WATER RESEARCH
·
2023
·
IF 12.8
Wuming Wang,Zichong Zhou,Shunke Ding,Wenyuan Yang,Wei Jin,Wenhai Chu,Zuxin Xu
Ambroxol hydrochloride (AMB) and bromhexine hydrochloride (BRO) are classic expectorants and bronchosecretolytic pharmaceuticals. In 2022, both AMB and BRO were recommended by medical emergency department of China to alleviate cough and expectoration for symptoms caused by COVID-19. The reaction characteristics and mechanism of AMB/BRO with chlorine disinfectant in the disinfection process were investigated in this study. The reaction of chlorine with AMB/BRO were well described by a second-order kinetics model, first-order in both AMB/BRO and chlorine. The second order rate reaction constant of AMB and BRO with chlorine at pH 7.0 were 1.15 × 10 2 M −1 s −1 and 2.03 × 10 2 M −1 s −1 , respectively. During chlorination, a new class of aromatic nitrogenous disinfection by-products (DBPs) including 2-chloro-4, 6-dibromoaniline and 2, 4, 6-tribromoaniline were identified as the intermediate aromatic DBPs by gas chromatography-mass spectrometry. The effect of chlorine dosage, pH, and contact time on the formation of 2-chloro-4, 6-dibromoaniline and 2, 4, 6-tribromoaniline were evaluated. In addition, it was found that bromine in AMB/BRO were vital bromine source to greatly promote the formation of classic brominated DBPs, with the highest Br-THMs yields of 23.8% and 37.8%, respectively. This study inspired that bromine in brominated organic compounds may be an important bromine source of brominated DBPs.
研究领域:
环境科学
·
公共卫生
·
药学
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Ming Lei,Zhiying Wang,Yao Tang,Huimin Wang,Lihua Zhu,Heqing Tang
The use of palladium deposited TiO 2 (Pd/TiO 2 ) as catalysts yielded complete debromination of 2,2′,4,4′-tetrabromodiphenyl ether (BDE47) in isopropanol solution containing NaOH at 40 °C within 60 min. The final organic products were diphenyl ether and dibenzofuran. It was disclosed that two competing reduction paths (hydro-debromination and coupling-debromination) occurred over Pd nanoparticles . The hydro-debromination was dependent on the participation of active H atom species generated by catalytic transfer hydrogenation on metallic Pd. The coupling-debromination proceeded via the oxidative addition of Pd(0) to B r 2 C 12 H 8 OB r 2 ′ , leading to an transition state of B r 2 Pd II C 12 H 8 OB r 2 ′ , the reductive dissociation of which resulted in the elimination of Br − ions, producing a new transition state Pd 0 C 12 H 8 OB r 2 ′ − . A further oxidative addition of Pd 0 C 12 H 8 OB r 2 ′ − generated B r 2 ′ Pd II C 12 H 8 O − , and its final reductive elimination provided dibenzofuran, leading to the regeneration of Pd(0). The integration of the catalytic coupling and hydrogenation reaction on Pd nanoparticles greatly accelerated the removal of the halogenated organic pollutants.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2022
·
IF 4.778
Yang-Peng Lin,Xiao-Ying Huang,Ke-Zhao Du
Bromine is essential to scientific study and industrial application. However, the high toxicity, volatility and corrosivity of Br 2 increase the risk of leakage or explosion. Using solid materials to capture bromine gas can alleviate the leakage and explosion. Herein, X Br 3 ( X = Cs, C 8 H 20 N and C 16 H 36 N) polybromide compounds, were synthesized by the one-pot Br 2 -free solvothermal method. CsBr 3 can reversibly decompose and generate along with the release and capture of Br 2 gas, while Br 2 can be separated from aqueous solution in the form of Et 4 NBr 3 (Et = Ethyl) or Bu 4 NBr 3 (Bu = Butyl). CsBr 3 can release 42.89% Br 2 per molecular formula, which is the highest in reported crystalline materials so far. Bu 4 NBr can enrich Br 2 in water with approximately 73% yield through the hydrophilic-hydrophobic effect. Our study presents an alternative method for solidification and efficient recycle of Br 2 .
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2022
·
IF 8.91
Lu Wang,Yaqun Yu,Guoqiang Liu,Junhe Lu
Tetrabromobisphenol S (TBBPS), an emerging brominated flame retardant , can cause neurotoxic and cytotoxic effects to human physiology . In this study, the degradation of TBBPS in Co 2+ activated peroxymonosulfate (PMS) oxidation process was explored. In particular, brominated by-products formed during the degradation of the TBBPS were examined. It was found that TBBPS could be effectively removed in the Co 2+ /PMS oxidation process. The pseudo-first-order rate constants were 0.13 min −1 at 0.2 mM PMS and 0.5 μM Co 2+ initially. It appeared that TBBPS degradation occurred via and HO attacks, but played a dominant role. The presence of natural organic matter (NOM) greatly inhibited the transformation of the TBBPS, which can be explained by the scavenging of the radical species. β-Scission, debromination, and cross-coupling were identified as the main reaction pathways of TBBPS degradation in the Co 2+ /PMS system. Further oxidation and ring-opening of the intermediates generated brominated by-products including bromoform, monobromoacetic acid, and dibromoacetic acid. The formation of the brominated by-products increased gradually in approximately 48 h. But, the presence of NOM reduced the yields of the brominated -by-products. The findings of this study indicate that organic bromine contaminants can be effectively removed but lead to brominated by-products in the activated PMS oxidation process, which should be taken into consideration when -based oxidation technology is applied.
研究领域:
环境科学
·
化学工程
·
水处理
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DOI
PubMed
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2020
·Vol. 36
·期 6
·1234-1240
·
IF 1.063
Cui Ruizhi,Li Wu,Dong Yaping,Li Jun
The stable phase equilibria of quaternary systems LiBr-NaBr-MgBr 2 -H 2 O and LiBr-KBr-MgBr 2 -H 2 O at 298.15 K were studied by both experimental measurement(isothermal solution saturation method) and theoretical prediction(Pitzer model). The solubilities of the saturated solution have been determined experimentally and two stable phase diagrams and relevant water diagrams of the two quaternary systems were obtained. Results show that quaternary system LiBr-NaBr-MgBr 2 -H 2 O is hydrate II type as NaBr and NaBr·2H 2 O coexistence. Its phase diagram consists of only one invariant point, four univariant curves, and five crystallization fields. The quaternary system LiBr-KBr-MgBr 2 -H 2 O is a complex type as the double salt KBr·MgBr 2 ·6H 2 O formed. In addition to this double salt, the three single salts LiBr·2H 2 O, KBr and MgBr 2 ·6H 2 O also crystallize. In this paper, the solubilities of phase equilibria in above quaternary systems were also calculated by the Pitzer’s electrolyte solution model. All the needed parameters can be obtained from the literature or be fitted by experimental data. On the Basis of the experimental and calculated results, the phase diagram of the quaternary system was plotted for comparison. It shows that the calculation results are consistent with the experimental ones.
研究领域:
化学热力学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Jian Ao,Lingjun Bu,Yuwei Wu,Yangtao Wu,Shiqing Zhou
The formation of brominated disinfection byproducts (Br-DBPs) is an emerging issue in drinking water disinfection because its toxicity is tens to hundreds of times higher than that of chlorinated analogues and because of the widespread presence of bromide in source water. However, the mechanism and pathways of Br-DBPs formation remain unclear. In this study, we used glycine, alanine , and serine as model precursors and observed that brominated haloacetonitriles (Br-HANs) were more likely to be formed than brominated trihalomethanes. The results showed that there is not only one important way to HAN formation in the presence of bromide. We propose that organic bromamines, similar to organic chloramines, play a significant role in the formation of Br-HANs. Both the experimental and theoretical results confirmed that the decay of organic bromamines was faster than that of organic chloramines, which verified our assumption. The effect of the pH was investigated to further confirm the role of organic bromamines. In addition, we found that the formation of Br-HANs was significantly inhibited when monochloramine was used as a disinfectant, because the formation of organic bromamines was blocked. However, the formation of Br-HANs was promoted during the UV/chlorine process because of the faster decay of organic bromamines under UV photolysis. Overall, our study reveals the formation mechanism of Br-HANs and provides an alternative method to prevent Br-HAN formation.
研究领域:
环境科学
·
公共卫生
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2022
·
IF 3.119
Guo-Liang Nie,Rui-Zhi Cui,Wu Li
According to the composition characteristics of lithium, potassium, bromine, and other resources rich in the salt lake brine of the Qinghai–Tibet Plateau, the phase equilibria of the quaternary system LiBr-NaBr-KBr-H2O and its ternary subsystem LiBr-KBr-H2O at 323.15 K are studied by an isothermal dissolution equilibrium method. The solubility of each system in equilibrium solution at the corresponding temperature is measured, and the corresponding phase diagrams are drawn according to the phase equilibrium experimental data. The results show that there is no complex salt or solid solution in the ternary system LiBr-KBr-H2O at 323.15 K. The phase diagram contains one invariant point (E1), two univariate curves (AE1 and BE1), and two equilibrium solid crystallization regions (corresponding to LiBr·H2O and KBr), belonging to the simple cosaturated type. The quaternary system LiBr-NaBr-KBr-H2O also has no formation of complex salt and solid solution. The phase diagram contains two invariant points (F1 and F2), five univariate curves (E1F1, E3F1, F1F2, E2F2, and E4F2), and four equilibrium solid-phase crystallization regions (corresponding to LiBr·H2O, KBr, NaBr·2H2O, and NaBr). At the same time, to further explain the phase equilibrium relationship of each system at different temperatures and the change rule of each component, comparison and discussion are carried out.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Ziying Wang,Yisheng Shao,Naiyun Gao,Bin Xu,Na An,Xian Lu
Applying the highly oxidative sulfate radical ( SO 4 - · ) to pollutant degradation may cause it to react with the coexisting bromide (Br − ) to form undesired byproducts. This study investigated the transformation of Br − during the degradation process of a contaminant (diethyl phthalate (DEP)) via heat-activated persulfate (PS). Dibromoacetonitrile and bromoform formed with Br − and natural organic matter (NOM) in the solution, while only bromoform was detected without NOM. The formation of these brominated disinfection byproducts (Br-DBPs) can be ascribed to the reactions between the phenolic groups of DEP degradation intermediates or NOM and reactive bromine species (free bromine and radical bromine) generated through the oxidation of Br − by SO 4 - · . Br-DBPs were degraded by excessive SO 4 - · , which indicates that organic bromine is a temporary phase during the turnover of Br − . The time-dependent formation of organic and inorganic bromines suggests that Br − may have cycled several times between organic and inorganic forms before eventually turning into bromate. The bromate formation showed a lag phase before continuously increasing. Generally, increasing the temperature, PS dosage, and Br − and organic matter (DEP and NOM) concentrations increased the maximum concentration of Br-DBPs. Additionally, these reaction parameters facilitated bromate formation except for organic matter, whose inhibitory effect is probably due to the consumption of reactive species by organic matter and the generated superoxide anion. The total organic carbon concentration of the solution exhibited a relatively quick reduction followed by a slow decrease. These results highlight the potential risks of PS activation technologies and can help prevent such risks in actual practice.
研究领域:
环境科学
·
水处理
·
化学工程
·
污染物降解
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Feiyang Zhang,Penglei Xu,Xueqing Jin,Chen Wang,Qi Shen,Chunyan Sun
Polybrominated diphenyl ethers (PBDEs) have attracted increasing attention due to their biotoxicity and persistence. Herein, rapid degradation of decabromodiphenyl ether (BDE209) was achieved on bromine vacancies enriched BiOBr (BOB-V Br ) nanosheets, with a degradation rate for BDE209 under visible light irradiation (λ > 400 nm) exceeding 95 % within 6 min. The initial two minutes serve as an induction period, during which the Br vacancies were in-situ introduced into the BiOBr (BOB) nanosheets. By precisely controlling the duration of photoinduction, varying concentrations of Br vacancies were successfully generated on the surface of the BOB nanosheets. Consequently, an enhanced degradation rate of BDE209 was observed in direct correlation with the increased concentration of Br vacancies. BOB-V Br showed a remarkable selectivity of 74 % for meta- product (BDE207). This selectivity towards BDE207 surpasses that of other anionic vacancies, as oxygen, sulfur, and iodine vacancies. The in-situ generated Br vacancies help to accommodate the Br atom of BDE209 in atomic size and electronic structure, thus facilitating the activation of the C-Br bond and achieving rapid BDE209 debromination. This work provides a new insight for the treatment of organic halogenated pollutants by photocatalysts with homologous halogen vacancies.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2017
·Vol. 24
·期 29
·23219-23225
·
IF 2.741
Wang Lu,Ji Yuefei,Lu Junhe,Kong Deyang,Yin Xiaoming,Zhou Quansuo
The objective of this research was to compare the transformation of Br − and formation of brominated byproducts in UV/persulfate (PS) and UV/H 2 O 2 processes. It was revealed that Br − was efficiently transformed to free bromine which reacted with humic acid (HA) or dihydroxybenzoic acid resulting in the formation of brominated byproducts such as bromoacetic acids (BAAs) in UV/PS system. In contrast, no free bromine and brominated byproducts could be detected in UV/H 2 O 2 system, although the oxidization of Br − was evident. We presumed that the oxidation of Br − by hydroxyl radicals led to the formation of bromine radicals. However, the bromine radical species could be immediately reduced back to Br − by H 2 O 2 before coupling to each other to form free bromine, which explains the undetection of free bromine and BAAs in UV/H 2 O 2 . In addition to free bromine, we found that the phenolic functionalities in HA molecules, which served as the principal reactive sites for free chlorine attack, could be in situ generated when HA was exposed to free radicals. This study demonstrates that UV/H 2 O 2 is more suitable than UV/PS for the treatment of environmental matrices containing Br − .
Graphical abstract
研究领域:
环境科学
·
水处理工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2021
·
IF 2.694
Yun-Yun Gao,Xiao-Feng Guo,Lan-Rong Zhao,Shi-Hua Sang
The stable phase equilibria of the ternary system MgBr2 + SrBr2 + H2O at 288 and 308 K were studied with the isothermal dissolution equilibrium method. The compositions of solutions and solid phases have been determined and the equilibrium solid phases at the invariant points were identified with the aid of the X-ray diffraction method. The phase diagrams of this system at 288 and 308 K were both constructed in terms of experimental results. Two stable phase diagrams show that this system is hydrate type I at two temperatures without formation of a solid solution or complex salt. Both the phase diagrams are composed of one invariant point, two univariate curves, and two crystallization regions (SrBr2·6H2O and MgBr2·6H2O). The equilibrium solid phases of the invariant point at 288 and 308 K are both SrBr2·6H2O and MgBr2·6H2O, respectively. Combining the Pitzer single-salt parameters of MgBr2 and SrBr2 reported in the literatures, the unreported mixing ion-interaction parameters θMg,Sr and ΨMg,Sr,Br at 288 and 308 K were fitted with the measured values in this study using the Pitzer equations. The agreement between the experimental values and calculated results in the ternary system MgBr2 + SrBr2 + H2O at 288 and 308 K shows that the parameters fitted with solubilities are reliable.
研究领域:
化学
·
物理化学
✓ 已验证
DOI
高影响因子
WATER RESEARCH
·
2023
·
IF 12.8
Yifei Zhang,Zhechao Hua,Xuewen Zhang,Kaiheng Guo,Jingyun Fang
Solar photolysis of free chlorine (solar/chlorine) in bromide-containing water occurs under various scenarios, such as chlorinated reservoirs and outdoor swimming pools, and the formation of chlorate and bromate is an important issue in the system. We reported unexpected trends for the formation of chlorate and bromate in the solar/chlorine system. Excess chlorine inhibited the formation of bromate, i.e., increasing chlorine dosages from 50 to 100 μM reduced the bromate yield from 6.4 to 1.2 μM in solar/chlorine at 50 μM bromide and pH 7. The yield of bromate in solar/chlorine at 100 μM chlorine and 50 μM bromide in 240 min was 18.8% of that at 50 μM bromine only. The underlying mechanism was that HOCl can react with bromite (BrO 2 − ) to form HOClOBrO − , whose multi-step transformation finally formed chlorate as the major product and bromate as the minor product. This reaction overwhelmed the oxidation of bromite to form bromate by reactive species, such as • OH, BrO • and ozone. On the other hand, the presence of bromide greatly enhanced the formation of chlorate. Increasing bromide concentrations from 0 to 50 μM enhanced the chlorate yields from 2.2 to 7.0 μM at 100 μM chlorine. The absorbance of bromine was higher than that of chlorine, thus the photolysis of bromine formed higher levels of bromite at higher bromide concentrations. Then, bromite rapidly reacted with HOCl to form HOClOBrO − and it further transformed to chlorate. Additionally, 1 mg L − 1 NOM had a negligible effect on bromate yields in solar/chlorine at 50 μM bromide, 100 μM chlorine and pH 7. This study demonstrated a new pathway of chlorate and bromate formation in the solar/chlorine system with bromide.
研究领域:
环境科学
·
化学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）