MINERALS ENGINEERING
·
2024
·
IF 4.9
Jiajun Liu,Guofan Zhang,Binbin Li,Xinya Fu,Sen Li
In this study, we aimed to address the problem of fine-grained serpentine forming “slime coating” on the surface of pyrite, which deteriorates the flotation of pyrite, by systematically investigating the effects of HPMA on the separation of pyrite and serpentine, as well as the underlying mechanism. The flotation results indicated that the recovery of pyrite deteriorated by serpentine was significantly increased and reached 90 % by adding 30 mg/L of HPMA at pH 9.00. The total organic carbon (TOC) test and zeta potential test results revealed that the adsorption of HPMA on serpentine was much stronger than that on pyrite. The adsorption behavior was confirmed by X-ray photoelectron spectroscopy (XPS) analyses, which demonstrated that HPMA could chelate with positively charged Mg ions on the surface of serpentine, resulting in a significant change in the surface charge of serpentine to a negative state. The positive effect of HPMA on pyrite flotation was visualized by a scanning electron microscope-energy dispersive spectroscopy (SEM-EDS) analyzer and characterized by the major elemental content. As a result of the addition of HPMA, the surface charge of serpentine was changed from positive to negative, which resulted in the disruption of co-cohesion between serpentine and pyrite. This result enhanced the natural floatability of pyrite and the adsorption of collector potassium amyl xanthate (PAX) on pyrite, thus achieving the selective flotation between pyrite and serpentine.
研究领域:
矿物加工工程
·
环境科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF MINERAL PROCESSING
·
2017
·
IF 1.561
Cheng Zhang,Cheng Liu,Qiming Feng,Yanfei Chen
Utilization of N -carboxymethyl chitosan (N-CMCh) to limit the detrimental effect of serpentine on the flotation of pyrite is presented in this work. Flotation results show that the presence of hydrophilic serpentine slimes results in lower recoveries of the valuable pyrite. Utilization of N -carboxymethyl chitosan can limit the detrimental effect of serpentine on the flotation of pyrite. Zeta potential measurements illustrate that N-CMCh is with negative charge and the electrostatic interaction between serpentine and N-CMCh is occurred at pH 8.5, then the serpentine zeta potential will be changed from positive to negative, the electro-steric attraction converts into electro-steric repulsion between pyrite and serpentine and the pyrite recovery is improved.
研究领域:
矿物加工工程
·
材料化学
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
·
2024
·
IF 4.9
Dezhi Liu,Yangyang Huai,Rui Liao,Binbin Li,Lingming Zeng
During the serpentine-contained sulfide ores flotation process, the presence of serpentine slimes will intensively deteriorate the flotation performance of sulfide ores due to hetero-coagulation. To handle this issue, tetrapotassium pyrophosphate (TKPP) was used as a novel depressant in this work. Micro-flotation results revealed that the addition of 5 g/L fine serpentine particle (−10 µm) caused a substantial reduction of approximately 82.5 % in pyrite recovery at pH 9. However, the detrimental impact of fine serpentine could be efficiently mitigated by the application of 30 mg/L TKPP, with a marked increase in pyrite recovery from 10.15 % to 91.25 %. The underlying mechanisms were elucidated using various characterization methods, revealing a significant shift in the surface charge of serpentine from positive to negative upon the addition of 30 mg/L TKPP, while the surface charge of pyrite remained largely unchanged. Consequently, a well-dispersion state of the mixed minerals pulp was achieved due to the identical surface charge. The alteration mechanisms of TKPP on serpentine involved the selective adsorption through forming P-O-Mg bonds and the accelerated decomposition of Mg 2+ from serpentine. This study highlights the promising role of TKPP in reducing Mg in sulfide concentrator, proving a feasible solution for sulfide beneficiation operations.
研究领域:
矿物加工工程
·
化学工程
✓ 已验证
DOI
高影响因子
Minerals
·
2023
·Vol. 13
·期 3
·318
·
IF 2.5
Yingli Chen,Xiyun Yang,Linglong Wu,Lirong Tong,Jing Zhu
This paper describes a leaching-purifying-precipitation process to recover magnesium from serpentine acid-leaching solution and to synthesize high purity Mg(OH)2and 4MgCO3·Mg(OH)2·4H2O. Fe, Al, and Cr in the leaching solution were removed using the oxidation precipitation method with active MgO as a precipitant and H2O2as an oxidant. Ni, Co and Mn were removed by Na2S precipitation to obtain a pure MgSO4solution. Mg2+ions were first precipitated with NH3·H2O to synthesize Mg(OH)2, followed by NH4HCO3precipitation to obtain 4MgCO3·Mg(OH)2·4H2O. A small part of MgSO4coprecipitates with Mg(OH)2to form MgSO4·5Mg(OH)2·3H2O. The Mg(OH)2was aged with a diluted NaOH solution to remove the sulfur; the two-stage precipitation percentage of Mg is 96.3%. Mg(OH)2has a purity of 98.48% with a sulfur content of 0.28%. This process provides a promising method for the high-efficiency recovery of Mg and the large-scale production of the high purity of Mg(OH)2from the serpentine.Keywords:serpentine;two-stage counter current leaching;remove impurity;MgSO4·5Mg(OH)2·3H2O;high purity Mg(OH)2
研究领域:
冶金工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Guangsheng Zeng,Wei Chen,Sheng Liu,Guangyi Liu
The slime coatings of serpentine via its hydrophobic Si-O layers significantly weaken the floatability of the hydrophobized sulfide minerals. In this paper, sodium lignosulphonate (SLS) was adopted to avoid the aggregation of fine serpentine particles on to the hydrophobized pyrite surface. The micro-flotation findings indicated that for the artificial mixture of pyrite and serpentine (2:1 mass ratio), 1.0 × 10 –4 mol/L sodium isobutyl xanthate (SIBX) only floated out ∼22 % pyrite at pH ∼9.0, while, after extra addition of 70 mg/L SLS, the floatability of pyrite was restored and its recovery reached ∼90 %. In situ AFM (Atomic Force Microscope), contact angle, zeta potential, fourier transform infrared spectrometer (FTIR) and optical microscope deduced that the strong affinity of SIBX to pyrite rendered it replace the most part of the pre-aggregated SLS from pyrite surface, thus to restore the hydrophobicity of pyrite and further decrease the zeta potential. In addition, SLS attached on the positively-charged Mg sites of serpentine through its carboxyl and phenolic hydroxyl groups reduce the hydrophobicity and zeta potential of serpentine. While, the hard base O atom/anion exhibited much stronger affinity to hard acid Mg cation than that of the soft base S atom/anion, SIBX hardly replaced the adsorbed SLS from serpentine surface. Therefore, the increased electrostatic repulsion and weakened hydrophobic attraction between the SLS-adsorbed serpentine and SIBX-hydrophobized pyrite avoided their aggregation. The combination of SLS and SIBX realized the selective flotation separation of pyrite from serpentine.
研究领域:
矿物加工工程
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2022
·
IF 13.4
Xuewei Li,Xu Zhao,Juanjuan Zhang,Jingwei Hao,Qiwu Zhang
Recovery of phosphorus from wastewater through struvite crystallization is one of the most attractive methods. However, the cost of chemical consumption makes this technology is unattractive to some extent. In this work, highly active serpentine was prepared by one-step mechanical activation and then used to recover phosphate as struvite from the black water containing 132.8 mg/L phosphorus and 3144 mg/L ammonia nitrogen. The results indicated that the prepared active serpentine can release magnesium ions and hydroxide ions simultaneously into an aqueous solution and is an ideal raw material for struvite crystallization. The factors for phosphorus recovery in this process mainly include mechanical activation intensity, serpentine dosage, and contact time. For the actual black water, a high recovery rate of phosphorus (>98%) is achieved by using active serpentine as the magnesium and alkali source for struvite precipitation. The recovery product was identified as struvite with a median particle size of 32.96 μm. It was confirmed that the mechanical activation damaged the crystal structure of the raw serpentine, improving the activity of Mg 2+ and OH − . The undissolved Si-containing particles act as crystal seeds, accelerating the struvite crystallization process. Furthermore, a pilot-scale test was conducted with a rural public toilet in Xiong'an New District, Hebei Province. The results showed that an acceptable phosphorus recovery (98%) could be achieved using active serpentine. Additionally, it was demonstrated that the serpentine process to recover phosphate as struvite reduced the cost by 54.4% in compared with an ordinary chemical process. The active serpentine is a promising dual source of magnesium and alkali for the phosphorus recovery by the struvite method. It has a potential prospect for the large-scale application in phosphorus recovery and struvite fertilizer production.
研究领域:
环境科学
·
废水处理
·
资源回收
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Cleaner Production
·
2024
·
IF 9.7
Liming Tao,Guoyuan Xiang,Zekun Miao,Jianjun Wang,Wangni Wu,Mengjie Tian,Wenkai Jia,Zhiyong Gao
In industry, the content of P 2 O 5 , mainly derived from apatite , must not exceed 0.5% in spodumene concentrate. Strong acid leaching of phosphorus-containing minerals with the disadvantages of seriously harming the environment and high investment in equipment, is the main method for removing phosphorus. Therefore, in this work, sodium alginate (SA) depressant was effectively used to depress spodumene and float apatite . Li 2 O grade and recovery in the spodumene concentrate were 6.18% and 87.66% obtained by the binary mixed mineral flotation tests with 1.1 × 10 −4 mol/L SA and 3 × 10 −4 mol/L sodium oleate (NaOL) collector at pH 5. The P 2 O 5 content in the real spodumene concentrate could be reduced from 4.58% to 0.49% using 500 g/t of SA. The contact angle tests showed that the hydrophilicity of spodumene increased after the treatment of SA. Zeta potential and atomic force microscope (AFM) measurements revealed that anionic SA had more adsorption on the spodumene surface and hindered the subsequent adsorption of NaOL. Density functional theory (DFT) calculations further showed that SA could chelate with Cu 2+ pre-adsorbed on the spodumene surface to form a 4-membered ring. Therefore, the method of reverse flotation has great application potential in the dephosphorization of high-phosphorus lithium concentrate.
研究领域:
矿物加工工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2015
·
IF 2.515
Xiaoli Sun,Xiguang Liu,Bujun Yang,Lianchi Xu,Shaoming Yu
Chrysotile nanotubes (ChNTs) synthesized under hydrothermal conditions were functionalized by surface grafting in toluene with 3-mercaptopropyltrimethoxysilane (MPTMS). The mercapto functionalized ChNTs (ChNTs-SH) were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N 2 adsorption–desorption. The adsorption of Pb(II) and Cd(II) on ChNTs-SH was investigated systematically by evaluating the effects of contact time, adsorbent dosage, initial pH and temperature. Initial pH could play an important role on the adsorption of Pb(II) and Cd(II) onto ChNTs-SH. The adsorption kinetics and isotherms of Pb(II) and Cd(II) on ChNTs-SH indicated that the kinetic data of adsorption reactions were well described by the pseudo-second-order model (R 2 = 0.9960 and 0.9970, respectively) and the adsorption isotherms were fitted well by the Langmuir model ( q m Pb(II) = 83.96 mg/g, q m Cd(II) = 39.23 mg/g at 298 ± 1 K). The thermodynamic parameters (Δ G , Δ H and Δ S ) indicated that the adsorption process of Pb(II) and Cd(II) on ChNTs-SH was spontaneous and endothermic. ChNTs-SH could obviously improve the adsorption capacity for Pb(II) by 225.4% and for Cd(II) by 123.5% as compared with ChNTs. Overall, ChNTs-SH could provide a potential remedy for heavy metal contamination in wastewater.
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
Polymers
·
2022
·Vol. 14
·期 23
·5255
·
IF 4.967
Xiaohong Yi,Jingshu Huang,Yizhang Tong,Hui Zhao,Xianwu Cao,Wei Wu
Biodegradable polylactide (PLA) has been widely utilized in people’s daily lives. In order to improve the fire safety of PLA, ammonium polyphosphate (APP) was self-assembled onto the surface of serpentine Ni3Si2O5(OH)4through the electrostatic method, followed by mixing with PLA by melt compounding. The APP-modified serpentine (serpentine@APP) dispersed uniformly in the PLA matrix. Compared with pure PLA, the PLA composite with 2 wt% serpentine@APP reduced the peak heat release rate (pHRR) and total heat release (THR) by 43.9% and 16.3%, respectively. The combination of APP and serpentine exhibited suitable synergistic flame-retardant effects on the fire safety enhancement of PLA. In addition, the dynamical rheological tests revealed that the presence of APP and serpentine could reduce the viscosity of PLA composites. The plasticizing effects of APP and serpentine benefited the processing of PLA. The mechanical properties of PLA/serpentine@APP maintained suitable performance as pure PLA. This study provided a feasible way to enhance the fire safety of PLA without sacrificing its mechanical properties.
研究领域:
材料科学
·
消防安全
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Guangsheng Zeng,Wei Chen,Sheng Liu,Guangyi Liu
Hypothesis: In xanthate flotation system, the aggregation of serpentine on sulfide minerals significantly weakened their floatability. And it was generally assumed that the electrostatic attraction was of the dominant driver for coating of serpentine slimes. In this paper, the hydrophobic interaction between the “talc-like” cleavage plane of serpentine and the xanthate-hydrophobized surface of sulfide minerals was proposed as the dominated driver. Experiments: To evaluate the aggregation of serpentine on pyrite surface, a novel experimental protocol was designed, and the aggregation behavior and mechanism in the absence and presence of sodium isobutyl xanthate (SIBX) were explored through in situ optical microscope, micro-flotation, contact angle, zeta potential and FT-IR. Afterwards, the disaggregation mechanism of 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) to the aggregates of serpentine on pyrite surface was revealed. Findings: The electrostatic attraction facilitated the slight aggregation of serpentine slimes on bare pyrite surface. The hydrophobic interaction between the “talc-like” plane of serpentine and SIBX-covered pyrite significantly promoted the aggregation between them, which remarkably weakened the floatability of pyrite. The attendance of HEDP anions reversed the surface potential of the octahedral Mg-O layers of serpentine from the positive into the negative, thus to prevent the aggregation of the HEDP-anchored serpentine with the SIBX-covered pyrite via the strong electrostatic repulsion between them. As a result, the disaggregation as well as SIBX flotation separation of pyrite from serpentine was realized. This investigation also provided new insights into the aggregation and disaggregation between serpentine and sulfide minerals during froth flotation.
研究领域:
矿物加工工程
·
表面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Bionic Engineering
·
2024
·Vol. 21
·期 2
·913-923
·
IF 4.9
Liu Xingyu,Chen Junxu,Wang Rui,Su Yifan,Zhou Zhangheng,Hou Zezhong,Li Zhuoran,Zhao Junhao,Shi Weicai,Yu Xinquan,Yu Zhaopeng,Zhang Youfa
The produced water from the oilfield was purified with filter material and then injected back into the ground. The serpentine filter material was easy to harden with the increase in filtration amount, which affected the water quality. A superhydrophilic/underwater oleophobic serpentine filter material was successfully prepared by a simple method of coating modification, which exhibited long-lasting filtration of oily water, good filtration and anti-fouling properties, and resistance to harden. The film-forming material of the superhydrophilic/underwater oleophobic coating was composed of SiO 2 particles with small size, which could completely and evenly cover the filter particle. The weight loss was only 7.6% after mechanical stirring for 90 min. Compared with the original filter material, the superhydrophilic/underwater oleophobic serpentine filter material showed a better anti-fouling ability and resistance to harden. The filtration of crude oil emulsion and oil slick sewage showed a better backwashing performance. After 35 cycles of continuous filtration of suspended solids in wastewater, the backwashing rate reached 78.4%. The results provided an effective method for the filtration of oily wastewater in the oilfield.
研究领域:
环境工程
·
材料科学
·
化学工程
·
石油工程
·
水处理技术
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Qian Peng,Ying Dai,Kun Liu,Xuekun Tang,Muyang Zhou,Yingjie Zhang,Jiajie Xing
A metal-free peroxymonosulfate catalyst based on chrysotile and graphite carbon nitride (g-C 3 N 4 ) was synthesized for the first time. The abundant hydroxyl groups of chrysotile can react with amine groups of urea-derived intermediates and accelerate formation of double nitrogen defects (N-vacancy and cyano group) in g-C 3 N 4 , which can drastically improve the activation efficiency of PMS. The introdution of chrysotile can greatly increase the reaction time of hydroxyl and amine groups, and promote the generation of double nitrogen defects. This catalyst displayed superior catalytic performance for rhodamine B (RhB) degradation than bare chrysotile and g-C 3 N 4 . Moverover, this catalyst also has good cycle performance, structural stability and universal applicability, which provides an idea for the comprehensive utilization of asbestos tailings and environmental remediation.
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
危险品化学品经营许可证（带存储）