CERAMICS INTERNATIONAL
·
2014
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IF 2.086
Ran Liu,Tianyan Xue,Jing Song,Yu Wang,Tao Qi,Jingkui Qu,Ailing Du
The efficiency of silicon removal technology by acid leaching and flocculation during zirconium oxychloride octahydrate (ZrOCl 2 ⋅8 H 2 O) production has been improved. The optimum conditions of acid leaching were found to be as follows: transiton material, 300 g; HCl (6 mol/L), 600 mL; leaching time, 4 h; and leaching temperature, 100 °C. The nonionic polyoxyethylene lauryl ether (AEO9) was adopted as the flocculant. The optimum flocculation conditions were found to be as follows: temperature, 40 °C; flocculant amount, 10 ml (concentration 1%); time, 1 h. The zirconium oxychloride solution after purification contained 36 ppm SiO 2 and 160 g/L ZrOCl 2 . The polymerization and flocculation mechanisms of silicic acid were analyzed. Results of Fourier-transform infrared, scanning electron microscopy, nuclear magnetic resonance, and Brunauer–Emmett–Teller analyses showed the main transformation and properties of the products in the acid leaching and flocculation processes.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICA CHIMICA ACTA
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2020
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IF 5.977
Xuelin Dong,Yuxiang Xiong,Nan Wang,Zhou Song,Jie Yang,Xiumei Qiu,Lihua Zhu
The analysis of siliceous matrix samples may adopt a two-step pretreatment , which includes melting with ammonium hydrogen fluoride and redissolving with nitric acid . However, the residual of substrate silicon unfavorable to the determination of trace elements in the samples due to serious matrix effects. Here, a new digestion method using simultaneously both ammonium bifluoride and nitric acid under normal pressure was developed for high-purity quartz sand sample. The digestion pretreatment is a two step process: melting/dissolving with both ammonium bifluoride and nitric acid at 200 °C for 2 h, and evaporating the solution at 250 °C to dryness. As confirmed by XRD analysis, silicates in the sample were converted to (NH 4 ) 3 SiF 6 NO 3 in the melting/dissolving step. TGA analysis shows that the generated (NH 4 ) 3 SiF 6 NO 3 could be decomposed and evaporated completely at 250 °C, which ensured a complete removal of silicon by the followed evaporation of the solution at 250 °C. As a result, the followed ICP-OES and ICP-MS analysis needed a solution dilution of only 100 times for the determination of Ca, Mg, Al, Rb, Ba, REE and other trace elements. The new method was applied to the analysis of three certified reference materials, and the results were well consistent with the standard value with RSD% values between 0.62% and 9.73%. Therefore, this method can be applied to the analysis of trace elements in high purity silica-based samples, with the advantages of time-saving, small dilution factor (only 100 times) and low detection limit.
研究领域:
分析化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
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2023
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IF 4.5
Zhao-wang DONG,Xue-yi GUO,Yang XIA,Pei-dong LIU,Jin-xi QIAO,Zhong-chen LI,Han-ning LIU
Silicon in two types of upgraded titania slag (UGS) containing different components was removed using a low-temperature alkali solution and melt leaching. The effects of temperature, time, and NaOH solution concentration on desilication rate were investigated. Desilication in melt can lead to the loss of titanium in upgraded titania slag. After agitating at a speed of 600 r/min and 80 °C for 300 min, the silicon content in domestic slag decreased from 0.96 wt.% to 0.29 wt.%, and the leaching rate was 69.8% after leaching in 4 mol/L sodium hydroxide solution. Under the same conditions, the silicon content in imported slag decreased from 1.11 wt.% to 0.12 wt.%, and the desilication rate was up to 89.2%. The alloy powders obtained from the reduction of upgraded titania slag with magnesium were sintered to produce titanium alloy, and the alloy was characterized. It was determined that the Ti 5 Si 3 phase in the titanium alloy product was successfully eliminated. In addition, the two UGS materials and the chemical principle of desiliconization were analyzed using a thermodynamic software.
研究领域:
材料科学
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冶金工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
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2023
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IF 7
Jingjing Sun,Shangqing Chen,Yanan Dong,Junfeng Wang,Yi Nie
The removal of hardness and silicon in the reverse osmosis influent is urgently desirable in view of wastewater purification and reuse. However, the development of cost-effective method reducing the hardness and silicon to low level is challenging. Herein, the single step process and double step precipitation process were proposed, aiming at minimize the adverse effect of influent wastewater on reverse osmosis membranes. The optimal dosages of precipitants (FeCl 3 and MgCl 2 ) and the effects of pH values and time were investigated. In the double step process, the concentrations of total hardness and silicon reached the lowest values (11.0 mg·L −1 and 2.1 mg·L −1 ) by adding 400 mg·L −1 MgCl 2 and 300 mg·L −1 FeCl 3 . Subsequently, four schemes for the wastewater treatment were proposed, which scheme D using both FeCl 3 and MgCl 2 as precipitants obtained the lowest cost (1.20 $·t −1 ). This work could provide technological support for removing total hardness and silicon from industrial wastewater and industrial wastewater recycling.
研究领域:
环境工程
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废水处理
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
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2022
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IF 4.119
Jingjing Sun,Shangqing Chen,Junfeng Wang,Yi Nie
The reduce of the silicon concentration to low level (<5 mg·L −1 ) from the reverse osmosis brine wastewater is challenging and desirable for the maintain the membrane life and performance, as well as the wastewater treatment costs. This work focuses on the removal of silicon from the reverse osmosis brine wastewater by adding FeCl 3 into the plant wastewater for simultaneous Fe(OH) 3 formation and silicon adsorption. The effects of pH, FeCl 3 dosing concentration, reaction time, and temperature on the silicon removal ratio were investigated. It was demonstrated that the silicon removal ratio could reach up to 94% and its residual concentration was 3.2 mg·L −1 , which met the require of water quality in the reverse osmosis system. These results showed that Fe(OH) 3 could effectively be formed by adding FeCl 3 and realize the efficient silicon removal from the reverse osmosis brine wastewater, even when chloride ion (Cl - ), sulfate anion ( S O 4 2 - ) and nitrate ion ( N O 3 - ) were present. Moreover, the adsorption thermodynamics, kinetics and isotherms during the process of the adsorption of silicon from the wastewater by Fe(OH) 3 were studied. The calculated adsorption capacity of silicon could reach 612.74 mg·g −1 , which was much larger than those of reported adsorbents. These results showed that the silicon removal process was spontaneously exothermic and mainly controlled by the physical adsorption and the monomolecular layer adsorption. This simple and cost-effective method could be used for the silicon removal from different kinds of Si-containing wastewater.
研究领域:
环境科学
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废水处理
✓ 已验证
DOI
高影响因子
International Journal of Minerals Metallurgy and Materials
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2023
·Vol. 30
·期 6
·1038-1047
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IF 4.8
Wu Zhongxian,Tao Dongping,Tao Youjun,Jiang Man,Zhang Patrick
We analyzed a novel cationic collector using chemical plant byproducts, such as cetyltrimethylammonium bromide (CTAB) and dibutyl phthalate (DBP). Our aim is to establish a highly effective and economical process for the removal of quartz from collophane. A micro-flotation test with a 25 mg·L −1 collector at pH value of 6–10 demonstrates a considerable difference in the floatability of pure quartz and fluorapatite. Flotation tests for a collophane sample subjected to the first reverse flotation for magnesium removal demonstrates that a rough flotation process (using a 0.4 kg·t −1 new collector at pH = 6) results in a collophane concentrate with 29.33wt% P 2 O 5 grade and 12.66wt% SiO 2 at a 79.69wt% P 2 O 5 recovery, providing desirable results. Mechanism studies using Fourier transform infrared spectroscopy, zeta potential, and contact angle measurements show that the adsorption capacity of the new collector for quartz is higher than that for fluorapatite. The synergistic effect of DBP increases the difference in hydrophobicity between quartz and fluorapatite. The maximum defoaming rate of the novel cationic collector reaches 142.8 mL·min −1 . This is considerably higher than that of a conventional cationic collector.
研究领域:
矿物加工
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化学工程
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材料科学
✓ 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）