JOURNAL OF HAZARDOUS MATERIALS
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2017
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IF 6.065
Yun Liu,Xin Hu,Yin Xu
To control acid mine drainage (AMD) at the source, a novel nanocomposite coating, based on SiO 2 nanoparticles as nanofiller embedded in γ-mercaptopropyltrimethoxysilane (PropS-SH) coating is introduced in this paper. The performance of the PropS-SH/SiO 2 (PSS) nanocomposite coatings with a different content of SiO 2 nanoparticles on pyrite oxidation inhibition was evaluated by electrochemical measurements and chemical leaching testing. The results of the investigations revealed that the addition of appropriate SiO 2 nanoparticles could greatly enhance the passivation efficiency of PropS-SH coating. The best coating was obtained from 3% (v/v) of PropS-SH solution with 2 wt% SiO 2 nanoparticles as this coating decreased pyrite oxidation by 81.1% (based on Fe release). In addition, the coating mechanism of PSS coatings on pyrite surfaces is presented in this paper.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
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2023
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IF 8.9
Jing Feng,Chengliang Zhou,Qian Yang,Zhi Dang,Lijuan Zhang
Inhibition of tailings oxidation could availably control the generation of acid mine wastewater from its source. Organosilanes serving as a high-efficiency inhibitor of the oxidation of pyrite, bring some problems including safety hazards caused by large amounts of organic solvents, difficult high-temperature curing, poor long-term properties, and so on. In our work, the PropS-SH/Ce (dbp) 3 (PS/Ce (dbp) 3 ) passivator with excellent passivation performance and self-healing properties was prepared by choosing 3-mercaptopropyltrimethoxysilane (PropS-SH) and dibutyl phosphate (Ce (dbp) 3 ) as the main passivating agent and the repair agent, respectively. We reduced the ratio of ethanol to water by adjusting the pH of the organosilane condensation and also achieved room-temperature curing by extending the curing time. Electrochemical and chemical leaching experiments results showed that the most appropriate addition of Ce (dbp) 3 was 0.2 wt% for enhancing the passivation performance of the passivated coating. In a 6-month chemical leaching experiment, the PS/Ce (dbp) 3 -0.2 passivation coating cured at room temperature showed a better passivation effect and maintained 90.55% and 78.54% of total Fe and SO 4 2− passivation efficiencies. The passivation and self-healing mechanisms were investigated by FT-IR, XPS , 29 Si NMR, and other characterization methods, which were as follows: silane formed a cross-linked mesh structure by Si–O–Si bonding, in which Ce (dbp) 3 was physically filled. And the Si–OH on the surface of the passivation film formed Fe–O–Si bonds with the hydroxyl groups on the surface of the pyrite, thus attaching to the surface of the pyrite and isolating the oxidation medium. When the passivation coating was locally damaged, the oxidation reaction caused a change in pH, which accelerated the dissolution of Ce (dbp) 3 in the passivation layer. Ce 3+ underwent a valence change and formed a CeO 2 precipitate, while dbp − could form a complex with Fe 2+ on the pyrite surface, both of which worked together to repair the broken passivation coating and prevent the oxidation reaction.
研究领域:
环境科学
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材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
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IF 4.9
Min Yu,Xiang Gao,Kanglu Feng,Juan Qiu,Chunchao Chen,Kangwei Gongsun,Changming Bu,Qing Zang,Zhaoyu Mao,Houyi Ma
The weak binding ability of silane to copper surfaces restricts its use in copper anticorrosion. In this study, the P–OH groups in etidronic acid (HEDP) were utilized to establish chemical bonds with copper and to react with 3-mercaptopropyltrimethoxysilane (PropS-SH), serving as a bridging mechanism to enhance the anchoring of silane onto copper surfaces. Moreover, the presence of HEDP promoted the condensation of silane, leading to the formation of a denser and thicker film with outstanding corrosion resistance. SEM results indicated that the thickness of the PropS-SH/HEDP film was about 125 nm, and defects at the copper–film interface were repaired. Electrochemical tests demonstrated that the PropS-SH/HEDP film exhibited remarkable corrosion resistance, achieving an anticorrosion efficiency of 99.95 %. Immersion testing showed that the PropS-SH/HEDP film was capable of withstanding immersion in a 3.5 wt% NaCl solution for 10 days, displaying a durability 5 times greater than that of the standalone silane film.
研究领域:
材料科学
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腐蚀与防护
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产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2022
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IF 10.753
Dejian Li,Xuemin Chen,Chenrui Liu,Jiang Tian,Feng Li,Yun Liu
In previous works, both tannic acid (TA) and organosilane-based passivators have been proven to possess good inhibition effects on pyrite oxidation, which could effectively prevent acid mine drainage (AMD) generation at the source. However, the hydrophilicity of TA passivation film and the complex coating process of organosilane-based passivators (high temperature conditions were required during the process carried out) may limit their further practical use. Therefore, to achieve the purpose of better coating treatment of pyrite under mild conditions, TA and γ-mercaptopropyltrimethoxysilane (PropS-SH) were introduced to synergistically passivate pyrite in this work. Electrochemistry tests and chemical leaching experiments both confirmed that PropS-SH-TA coated pyrite had better oxidation resistance than raw pyrite and single PropS-SH or TA coated pyrite. Additionally, the analyses of scanning electron microscopy (SEM) measurements and static water contact angle tests demonstrated that a scaly coating was formed on PropS-SH-TA coated pyrite surface, which may be the reason for the significant improvement of its surface hydrophobicity . Finally, the study on the film-forming mechanism of PropS-SH-TA composite passivator displayed that the benzoquinone derivatives formed by TA could copolymerize with PropS-SH through Michael addition or Schiff base reaction, which constructed a dense hydrophobic film on pyrite surface. The newly formed composite film could provide a better oxidation barrier for pyrite based on TA passivation film.
研究领域:
环境科学
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材料科学
✓ 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）