CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Chen-Yan Hu,Yuan-Zhang Hou,Yi-Li Lin,Yan-Guo Deng,Shuang-Jing Hua,Yi-Fan Du,Chiu-Wen Chen,Chung-Hsin Wu
In this study, we investigated the degradation kinetics of a commonly used iodinated contrast medium, iohexol, by using heat-activated persulfate. The results indicate that the iohexol concentration can be effectively reduced with a removal percentage higher than 85% despite the long reaction time (2–3 h). The iohexol disappearance fitted well with the pseudo-first-order kinetic model. The persulfate consumption almost reached the maximum value during the initial 5 min of the reaction. Subsequently, persulfate was no longer consumed, which resulted in a decrease in the reaction rate. The pseudo-first-order rate constant of iohexol degradation significantly increased with temperature but decreased with an increase in pH from 5 to 9. The results of the quenching experiments performed using ethanol and tert-butanol indicate that the role of hydroxyl radicals was more important than that of sulfate radicals in iohexol degradation during heat-activated persulfate oxidation. However, without heat activation, persulfate did not react with iohexol. Therefore, the effect of pH on the HO· concentration dominated the effect of pH on iohexol degradation. High concentrations of bicarbonate (≥5 mM), chloride (≥1 mM), and dissolved natural organic matter (≥5 mg/L) inhibited the degradation of iohexol due to the consumption of sulfate and hydroxyl radicals. The mineralization percentage was only 3.8% (no considerable improvement) when the temperature was increased to 80 °C. The molecular structures of the intermediates contained iodine with molecular weights higher than 377 Da. Moreover, the generation of iodide was detected. The experimental results suggest that special attention should be paid to the risk of the formation of disinfection by-products in the subsequent chlorine disinfection process when treating natural water containing iohexol through heat-activated persulfate oxidation.
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
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Weiming Xiang,Qiuyi Ji,Chenmin Xu,Yang Guo,Yazi Liu,Dunyu Sun,Wenwu Zhou,Zhe Xu,Chengdu Qi,Shaogui Yang,Shiyin Li,Cheng Sun,Huan He
A novel Co 3 O 4 /g-C 3 N 4 /Bi 2 O 2 CO 3 (BCCN) photocatalyst with p-n/n-n heterojunction was synthesized through a solvent-thermal method. The degradation efficiency of 20 mg/L iohexol reached 94 % in 60 min ( k app =0.0417 min −1 ) in BCCN/light/PS system, which was 2.8 and 6.5 times higher than systems of BCCN/light ( k app =0.0150 min −1 ) and BCCN/PS ( k app =0.0064 min −1 ). The g-C 3 N 4 addition lowered conduction band of the prepared material to produce superoxide radicals, activate persulfate and further prevent the recombination of photoelectrons and holes. Superoxide radicals and singlet oxygens were dominant radicals for iohexol degradation. Besides, persulfate could act as electron acceptor to enhance efficiency of electron transfer. The interaction between sulfate, superoxide and hydroxyl radicals improved singlet oxygens production. Furthermore, theoretical calculation and liquid chromatography mass spectrometry were performed to analyze degradation pathway of iohexol in the system. Ultimately, the BCCN/light/PS system can provide a new method to degrade organic pollutants in aquatic environments.
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
Hui Cao,Yinhao Dai,Leliang Wu,Chengdu Qi,Linlin Hou,Dequan Zhang,Yao Li,Chenmin Xu,Huan He,Shaogui Yang
Advanced oxidation processes based on peracetic acid (PAA) activation have received more attention in water treatment recently. In this study, the degradation of iohexol (IOH, a classical iodinated X-ray contrast media) in the Co(II)/PAA system under neutral conditions, which mainly produced carbon-centric radicals, was investigated. Results showed that IOH decomposition follows the pseudo-first-order kinetic with a rate constant of 0.283 min −1 . Appropriately increasing concentrations of PAA or Co(II) could promote the removal of IOH, while elevating the dosage of H 2 O 2 inhibits the elimination of IOH in the Co(II)/PAA system. The IOH elimination was affected by pH, with the best response in pH between 5 and 7 in the Co(II)/PAA system. Additionally, low Cl − doses have negligible effects whereas high Cl − impeded the breakdown of IOH. Br − , I − , HCO 3 − , H 2 PO 4 − and humic acid suppressed the degradation of IOH. Removal of IOH was significantly inhibited in three selected real water samples. Furthermore, six IOH degradation pathways, including H-abstraction, amide hydrolysis, amino oxidation, deiodination reaction, hydroxylate and elimination reaction, were proposed on the basis of the liquid chromatography-tandem mass spectrometry , ion chromatography and DFT theoretical calculations (Frontier electron densities and fukui functions) results. Finally, the ECOSAR assessment showed that some degradation byproducts were much more toxic than IOH parent, but were much more biodegradable. Overall, this study indicates a potential risk when applying the carbon-centric radicals involved in PAA-based AOPs to remediate halogenated organic pollutants in water.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Chen-Yan Hu,Yuan-Zhang Hou,Yi-Li Lin,Yan-Guo Deng,Shuang-Jing Hua,Yi-Fan Du,Chiu-Wen Chen,Chung-Hsin Wu
The degradation rates and kinetics of one commonly used iodinated contrast medium, iohexol, were investigated and compared during ultraviolet (UV) photolysis, UV/H 2 O 2 and UV/ S 2 O 8 2 − advanced oxidation processes (AOPs). Results indicate that the iohexol degradation rate increased in the order of UV/H 2 O 2 < UV irradiation < UV/ S 2 O 8 2 − and followed pseudo-first-order kinetics. Increasing persulfate concentration significantly increased iohexol degradation rate, whereas increasing H 2 O 2 concentration caused reverse effect. Radical scavenging test results show that UV photolysis, OH and radicals all contributed to iohexol degradation during UV/ S 2 O 8 2 − , but OH was the main contributor during UV/H 2 O 2 and was consumed by excess H 2 O 2 . The kinetic models of iohexol degradation by both AOPs were developed, and the reaction rate constants with OH and were calculated as 5.73 (±0.02) × 10 8 and 3.91 (±0.01) × 10 10 M −1 s −1 , respectively. Iohexol degradation rate remained stable at pH 5–9 during UV irradiation and UV/H 2 O 2 , but gradually decreased at pH 5–7 and remained stable at pH 7–9 during UV/ S 2 O 8 2 − . The presence of anions displayed inhibitory effects on iohexol degradation during UV/ S 2 O 8 2 − in the order of Cl − > HCO 3 − ≫ S O 4 2 − . UV/ S 2 O 8 2 − AOP exhibited high degradation efficiency and stability on the basis of UV irradiation, which can be applied as a promising degradation method for iohexol. UV/ S 2 O 8 2 − AOP can effectively mineralize iohexol to CO 2 but promoted the generation of toxic iodoform (CHI 3 ), and the subsequent chlorination had the potential to reduce the content of disinfection by-products; therefore, further evaluation of possible environmental hazards is warranted.
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
Environmental Technology & Innovation
·
2023
·
IF 7.1
Ning Wang,Wenxuan Li,Tiantian Du,Man Li,Qian Zhao,Mei Li,Hongbo Wang,Li Song
Iohexol is one of widely used iodine X-ray contrast media, which are considered as iodine sources potentially yielding iodinated disinfection by-products in environmental waters. Therefore, it is necessary to remove iohexol from the source to ensure the safety of drinking water. This study investigated the effect of potassium ferrate on the degradation of iohexol via evaluating the influences factors, including reaction time, potassium ferrate dose, pH, humic acid, and aqueous coexisting ions. The results presented that a small dose of potassium ferrate could effectively remove iohexol in synthetic water samples in approximately 10 min. As pH increasing from 5 to 8, the removal efficiency of iohexol was improved from 31%–32% to over 90%. However, as applied to spiked lake water, potassium ferrate removed 76.3% (pH = 7) of iohexol and part of the dissolved organic matter. Additionally, humic acid, HCO 3 − , and PO 4 3 − were found inhibiting the degradation of iohexol, while SO 4 2 − had no significant effect. The reaction kinetics and degradation pathways iohexol were also studied to understand the removal mechanism of potassium ferrate. The rate law equation demonstrated a second-order reaction under the condition of pH = 9, and the rate constant was 0.515 M −1 s −1 . It was inferred that the possible pathway of potassium ferrate degrading iohexol included dehydrogenation reaction, amide hydrolysis reaction, degradation reaction, deiodination reaction, and hydroxyl addition reaction. Generally, potassium ferrate is promising in practical application of aqueous iohexol removal.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale Research Letters
·
2021
·Vol. 16
·期 1
·1-10
·
IF 4.703
Xie Jun,Zhou Zonglang,Ma Sihan,Luo Xian,Liu Jiajing,Wang Shengyu,Chen Yuqiang,Yan Jianghua,Luo Fanghong
X-ray computed tomography (CT) has been widely used in clinical practice, and contrast agents such as Iohexol are often used to enhance the contrast of CT imaging between normal and diseased tissue. However, such contrast agents can have some toxicity. Thus, new CT contrast agents are urgently needed. Owing to the high atomic number ( Z = 83), low cost, good biological safety, and great X-ray attenuation property (5.74 cm 2 kg −1 at 100 keV), bismuth has gained great interest from researchers in the field of nano-sized CT contrast agents. Here, we synthesized BiF 3 : Ln@PVP nanoparticles (NPs) with an average particle size of about 380 nm. After coating them with polyvinylpyrrolidone (PVP), the BiF 3 : Ln@PVP NPs possessed good stability and great biocompatibility. Meanwhile, compared with the clinical contrast agent Iohexol, BiF 3 : Ln@PVP NPs showed superior in vitro CT imaging contrast. Subsequently, after in situ injection with BiF 3 : Ln@PVP NPs, the CT value of the tumor site after the injection was significantly higher than that before the injection (the CT value of the pre-injection and post-injection was 48.9 HU and 194.58 HU, respectively). The morphology of the gastrointestinal (GI) tract can be clearly observed over time after oral administration of BiF 3 : Ln@PVP NPs. Finally, the BiF 3 : Ln@PVP NPs were completely discharged from the GI tract of mice within 48 h of oral administration with no obvious damage to the GI tract. In summary, our easily synthesized BiF 3 : Ln@PVP NPs can be used as a potential clinical contrast agent and may have broad application prospects in CT imaging.
研究领域:
医学影像学
·
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Shuohua Zhou,Weiming Xiang,Qiang Zhong,Shaogui Yang,Gancheng Zuo,Zhe Xu,Qiuyi Ji,Jijie Kong,Chenmin Xu,Bing Yang,Dunyu Sun,Yinhao Dai,Yazi Liu,Huan He,Shiyin Li
Sulphate radical (SO 4 · - ) -based advanced oxidation process (SR-AOP) is a promising sewage treatment technology. Reduced graphene oxide (rGO) supported Co 3 O 4 composites were synthesized by a hydrothermal method for the degradation of iohexol (IOH) in the rGO/Co 3 O 4 /peroxymonosulfate (PMS) system. Experimental results show that rGO/Co 3 O 4 possessed much better PMS activated ability than pure GO or Co 3 O 4 , which is ascribed to the summation of rGO and Co 3 O 4 . The efficiency of rGO/Co 3 O 4 composite, single GO and Co 3 O 4 nanocrystals for the degradation of IOH were 98.7%, 15.8% and 79.8% at 15 min, and their corresponding reaction rate constants ( k app ) were 0.21 min −1 , 0.0077 min −1 and 0.080 min −1 , respectively. The results of active species capture experiment and electron paramagnetic resonance (EPR) experiment, showed that singlet oxygen is the main active species, which is non-radical degradation. rGO is conducive to the electron conduction of Co 3 O 4 , thus improving the efficiency of PMS activation. The system is simple and efficient, which is an effective technology to remove IOH.
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
·
2024
·
IF 8.1
Xianfa Zhang,Mingzhao Huang,Zuoming Zhou,Xiaodan Zhao,Guohua Jing
Sulfite activation with iron-based heterogeneous activators is a promising technology for the removal of organic contaminants from water. However, the slow valence transformation of >Fe(II)/>Fe(III) compromises sulfite activation efficiency. Regarding that the oxygen vacancy (Vo) can modulate the charge distribution and thus enhance >Fe(II)/>Fe(III) valence transformation via rapid electron transfer, Vo-enriched γ-Fe 2 O 3 is constructed for sulfite activation (simplified as the γ-Fe 2 O 3 -Vo/sulfite system). The γ-Fe 2 O 3 -Vo/sulfite system exhibits excellent abatement performance for iohexol (IOX) with the efficiency as high as 90.2 % within 1 h of reaction at pH 8.5, in which sulfate radicals (SO 4 •− ) and hydroxyl radicals (HO • ) are the major species. Electrochemical and DFT calculations reveal that Vo-enriched γ-Fe 2 O 3 possesses lower electrical impedance and the concomitant higher electron transfer efficiency. According to a series of characterizations, the enhance >Fe(II)/>Fe(III) valence transformation is confirmed to contribute to sulfite activation via the regulation of the electronic structure by the Vo. In addition, the degradation pathways of IOX are proposed by analyzing the degradation products of IOX by UPLC-QTOF-MS. Finally, the effects of different influencing factors on the degradation of IOX and the cyclic performance suggest the system shows strong resistance to interference and reusability, exhibiting superior application potential.
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Chen-Yan Hu,Ye-Ye Zhu,Bin Xu,Tian-Yang Zhang,Yi-Li Lin,Cun Xiong,Qiang-Bing Wang,Dan-Dan Huang,Ling Xu
This study explored the degradation of an iodine X-ray contrast media , iohexol, under heterogeneous ozone-catalyzed oxidation by adding Fe 3 O 4 and 1-hydroxybenzotriazole (HBT). Results show that increasing the dosages of Fe 3 O 4 catalyst and ozone as well as solution pH were beneficial to the degradation of iohexol. The presence of low background humic acid (HA) concentration (≤10 mg/L) promoted iohexol degradation, but high HA concentration (≥20 mg/L) inhibited it. Adding HBT exhibited a similar effect on iohexol degradation as HA. The degradation rate constant of iohexol was calculated as 0.07108 min −1 in the Fe 3 O 4 /O 3 /HBT process ([HBT] = 5 μM) at pH 7.0, which was approximately 1.5 times higher than that in the Fe 3 O 4 /O 3 process (0.04533 min −1 ), and 4 times higher than that in the O 3 process (0.01742 min −1 ). Fe 3 O 4 /O 3 /HBT process was pH-dependent with high degradation efficiency of iohexol at pH 5 or 7. Singlet oxygen ( 1 O 2 ), hydroxyl radical ( OH ∙ ), and superoxide radical ( O 2 - ∙ ) have been identified in the Fe 3 O 4 /O 3 /HBT process, and the conversion of Fe 2+ to Fe 3+ was more obvious on the surface of Fe 3 O 4 compared to that in the Fe 3 O 4 /O 3 process. Transformation intermediates were identified, and the degradation pathways of iohexol were proposed. Overall, Fe 3 O 4 /O 3 could enhance iohexol degradation compared with ozone-only system, and adding trace HBT in Fe 3 O 4 /O 3 system can further enhance heterogeneous ozone-catalyzed process for rapid organic matter degradation.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Jing-Ping Zhu,Yi-Li Lin,Tian-Yang Zhang,Tong-Cheng Cao,Bin Xu,Yang Pan,Xi-Tong Zhang,Nai-Yun Gao
Iohexol can hardly be removed in conventional wastewater treatment processes due to its non-biodegradable and hydrophilic characteristics. In this study, a kinetic model was established to describe iohexol degradation in Fe (II)-activated persulfate system. The developed model can well predict iohexol degradation and evolution of sulfate radical with various initial iohexol and oxidant (ferrous iron and persulfate) concentrations under various water matrix. The rate constant of iohexol reacting with sulfate radical was calculated as (1.83 ± 0.10) × 10 9 M −1 s −1 . The effects of the two most common components in natural water bodies, chloride ion and natural organic matter (NOM) on iohexol degradation, were also studied. Both experimental data and model results showed that the low concentration of chloride ion promoted iohexol degradation while high concentration inhibited it, and NOM slightly inhibited iohexol degradation. Besides, radical quenching tests were employed to identify the main radicals formed in the system and further verified the model accuracy. The model is also capable of predicting the atrazine degradation with the correlation coefficients between the experimental data and predicted results above 0.97, suggesting the applicability of the established model for some other recalcitrant contaminant degradation in the Fe 2+ /PS system.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Qiuyi Ji,Kexun Du,Jiandong Zhu,Xiaoqian Ye,Hongjian Li,Xinying Cheng,Yazi Liu,Zhe Xu,Gancheng Zuo,Shiyin Li,Shaogui Yang,Limin Zhang,Huan He
The presence of iohexol (IOX) in the environment has attracted widespread attention. Acetic acid, hydrochloric acid , and nitric acid tailored self-assembled perylene diimides (P A , P C and P N ) were prepared and utilized in different visible-light-driven activation of peroxymonosulfate (PMS/Vis) systems for the degradation of IOX. As an electron acceptor, PMS can significantly hinder the recombination of photogenerated electron-hole pairs. The removal rate of 5 mg/L IOX by P C /PMS/Vis system reached 99.1% at 30 min, which was 2.0 times and 1.3 times higher than that of P A /PMS/Vis and P N /PMS/Vis system. The boosted oxidation activity with P C was due to the pH dependence of perylene diimide (PDI) self-assembly and the small amount of Cl − (0.56%) absorbed on P C , which can promote the transfer of electron-hole pairs, change the surface charge distribution and energy band position, and enhance π-electron conjugation. Based on density functional theory and electrostatic potential calculation, the Cl − adsorbed on the surface of PDI brings an effect on the electrostatic potential distribution. Furthermore, the built-in intermolecular electric field leads to accelerated charge transfer of PDI. In the P C /PMS/Vis system, holes, singlet oxygen and superoxide radical were perceived as the dominant contributors. The degradation of IOX carried out via pathways of amide hydrolysis, amino oxidation, hydrogen abstraction, deiodination reaction, and OH attack. This work provides a new method for the pollution control of IOX and scientific guidance for the tailored self-assembly of organic supramolecules.
研究领域:
环境科学
·
有机化学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2022
·
IF 5.999
Meng Ren,Na Li,Xuliang Jiang,Xianhe Liu,Aihua Zou
Hypothesis Iohexol (IOH) is a commonly used second-generation nonionic iodinated contrast agent. However, low gastrointestinal mucosal adherence and high downstream speed limit its application in intestinal Computed tomography (CT) imaging. We hypothesize that oral IOH delivery carriers composed of environmentally responsive materials enable the intestinal targeted delivery and prolong the intestinal residence time of IOH, enhancing the intestinal disease detection efficiency. Experiments An emulsion-filled alginate hydrogel system was developed as the intestinal targeting vehicle for IOH. The formulation optimization was determined by response surface analysis . After a thorough study of the physicochemical properties of this hydrogel matrix, the pH sensitivity and the ability to control release were investigated, followed by a vitro cell experiment evaluating its bioactivity and CT imaging capability. Findings This alginate hydrogel matrix was sparsely structured and rapidly released IOH at pH 7.4. Meanwhile the swelling degree was 4.4 times higher than that at pH 1.2, indicating a good selective responsiveness to the gastrointestinal simulated environment. It improved the CT visual contrast of A549 cells without affecting cell morphology, suggesting that it would be an effective oral administration for water-soluble nonionic contrast agents and a potential candidate for intestinal disease detection tools.
研究领域:
药学
·
医学影像学
·
生物医学工程
✓ 已验证
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）