 2+ /PDS (50.4 %) and Fe 2+ /O 2 /DTN (41.3 %). SO 4 •− and • OH were identified as dominant reactive species with a crucial role of FeSO 3 + based on quenching experiment and electron spin resonance (ESR). The contributions of SO 4 ·− , · OH, and other species to SMX degradation were 60.1 %, 33.9 %, and 6 %, respectively. In Fe 2+ /DTN/PDS system, SMX was effectively degraded under nearly neutral pH (5.0–9.0), with activation energy of 96.04 kJ·mol −1 . The experiments and density functional theory (DFT) calculation demonstrated that three functional groups (benzenesulfonamido, benzene ring, and oxazole ring) were attacked for SMX degradation. Moreover, acute toxicity to Vibrio fischeri has enhanced in the earlier degradation process due to the intermediates and weaken with the continuous reaction. This work not only provides a high-activity SO 4 ·− -AOP for refractory pollutant treatment with possible dual radical generation resources, but elucidated diverse reactive species formation with Fe 2+ &dithionite.
研究领域:
环境科学
·
化学工程
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Guilu Zeng,Rumin Yang,Mudassir Habib,Zhengyuan Zhou,Zhiqiang Xu,Qian Sui,Shuguang Lyu
Na 2 SO 3 and NaHSO 3 have been widely used as the source of SO 3 2− to participate in the reproduction of Fe(II) in iron-based advanced oxidation processes. In this work, CaSO 3 with low solubility was innovatively introduced and compared with Na 2 SO 3 and NaHSO 3 to investigate their effects on naphthalene (NAP) degradation in Fe(II)-activated peroxydisulfate (PDS) and peroxymonosulfate (PMS) processes. The results showed that CaSO 3 displayed a better performance due to its sustained-release of SO 3 2− , and NAP removal increased from 57.6% and 77.7% to 91.4% and 98.5% in PDS/Fe(II) and PMS/Fe(II) processes, respectively, with the addition of CaSO 3 . The enhancement mechanisms of CaSO 3 were illustrated by measuring the variation of iron and SO 3 2− concentrations and by quantitatively determining the production of reactive oxygen species (ROS). The dominant ROS generated in CaSO 3 -enhanced systems was confirmed by scavenging tests. Moreover, NAP degradation intermediates and pathways, as well as the toxicological properties of intermediates, were accordingly elucidated. Finally, CaSO 3 -enhanced systems had a wide application range of pH, and exhibited a great performance on the tolerance of various water matrixes. The significant removal of various contaminants in CaSO 3 -enhanced processes confirmed that these techniques are suitable for the remediation of organic contaminated groundwater.
研究领域:
环境科学
·
化学工程
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Su Yan,Lingling Zhan,Xiaoqing Meng,Dianzhan Wang,Xiaomeng Wang,Guanyu Zheng,Junhe Lu,Lixiang Zhou
Ultraviolet (UV)/peroxydisulfate (PDS) system has been employed for degrading organic pollutants in water, but the insufficient production of reactive species in the system limits the mineralization of organic pollutants. This study evaluated for the first time the effectiveness of integrating iron hydroxysulfates, including schwertmannite (Sch) and jarosite (Jar), with UV/PDS system for sulfamethoxazole (SMX) degradation in water. The optimal conditions identified for 40 μM SMX degradation were PDS 2 mM, photocatalysts 1 g L -1 and pH 3 in both of Sch/UV/PDS and Jar/UV/PDS systems. A synergetic effect between UV/PDS and Sch/UV processes was found in Sch/UV/PDS system with synergistic factor of 1.15, which drastically enhanced the production of reactive species ( OH and SO 4 •- ) and consequently improved SMX degradation and TOC mineralization. Additionally, schwertmannite exhibited higher photocatalytic activity than jarosite in UV/PDS system for both SMX degradation and TOC mineralization. In Sch/UV/PDS system, ≡Fe(OH) 2+ on schwertmannite can be efficiently photolyzed to ≡Fe 2+ and OH under UV irradiation with O 2 – generation, in which the produced reactive species contributed to a relatively small fraction of SMX degradation. More importantly, the regeneration of ≡Fe 2+ accelerated PDS activation to SO 4 •- / OH, which was responsible for the degradation of most SMX. However, the photoreduction of ≡Fe 3+ to ≡Fe 2+ on jarosite by UV irradiation was insignificant, thus leading to the poor PDS activation to SO 4 •- / OH and a lower SMX degradation rate. The degradation pathways of SMX in Sch/UV/PDS system were further proposed based on the identified degradation intermediates of SMX. Besides, schwertmannite exhibited a good adaptability in wide pH (2–9) range, good stability, and recyclability for catalyzing SMX degradation in UV/PDS system. Therefore, integrating schwertmannite with UV/PDS system is an attractive method for efficiently removing organic pollutants in water.
研究领域:
环境科学
·
水处理技术
✓ 已验证
DOI
高影响因子
Applied Catalysis O: Open
·
2024
·
IF 0
Zhe Zhang,Weiting Xiao,Yufei He,Dianqing Li,Xiaodong Zhao
During the manufacture of Al 2 O 3 , sulfate would be inevitably introduced when aluminum sulfate is used as raw material, but its effect has received little attention. In this work, Al 2 O 3 supports with different sulfate content were synthesized and used to prepare Pd/Al 2 O 3 catalyst. Sulfates in all samples exist as surface sulfate, and would be partially removed during the preparation process. Sulfate existing in Al 2 O 3 supports had little impact on the electric structure of Pd, but would partially block pores and also consume surface hydroxyl groups. As a result, higher sulfate content in support would lead to lower Pd dispersion in catalysts and slower reaction rate towards the hydrogenation of amyl-anthraquinone.
研究领域:
材料科学
·
催化化学
·
物理化学
✓ 已验证
DOI
危险品化学品经营许可证（带存储）