SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
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IF 8.1
Dewen Zhou,Qinglong Luo,Guoliang Nie,Mingzhe Dong,Xiao Du,Haining Liu,Zhijian Wu,Jun Li
High-quality, low-chloride zinc borate is a low-smoke, non-toxic and environmentally friendly flame retardant with improved electrical properties for printed circuit board (PCB), so it can be used as a new type of flame retardant to replace brominated flame retardants. However, the chlorine content of zinc borate itself is high, and long-term use of zinc borate circuit boards will cause leakage and may cause a fire. To solve this problem, commercially available zinc borate (analytically pure) with a high chlorine content was used for the study. The presence of chloride ions in zinc borate was determined by X-ray photoelectron spectroscopy (XPS) and point of zero charge (PZC) and found to be mainly in the form of soluble salts and electrostatic adsorption. Based on the existing form of chloride ions, the synergistic technology of electrodialysis and washing with Na 2 CO 3 solutions was used to remove most of the chloride ions from zinc borate, and the removal effect was up to 94.03%. The optimal process was optimized by the reaction surface curve method, the separation kinetics and electrical properties were investigated, and the membrane lifetime was evaluated. Zinc borate can be used as a flame retardant in printed circuit boards after contrast treatment. This study provides an important reference and guide for the removal of impurity ions from other inorganic flame retardants. In addition, it provides technical support for the production of high-quality zinc borate flame retardants.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2018
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IF 4.513
Zaizhi Liu,Huiyan Gu,Lei Yang
An ionic liquid-based homogenate-ultrasound-synergistic technique was proposed to simultaneously extract dihydroquercetin and arabinogalactan from Larix gmelinii stumps. The appropriate extraction solvent of [C 2 mim]Br was screened from thirteen kinds of imidazolium-based ionic liquids. The optimal conditions for the proposed method obtained by response surface methodology were a [C 2 mim]Br concentration of 0.87 mol/L, IL-HUSE time of 24 min, liquid/solid ratio of 14 mL/g, and ultrasound power of 240 W. Under these conditions, the satisfied extraction yields were 53.09 ± 2.24 mg/g for dihydroquercetin and 152.48 ± 5.78 mg/g for larch arabinogalactan. Validation studies suggested that the improved method was capable of extraction of dihydroquercetin and arabinogalactan from L. gmelinii stumps. High extraction yields of dihydroquercetin and arabinogalactan obtained from the recycled [C 2 mim]Br indicated that the proposed method is a highly efficient technique. The present research indicates that the improved process shows promising prospects for application to the preparation of bioactive substances from plant materials.
研究领域:
植物化学
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天然产物开发
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DOI
高影响因子
RSC Advances
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2019
·Vol. 9
·期 1
·450-459
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IF 3.049
Zhikai Wei,Peng Li,Muhammad Hassan,Pu Wang,Cong Xu,Long-Fei Ren,Yiliang He
Photovoltaic wastewater contains a large amount of thiourea that cannot be directly treated by biological methods because of its biotoxicity. In this study, a novel O3/H2O2 + BiPO4/UV synergy technique was used as a pre-treatment process to degrade thiourea. The effects of H2O2 and catalyst loading were investigated, and the transformation pathway of thiourea was predicted based on the intermediates detected by UPLC-Vion-IMS-QToF. The synergy technique degraded 89.14% thiourea within only 30 min, and complete degradation occurred after 150 min. The TOC removal of O3/H2O2 + BiPO4/UV was 1.8, 1.5, and 1.9 times that of O3/H2O2 and BiPO4/UV/H2O2 single processes and O3/H2O2 + UV process, respectively, which was due to the synergy between H2O2 residues and BiPO4. In addition, thiourea was mainly degraded by ·OH into thiourea dioxide and melamine (polymerized by other intermediates) and then further degraded into biuret and methyl carbamate by the holes of BiPO4, followed by complete mineralization into H2O and CO2. These results confirm that the O3/H2O2 + BiPO4/UV synergy technique is a promising option for the degradation of thiourea.
研究领域:
环境工程
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水处理
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化学工程
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产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Muhammad Akram,Zahira Bano,Seerat Ul Ain Bhutto,Jingwen Pan,Ahmed Uddin,Muhammad Zaheer Afzal,Linrui Li,Mingzhu Xia,Fengyun Wang
This study was conducted to address water pollution concerns entwined with electroless nickel plating (ENP) industry. Its principal endeavor centers on the development and application of an innovative single-compartment technique to proficiently treat spent ENP baths. The research demonstrated the recovery of Nickel (Ni) from wastewater through synergistic interactions between electrocatalytic oxidation and electrodeposition processes. Electrochemical tests used a direct current power supply in constant current mode, with the positive pole on IrO 2 /Ti mesh and negative pole on stainless steel. Zero-valent nickel recovered on the electrodes was conclusively identified via SEM, XRD, and EDS analyses. This work carefully examined the impact of initial pH, initial Ni ion concentration, and current density (CD) on electrochemical recovery efficiency. The findings suggest that higher current densities positively influence the Ni recovery ratio. Additionally, through meticulous experiments, the viability of this approach for treating spent ENP baths has been confirmed. An impressive 98.88% recovery of Ni was achieved under specific conditions: CD 4.5 mA cm −2 , experimental time 180 min, pH 4.5, electrodes spacing 1.5 cm, temperature 55 °C, and a dilution factor 10 times. The study demonstrated the process for Ni recovering from ENP wastewater through direct oxidation and subsequent decomposition, leading to liberation of free Ni ions. The recovered substance, identified as zero-valent nickel, adheres to the electrodes. The method employed in this research is described by its cost-effectiveness, user-friendliness, and low energy consumption. As a result, this study makes valuable contributions to both wastewater remediation and the sustainable utilization of Ni resources.
研究领域:
环境科学
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废水处理
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电化学
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材料科学
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可持续资源管理
✓ 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）