INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Zheng Zhang,Shuai Tang,Kai Ge,Kangjun Wang,Yuanhui Ji
The scaling phenomenon poses a great challenge for industrial production because of its widespread presence and the complex scaling process. Hence, we report a novel terpolymer (PIA-SAS-AM) scale inhibitor with high efficiency to obstruct the formation of calcium sulfate. Furthermore, the scale inhibition performance and mechanism were further evaluated and systematically investigated. Herein, the various influence factors (monomer ratio, polymerization temperature, initiator content, etc.) on scale inhibition were discussed in detail. By various characterization methods, the terpolymer scale inhibitor was identified, consistent with the expected structure. Based on the static scale inhibition method, the performance of the copolymer on the control of the CSD (calcium sulfate dihydrate) scale was also explored under different external environments (copolymer concentration, retention temperature, calcium concentration, etc.). Especially, the scale inhibition efficiency of CSD reached nearly 100% when the concentration of the copolymer was 16 mg/L. Additionally, the prepared terpolymer scale inhibitor has great aqueous solubility, salt, and heat resistance. This work provides novel insights into inhibiting crystal scaling and offers further guidance on polymer scale inhibitor design.
研究领域:
材料科学
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化学工程
·
高分子化学
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产品关联
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2024
·
IF 4.4
Jing Zhou,Yingde Xu,Yifan Wang,Shengli Zhu,Zhenduo Cui,Yanqin Liang,Hui Jiang,Xiang Ge,Zhaoyang Li
Calcium sulfate (CS) is a commonly used filling material for bone defects; however, its mechanical strength requires further enhancement. The hydration process of CS significantly influences its mechanical properties. This study aims to improve these properties by incorporating carboxymethyl cellulose (CMC) and silicon dioxide (SiO 2 ) to optimize the hydration process of calcium sulfate hemihydrate (CSH). After adding CMC, the content of CSH in the hydrated material significantly increased, while the amount of calcium sulfate dihydrate (CSD) decreased. In the XPS analysis, the Ca 2p peaks exhibited notable shifts following the addition of CMC and SiO 2 . The mechanisms by which the hydration process influences mechanical strength were further analyzed. It was found that Ca 2+ ions from CSH chelated with CMC, while SiO 2 formed Si-O-Ca bonds with Ca 2+ , both affecting the hydration process of CSH in different ways. The optimal addition amounts of CMC and SiO 2 were both determined to be 1.5 %. Compared to pure CS, the mechanical properties of the experimental group increased by 520 %, rising from 4.28 MPa to 22.25 MPa. Additionally, the injectivity and erosion resistance were improved. All materials showed no cytotoxicity in hemolysis and cell experiments. In summary, this study demonstrates how the mechanical strength of CS can be enhanced by incorporating CMC and SiO 2 to influence its hydration process.
研究领域:
材料科学
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生物材料
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骨科
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生物医学工程
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DOI
高影响因子
HYDROMETALLURGY
·
2017
·
IF 2.605
Xiaobin Li,Leiting Shen,Qiusheng Zhou,Zhihong Peng,Guihua Liu,Tiangui Qi
Aiming to treat scheelite concentrate for producing ammonium paratungstate efficiently and cleanly, the conversion of scheelite to H 2 WO 4 and CaSO 4 ·nH 2 O in H 2 SO 4 solution was firstly studied in this work. The results show that H 2 SO 4 concentration, temperature, time, stirring speed, and particle size affect the conversion efficiency. Moreover, this work reveals that solid H 2 WO 4 layer on the surface of CaWO 4 particles forms and develops from thickness and looseness to thinness and denseness with increasing H 2 SO 4 concentration, and thus hinders the conversion of CaWO 4 to H 2 WO 4 , whereas CaSO 4 ·nH 2 O almost does not deposit in the layer. Meanwhile, H 2 WO 4 layer on CaWO 4 surface is resulted by isopolytungstate ions diffusion-tungstic acid deposition in diffusion layer. Additionally, the performance of separating H 2 WO 4 from CaSO 4 ·nH 2 O by leaching the converted product with aqueous ammonium carbonate solution was examined, showing that the converted product has an excellent leachability of tungsten in aqueous ammonium carbonate solution at ambient temperature with WO 3 leaching efficiency of about 99%. This work has the potential to develop a novel technique for tungsten extraction from scheelite concentrate under atmospheric pressure, bypassing the conversion of Na 2 WO 4 to (NH 4 ) 2 WO 4 .
研究领域:
冶金学
·
化学工程
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DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Leipeng Ji,Zhisong Liu,Zihao Li,Wenjun Huang,Haomiao Xu,Zan Qu,Naiqiang Yan
The gypsum from flue gas desulfurization or the neutralization (D/N gypsum) process of acid wastewater, is an industrial by-product in nonferrous metal smelters. The S and Ca sources of D/N gypsum have significant application prospects. However, the S(IV) reduction is difficult due to the electronic inactivity of CaSO 4 and the stability of the S-O band. Our experimental results indicated that the start-up temperature of CaSO 4 reduced by CH 4 is 900 ℃. However, adding H 2 S gas with a H 2 S/CaSO 4 (S/Ca) ratio of 0.2, the start-up temperature of CaSO 4 reacted with CH 4 decreases to 650 ℃. With the increase of the S/Ca ratio from 0.04 to 0.2, the yield of CaS increased to 94.97%, and the selectivity toward CO 2 formation increases to 71.67%. In-situ diffuse reflectance Fourier transformations spectroscopy (in-situ DRIFTs) results indicate that adding H 2 S generates the new sulfide groups on the surface of CaSO 4 , resulted from the S(-II) in H 2 S changing the distribution of valence electrons of O and activating O. Moreover, the density functional theory (DFT) calculation results exhibit that the activation energy for the first O dissociation decreases to 2.89 eV in the presence of H 2 S. Furthermore, H 2 S optimized the reaction path of CH 4 and improved the selectivity toward CO 2 formation. Comparing to 1000 ℃ without H 2 S, under 800 ℃ with H 2 S, the consumption of CH 4 reduces to 45%, and the CO 2 selectivity increases to 71.67%. Thus, we have developed a method of CaSO 4 low-temperature reduction and provide a theoretical basis for its application in engineering.
研究领域:
化学工程
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTAL RESEARCH AND TECHNOLOGY
·
2025
·
IF 1.9
Xingchao Fan,Bangfu Huang,Zhe Shi,Linjing Yang,Fu Yuan,Keying Zhu,Daoping Zhan
Aiming at the problems of low crystallization rate and uneven particle size during evaporative crystallization of ammonium sulfate mother liquor (a by-product of ammonia desulfurization of sintered flue gas), this study investigated via orthogonal tests the effects of evaporation temperature, pH, stirring rate, and calcium sulfate addition on crystallization amount, average particle size, and coefficient of variation (C.V.). The results showed: For crystallization amount, the influence degree was evaporation temperature>pH>stirring rate>calcium sulfate addition; for average particle size, it was stirring rate>pH>evaporation temperature>calcium sulfate addition; for C.V. value, it was stirring rate>pH>calcium sulfate addition>evaporation temperature. Crystal morphologies included hexahedral, columnar, lamellar, etc., with aggregation under some conditions. Crystals contained calcium, nitrogen, oxygen, and sulfur elements(Ca, N, O, S); Ca content increased with calcium sulfate addition. Ammonium sulfate crystals' diffraction peaks matched pure ammonium sulfate, with the highest peaks at pH 5.0, 250 rpm stirring, 3500 mg·L −1 calcium sulfate, and 333.15K.
研究领域:
化学工程
·
结晶学
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环境工程
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无机化学
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过程优化
✓ 已验证
产品关联
DOI
高影响因子
e-Journal of Surface Science and Nanotechnology
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2012
·
IF 0
L. Z. Pei,Y. Q. Pei,Y. K. Xie,Z. Y. Cai
Calcium sulfate and calcium vanadate nanostructures have been synthesized by a hydrothermal route using calcium sulfate and sodium vanadate as the raw materials. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and photoluminescence (PL) spectrum. XRD and SEM observation show that the products are composed of calcium sulfate nanosheets with orhorhombic CaSO4 phase and calcium vanadate nanorods with tetragonal CaV4O9 phase. The size and morphology of the products can be adjusted by controlling the hydrothermal conditions and raw materials. The size of calcium sulfate nanosheets and calcium vanadate nanorods increases obviously with increasing the hydrothermal temperature and reaction time. The formation process of the calcium sulfate and calcium vanadate nanostructures is also discussed. [DOI: 10.1380/ejssnt.2012.585]
研究领域:
无机化学
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材料科学
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纳米技术
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固体化学
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功能材料
✓ 已验证
DOI
POLYMER COMPOSITES
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2016
·
IF 2.004
Peng Wang,Pengzheng Liu,Fan Xu,Xiaoxia Fan,Huipin Yuan,Hong Li,Yonggang Yan
Ternary biocomposites of dicalcium phosphate (DCP), calcium sulfate (CS), and poly(amino acid) copolymer (PAA) could be used as a promising degradable biomimic bone substitute. Using an in vitro degradation model, we evaluated the influence of polymerization conditions, initial amino acids, and (DCP + CS)/PAA ratio on the degradation of the resulting materials. PAA degradation was affected by both the polymerization conditions and the initial amino acids, and the degradation of the DCP/CS/PAA composites was affected by the (DCP + CS)/PAA ratio. Using a certain initial amino acids (75% ε-aminohexanoic acid, 19% γ-aminobutanoic acid, 4% l -proline, and 2% l -lysine) and polymerization conditions (i.e., 210°C for 2.5 h) as the polymeric phase, (DCP + CS)/PAA biocomposites were prepared with 70%, 60%, and 40% PAA. All of the biocomposites were degradable, which resulted in the release of ions/amino acids and a slight pH fluctuation of 6.76 to 7.20. In addition, these biocomposites were biocompatible based on the proliferation of L929 but varied with the degradation rates. These results suggest the potential to control the degradation rates of (DCP + CS)/PAA biocomposites for bone regeneration. POLYM. COMPOS., 39:E122–E131, 2018. © 2016 Society of Plastics Engineers
研究领域:
生物材料学
·
组织工程学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Huiling Du,Jingwen Wang,Pengchao Xie,Yong Liu
S(IV)-based advanced reduction processes have been viewed as effective strategies to eliminate nitrate (NO 3 − ) from water. In this work, CaSO 3 was introduced as the slow-release source of S(IV), and the combination of UV and CaSO 3 was applied for NO 3 − reduction. 30 mg N/L of NO 3 − could be removed in the UV/CaSO 3 process after 60 min reaction; UV irradiation and hydrated electrons ( e aq − ) reduction were responsible for the NO 3 − removal. The generated nitrite (NO 2 − ) could further be removed in this process (UV/CaSO 3 ). The degradation of NO 3 − increased from 65.8% to 100% with elevating CaSO 3 dosage from 0.2 to 2 g/L, and the accumulation of NO 2 − decreased accordingly. Almost 100% removal of NO 3 − was achieved with initial pH being 3–12 without NO 2 − accumulation after reaction. The effects of anions (Cl − , CO 3 2− , and SO 4 2− ) on the NO 3 − degradation and NO 2 − accumulation in UV/CaSO 3 were negligible. Nitrogen (N 2 ) was demonstrated as the major gaseous product during the NO 3 − reduction, and nitrogen-sulfur compounds (not NO 2 − or NH 4 + ) remained the final liquid reduction products of NO 3 − . This study revealed that UV/CaSO 3 would be a promising approach to remove NO 3 − chemically and simultaneously control the NO 2 − accumulation.
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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Shuaifeng Liu,Edouard Asselin,Zhibao Li
The disposal of titanogypsum, also known as red gypsum, which is generated during the titanium dioxide sulfate process, has become a significant environmental challenge. We propose a new process to recover iron impurities such as FeCl2·4H2O and to convert titanogypsum to saleable hemihydrate gypsum. For this purpose, we use HCl–FeCl2 solution generated via the reaction of H2SO4–FeSO4 with CaCl2 to leach iron hydroxide from titanogypsum. The hemihydrate precipitation and phase-transition kinetics of the reaction of HCl–H2SO4–FeSO4 with CaCl2 are experimentally investigated at 353 K. The common ion effect of CaCl2 in the FeCl2 solution for FeCl2·4H2O crystallization is predicted by NRTL modeling of the solid–liquid equilibria of the FeCl2–CaCl2–H2O system. High-quality, saleable α-gypsum and FeCl2·4H2O solids obtained by treating titanogypsum samples provided by a commercial processing plant further shows that the new process is feasible.
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
CONSTRUCTION AND BUILDING MATERIALS
·
2020
·
IF 4.419
Woo Sung Yum,Jung-Il Suh,Do Hoon Kim,Jae Eun Oh
Recently, the combined use of calcium oxide (CaO) and calcium formate (Ca(HCOO) 2 ) has been proposed as an alternative activator for ground granulated blast furnace slag (GGBFS) (referred to as CaO-Ca(HCOO) 2 -activated GGBFS system). However, this clinker-free binder system produces calcium aluminate hydrate (C 2 AH 8 ), generally leading to the degradation of cementitious binder systems by its conversion to other phases. Thus, in this study, attempts to remove C 2 AH 8 from this system without losing the strength are suggested by the use of two additives (i.e., calcium sulfate (CaSO 4 ) and calcium nitrate (Ca(NO 3 ) 2 ), respectively). Results revealed that the above-mentioned additives completely remove C 2 AH 8 in the initial curing stage via its conversion to ettringite or NO 3 - and NO 2 -AFm, respectively. In addition, the additives reduced the extent of the total shrinkage and the standard deviation of strength results of triplicate samples. However, CaSO 4 exerted a beneficial effect on the strength, while Ca(NO 3 ) 2 exerted a marginal or detrimental effect on the strength. Therefore, this study suggested a new mixture form of an activator, comprising CaO , Ca(HCOO) 2 , and CaSO 4 , to activate GGBFS for maintaining strength without the conversion issue of C 2 AH 8 .
研究领域:
建筑材料学
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材料科学
✓ 已验证
DOI
高影响因子
MOLECULES
·
2021
·Vol. 26
·期 4
·1154
·
IF 4.412
Minjuan Cai,Sen Quan,Jinjun Li,Feng Wu,Gilles Mailhot
Desulfurized gypsum (DG) as a soil modifier imparts it with bulk solid sulfite. The Fe(III)–sulfite process in the liquid phase has shown great potential for the rapid removal of As(III), but the performance and mechanism of this process using DG as a sulfite source in aqueous solution remains unclear. In this work, employing solid CaSO3as a source of SO32−, we have studied the effects of different conditions (e.g., pH, Fe dosage, sulfite dosage) on As(III) oxidation in the Fe(III)–CaSO3system. The results show that 72.1% of As(III) was removed from solution by centrifugal treatment for 60 min at near-neutral pH. Quenching experiments have indicated that oxidation efficiencies of As(III) are due at 67.5% to HO•, 17.5% to SO5•−and 15% to SO4•−. This finding may have promising implications in developing a new cost-effective technology for the treatment of arsenic-containing water using DG.Keywords:desulfurized gypsum;Fe(III);CaSO3;As(III);resource utilization
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
HYDROMETALLURGY
·
2024
·
IF 4.8
Qingfeng Zhou,Xiangdong Ma,Xunhui Xiong
This work proposes the roasting of amblygonite with calcium sulfate followed by water leaching to extract lithium and phosphorus. Various roasting parameters including roasting temperature, the mass ratio CaSO 4 /ore, roasting time as well as leaching parameters, such as the liquid/solid ratio, temperature and time, have been carefully investigated. The lithium extraction efficiency can be as high as 99.8% with a mass ratio of CaSO 4 /ore of 0.85 after roasting at 775 °C for 1 h and water leaching at a liquid/solid ratio of 3 mL/g at 100 °C for 2 h. The XRD analysis demonstrates that the fluoride in the amblygonite can be converted into Ca 5 (PO 4 ) 3 F and CaF 2 . Lithium in the leach liquor can be recovered as Li 2 CO 3 . Meanwhile, the phosphorus in the water leach residue can be recovered as FePO 4 with a high recovery of 96.6% after acid dissolution and precipitation, which can be further treated to produce LiFePO 4 .
研究领域:
矿物加工工程
·
无机化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）