HYDROMETALLURGY
·
2018
·
IF 3.3
Qiaoling Xie,Tao Lin,Fuming Chen,Dandan Wang,Bo Yang
Sulphur-containing chitosan, a water-soluble derivative of chitosan, was synthesized by using chitosan and other reagents. This sulphur-containing chitosan was combined with chitosan to recover ultra-trace palladium in HCl medium. The effects of the chelating dosages, pH, chelating precipitation rate, initial Pd concentration and coexisting cations were systematically investigated via chelating precipitation experiments. Under the optimized conditions, greater than 95% of palladium was recovered from the HCl medium, with pH ranging from 2 to 5.5 and proper dosages of chitosan and sulphur-containing chitosan, which were related to the concentration of Pd(II) ions. In addition, the presence of coexisting cations (Cu 2+ , Ni 2+ , Fe 2+ , and Sn 2+ ) had no effect on the recovery rate of palladium. The recovery mechanism of palladium by chitosan and sulphur-containing chitosan was studied via molecular weight analyses, elemental analyses, FT-IR analyses and XPS analyses. The proposed chelating precipitation method was successfully applied to the recovery of ultra-trace palladium in HCl medium.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Peng Lu,Lyumeng Ye,Xianhui Yan,Jianhang Huang,Zhixiong Tang,Dongyao Chen,Chaoping Cen
It is challenging for catalytic oxidation of volatile organic compounds (VOCs) due to the existence of HCl in municipal solid waste incineration flue gases. A thorough probe into the deactivation mechanism is imperative but still lacking. Herein, the poisoning effect of gaseous HCl on a Ru-based catalyst for toluene catalytic oxidation was investigated. Toluene conversion and CO 2 selectivity decreased dramatically from 89.3 % and 93.8 % to 15.0 % and 8.0 %, respectively at 250 °C under HCl atmosphere. HCl led to a reduction of low-temperature redox properties, as well as a decrease of BET surface area, surface oxygen content and mobility, resulting in a loss of catalytic activity. HCl combined with active Ru and Mn, thereby restricting the electron transfer between Ru 4+ and Mn 2+ . Moreover, HCl could be oxidized by active oxygen species to form Cl• radical, which subsequently reacted with toluene oxidation intermediates, resulting in the generation of chlorinated compounds, such as chlorobenzene, dichlorobenzene, carbon tetrachloride, and benzyl chloride. These harmful chlorinated compounds predominantly deposited on catalyst surface. The protective role of H 2 O against HCl poisoning was mainly attributed to the competitive adsorption between H 2 O and Cl ions, the washing effect, and the promoting of intermediates oxidation and oxygen activation. It is noteworthy that during toluene oxidation in the presence of HCl + H 2 O, a detectable level of 0.048 ng I-TEQ/Nm 3 PCDD/Fs was observed in the off-gas.
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
CHEMICAL PHYSICS
·
2024
·
IF 2
Qian Liu,Panpan Xu,Qianqian Zhang,Guangming Han,Ling Li,Limin Zhou
A series of novel MIL-53(Fe)/CoWO 4 composites were synthesized by combining MIL-53(Fe) and CoWO 4 nanoparticles via solvothermal method. The structural characterizations showed that CoWO 4 nanoparticles were uniformly distributed on the surface of hexagonal bipyramid MIL-53(Fe). Combining XPS and Mott-Schottky plots, a Z-scheme heterojunction was formed between MIL-53(Fe) and CoWO 4 , resulting in a significant improvement in the electron-hole pair separation efficiency. UV–vis diffused reflectance spectra indicated that the optical arrange of MIL-53(Fe)/CoWO 4 composites were expanded to visible light. The photocatalytic degradation experiments under visible light irradiation showed that MIL/CWO-60 synergistically with PMS degraded 90.5 % of TC-HCl within 50 min. The XRD spectra of used and unused composites were identical, indicating good stability in four consecutive cycles. Electron paramagnetic resonance (EPR) and free radicals trapping experiment revealed that active species included O 2− , SO 4 − , h + , OH and 1 O 2 , and mechanism of the synergistic degradation of TC-HCl by MIL-53(Fe)/CoWO 4 composites and PMS was proposed.
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
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Shangchao Xiong,Jianjun Chen,Nan Huang,Tao Yan,Yue Peng,Junhua Li
The degradation of catalyst properties, rather than the deposition of NH 4 Cl, was the main reason for the deactivation of the MnCe low-temperature SCR (selective catalytic reduction) catalyst under HCl atmosphere. Cl ions prefer to be located at the oxygen vacancies around Mn cations on the MnCe surface. The adsorbed Cl ions could further promote the formation of oxygen vacancies. Therefore, the active Mn sites on the surface of MnCe would be quickly covered by Cl ions when HCl was present and thus promote the formation of Brønsted acid sites. However, the ionic NH 4 + adsorbed on the Brønsted acid sites of MnCe and MnCe − Cl were not fully utilized in the SCR reaction. Meanwhile, the reactivity of the coordinated NH 3 bonded with Lewis acid sites was significantly restrained by HCl due to the significant inhibition of the redox performance. Overall, HCl could obviously restrain the low-temperature SCR activity of MnCe.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ChemistrySelect
·
2024
·Vol. 9
·期 39
·e202402554
·
IF 1.9
Yu-chen Zhang,Xuan Liang,Rui Ding,An-lan Ji,Yu-han Wang,Ming-di Lei,Jie Fu,Jie Liu
Graphical The corrosion inhibition of NH 2 and OH substituted benzothiazoles on carbon steel in 0.5 mol/L HCl was investigated. 0.0010 mol/L 2-amino-6-hydroxybenzothiazole demonstrated efficient and persistent performance. The adsorption followed Freundlich-Langmuir isotherm. The OH at 6th position extended negative potential region and enhanced coordination activity, resulting in favorable orbital distribution for flat adsorption and feedback bonds. In the pickling process and acidizing program for oil wells, the acidic corrosion of metals is a problem that needs to be addressed. Various acid corrosion inhibitors have been studied and used to mitigate the acidic corrosion of carbon steel. In this paper, the corrosion inhibition of 2-aminobenzothiazole (2 N-BT), 2-amino-4-hydroxybenzothiazole (2 N4O-BT), and 2-amino-6-hydroxybenzothiazole (2 N6O-BT) on carbon steel in 0.5 mol/L HCl was investigated using electrochemical and quantum chemical methods. All three molecules exhibited corrosion inhibition effects. Compared to 2 N-BT, 2 N4O-BT and 2 N6O-BT showed less sensitivity to the environmental conditions and the surface state of the metal. Among them, 0.0010 mol/L 2 N6O-BT demonstrated the highest and most persistent corrosion inhibition, exhibiting a mixed inhibition mechanism with cathodic inhibition dominance. The adsorption of 2 N6O-BT on the carbon steel surface was found to be non-uniform, preferentially adsorbing at certain active sites on the surface, following Freundlich-Langmuir thermodynamic characteristics. It showed initial strongly adsorbed points and weakly adsorbed regions. With continued adsorption of 2 N6O-BT, the differences between strongly adsorbed points and weakly adsorbed regions decreased. The introduction of hydroxyl groups, especially in 2 N6O-BT, extended the negative potential region and enhanced the coordination activity of the molecule, generating the orbital distribution that was advantageous to flat adsorption and the formation of feedback bonds. This provided a molecular structural basis for the excellent corrosion inhibition properties of 2 N6O-BT.
研究领域:
材料科学
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电化学
·
量子化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Fengting Li,Yi Zhou,Zhikun Wang,Wentao Qu,Huiling Su,Miantuo Li,Nannan Cui,Shuangqing Sun,Yu Fu,Songqing Hu
Carbon dots (CDs) have been studied as eco-friendly corrosion inhibitors for metals. However, the mechanisms behind their effectiveness are not fully understood. We developed a cost-effective and environmentally friendly method to synthesize Ce-doped CDs (CeCDs) using urea, ammonium citrate, and cerium nitrate. By optimizing the Ce doping concentration to 200 μg/L, we achieved a high corrosion inhibition efficiency. When tested in 1 M HCl, CeCDs at 200 mg/L showed 80 % inhibition, while ionic liquid-modified CeCDs (IL-CeCDs) demonstrated an even higher efficiency of 95.35 % on N80 steel. Both CeCDs and IL-CeCDs adsorb onto metal surfaces through a combination of physical and chemical interactions, inhibiting corrosion mainly by affecting cathodic reactions. Among different Ce-doped CDs, CeCD3N, which has a single Ce atom doping, exhibited the highest molecular reactivity, allowing it to interact more effectively with the Fe surface. Further analysis revealed that Ce doping reduces the energy gap of CDs, enhancing their reactivity. Molecular dynamics simulations showed that CeCD3N adsorbs more strongly and forms a closer inhibitor film on the Fe surface compared to other Ce-doped CDs, making it an effective corrosion inhibitor.
研究领域:
材料科学
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腐蚀与防护
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2022
·
IF 8.634
Yanting Lv,Zhengyu Chen,Huan Wang,Yongcang Xiao,Rongxin Ling,Murong Gong,Weiqi Wei
In this work, an HCl-catalyzed ethylene glycol (EG) pretreatment was exploited for promoting sugar release from sugarcane bagasse (SCB). The results showed that the combination of HCl and EG could remove the xylan (∼100.0%) and lignin (∼61.3%) in SCB together, which finally resulted in the pretreated substrate having a good efficacy for follow-up enzymatic hydrolysis . The maximum glucose yield of this work was 93.9% and obtained after pretreatment at 130 °C for 60 min with 0.5% HCl and 72 h enzymatic digestion. The analysis of various pretreated or un-pretreated SCB indicated that the changes of surface morphology and internal compositions of SCB were the mainly reasons for its hydrolysis efficiency enhancement. The addition of Tween 80 into hydrolysis process could remarkably shorten hydrolysis time and cellulase dosage from 72 h to 36 h and 20 FPU/g substrate to 10 FPU/g substrate, respectively, meanwhile maintaining a relatively high glucose yield (91.4%).
研究领域:
生物技术
·
可再生资源工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Yong Lu,Huixia Feng,Hou Xia,Wu Hai Xia
Polyaniline has a wide application in the field of corrosion protection, the poor solubility of polyaniline limited its application as a corrosion inhibitor. Water-soluble carboxymethyl cellulose -polyaniline composites was synthesized by chemical oxidation polymerization in a mild way without other inorganic or organic acids added. Corrosion inhibition performance of composites was evaluated for Q235 steel corrosion in 1 M HCl corrosive solution using weight loss and electrochemical measurements at various concentrations. The results show that carboxymethyl cellulose -polyaniline composites exhibit good inhibition properties and the remarkable increase in inhibition efficiency, i.e., 94.24% is achieved while the maximum concentration of the experiment is 1000 ppm. The composites in corrosive solution suppress the cathodic hydrogen evolution reactions and anodic metal dissolution of the substrate. Adsorption of the inhibitor on the steel surface follows a Langmuir adsorption isotherm.
研究领域:
材料科学
·
腐蚀与防护
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·Vol. 48
·期 7
·3064-3079
·
IF 2.7
Miantuo Li,Fengting Li,Jianwen Hu,Nannan Cui,Huiling Su,Lizhi Li,Zhikun Wang,Shuangqing Sun,Songqing Hu
Three chitosan ionic liquid type Schiff bases (CS-IL-SBs) were synthesized by grafting three aldehydes (vanillin, cinnamaldehyde, and pyridine-4-carboxaldehyde) on CS-IL (chitosan grafted with p-toluene sulfonic acid) through a Schiff base reaction. Thermogravimetric analysis indicated that the thermal stability of CS was enhanced by the modification of IL and Schiff base groups. All CS-IL-SBs present a non-crystalline structure as analyzed using X-ray diffraction technique and have a positively charged surface in solution for improved dispersion stability as analyzed using zeta potential testing. A corrosion inhibition performance investigation using electrochemical and mass loss methods was undertaken, which were supported with surface analysis and computational studies. All the CS-IL-SBs act as effective corrosion inhibitors obeying Langmuir adsorption isotherm containing both chemisorption and physisorption for N80 steel in 15% HCl solution. Among them, CS-IL-Vin (grafted by vanillin) exhibits a maximum inhibition efficiency of 83.66% at 400 mg L−1. The analysis of the corroded metal surface via scanning electron microscopy depicts a considerably smooth morphology in the presence of adsorbed CS-IL-SBs. Contact angle tests indicated that the water-repellent ability of the metal surface was increased by the addition of CS-IL-SBs. Density functional theory calculations indicated that the active regions of CS-IL-SBs are mainly distributed in –SO3−, benzene rings, and Schiff base groups. Molecular dynamics simulations show that CS-IL-SBs are parallelly adsorbed on the metal surface to form a stable protective film. CS-IL-Vin shows the best performance among the three CS-IL-SBs, which was selected to be compounded with aided inhibitors with different electrical properties. When CS-IL-Vin was compounded with negatively charged 3-carboxybenzene sulfonate in a ratio of 1 : 3, corrosion inhibition efficiency was the highest, reaching 93.45%.
研究领域:
材料科学
·
电化学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2016
·
IF 5.393
Ting Liu,Lucheng Xue,Xin Guo,Jia Liu,Yu Huang,Chuguang Zheng
The reaction mechanisms of a mixture gas of HCl, O2, and SO2 in Hg0 adsorption on α-Fe2O3(001) surface are clarified by a group of adsorption experiments and theoretical calculations based on the density functional theory. The role of O2 in removing Hg0 is greatly influenced by the reaction temperature, meanwhile, the O atom coverage could affect the adsorption performance of Hg0. The dissociated O2 competes with the active sites of Cl species on Fe surface at low temperature, however, at medium temperature HCl and O2 could simultaneously facilitate the Hg0 transformation. Combined with the theoretical calculations, the role of SO2 and the probable pathways in removing Hg0 are discussed. Lower concentration of SO2 as well as HCl could dissociate on α-Fe2O3(001) surface, and the intermediates combine with gaseous Hg0, forming mercury–sulfur, mercury–chlorine compounds, and so forth. In addition, the different concentrations of SO2 are also discussed, and the corresponding X-ray photoelectron spectroscopy analysis on contrasted samples is conducted to research the morphological characterization, providing a reliable basis for judging the probable pathways of Hg0 transformation.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Chuan Lai,Hongxia Yang,Xiaogang Guo,Xiulan Su,Lvshan Zhou,Lei Zhang,Bin Xie
The new organic corrosion inhibitor of 2-( p -bromobenzylthio)-1 H -benzimidazole (Br-BBD) was synthesized in this work. After prepared, the adsorption and corrosion inhibition performance of Br-BBD for Q235 steel in HCl solution were studied using EIS, SEM, polarization measurement and WLM (weight loss measurement). The results exhibit that Br-BBD acts as an excellent corrosion inhibitor for Q235 steel in HCl solution, and the inhibition efficiency can reach up to 98.07% when the Br-BBD concentration is 50 mg L -1 in 1.0 M HCl at 25°C. In addition, the adsorption of the mixed-type inhibitor of Br-BBD on Q235 steel surface obey Langmuir adsorption isotherm, which is governed by spontaneous chemisorption mechanism.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
ANTI-CORROSION METHODS AND MATERIALS
·
2025
·
IF 2.6
Xiong Zhao,Junying Zhang,Jing Li,Ping Qiu
Purpose AQs3This study aims to explore the corrosion inhibition performance and mechanism of pyridine derivatives on the corrosion of N80 steel in a 0.5 M HCl solution using electrochemical experiments. Design/methodology/approach This study evaluates the corrosion performance of three pyridine derivatives (4-hydroxypyridine [OI], 4-aminopyridine [NI] and 4-mercaptopyridine [SI]) as organic corrosion inhibitors for mild steel in a 0.5 M HCl using potentiodynamic polarization, electrochemical impedance spectroscopy and atomic force microscopy. The bonding mechanism between the reactive groups of the inhibitor molecules and the metal surface is analyzed using theoretical calculations. Findings The corrosion inhibition efficiency of the studied inhibitors on mild steel follows the sequence: SI > NI > OI. The bonding mechanism between the reactive groups of the inhibitor molecules and the metal surface is analyzed using theoretical calculations. It is found that the reactive group changes the charge transfer and the bonding strength of the corrosion inhibitor to the metal surface, which affects the corrosion inhibition performance. Originality/value This study provides valuable insights into the role of electron transfer in the interaction between the inhibitor and the metal surface, thereby contributing to the development and design of more effective and economical corrosion inhibitors.
研究领域:
材料科学
·
腐蚀与防护
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）