Minerals
·
2022
·Vol. 12
·期 8
·996
·
IF 2.818
Yupeng Qian,Xuan Qiu,Tiewei Shen,Yangyang Huai,Bin Chen,Zhen Wang
In the flotation of semi-soluble minerals such as calcite and fluorite, Ca2+is one of the common dissolved components influencing the collector adsorption behaviors on the mineral surfaces. However, there is very limited research focusing on how the dissolved Ca2+affects the separation of fluorite and calcite. In the study, with sodium oleate (NaOL) as a collector and tannic acid (TA) as a depressant, a flotation test, zeta potential measurement, and adsorption experiment in the presence of Ca2+were conducted. Flotation tests indicated that in the presence of Ca2+, fluorite and calcite were both significantly depressed by TA, leading to difficulty in the separation of the two minerals. It was also found that the depression effect on fluorite flotation was minimized with a high concentration of NaOL. Zeta potential measurement and the adsorption experiment results are consistent with the flotation results, revealing that it is only in the low concentration of NaOL that the flotation of fluorite was depressed by TA in the presence of Ca2+. Specifically, in the low concentration of NaOL, TA adsorbed on the fluorite surface and depressed the flotation of fluorite due to the preferential interaction between NaOL and Ca2+in the solution leading to a shortage in the effective NaOL in the solution. In the high concentration of NaOL, the adsorbed TA on the fluorite surface was displaced by the excessive NaOL in the solution; hence, the flotation of fluorite was recovered. In contrast, TA always hinders the interaction of NaOL with calcite regardless of the presence and absence of Ca2+and NaOL, hence, depressing the flotation of calcite. The study presented that a high concentration of NaOL may mitigate the negative effect of Ca2+on the fluorite surface and improve the separation of fluorite from calcite.Keywords:calcium ion;fluorite;adsorption mechanism;tannic acid
研究领域:
矿物学
·
浮选化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOID AND POLYMER SCIENCE
·
2025
·
IF 2.3
Tumrani Sadam Hussain,Sharma Bharat Prasad,Otho Ali Raza,Ayob Eman A.,Amin Mohammed A.,Soliman Mohamed Mohamed,Soomro Razium Ali,Karakuş Selcan
The environmental impact of biodegradable microplastics (BMPs) is profoundly influenced by aging-induced surface transformations, yet their interactions with persistent organic pollutants, such as perfluorooctanoic acid (PFOA), remain poorly understood. This work investigates how aging polylactic acid (PLA), a common BMP, in simulated surface water for 80 days alters its physicochemical properties and behavior towards PFOA. Aging triggered oxidative and hydrolytic degradation, leading to pronounced morphological changes, including increased surface roughness, hydrophilicity, and oxygen-to-carbon (O/C) ratio from 0.82 to 1.28. These transformations introduced hydroxyl and carboxyl functional groups, shifting the PFOA adsorption mechanism from physisorption (in fresh PLA) to chemisorption (in aged PLA) via stronger electrostatic interactions and hydrogen bonding. Additionally, kinetic and isotherm analyses revealed a tenfold increase in PFOA monolayer adsorption capacity for aged PLA (PLA-80) compared to pristine PLA. Density functional theory (DFT) calculations corroborated these findings, demonstrating a reduced HOMO–LUMO energy gap upon PFOA adsorption, indicative of enhanced electronic reactivity and charge transfer. Topological analysis further identified multiple hydrogen-bonding sites, confirming the dominance of electrostatic forces in pollutant retention. These results underscore the critical role of aging in amplifying BMPs’ environmental reactivity, emphasizing the urgent need to incorporate aging processes into risk assessments for biodegradable plastics.
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
Silicon
·
2019
·Vol. 12
·期 2
·327-338
·
IF 1.21
Wei Mengnan,Ban Boyuan,Li Jingwei,Sun Jifei,Li Feifei,Jiang Xuesong,Chen Jian
A novel green cationic surfactant Poly (propylene glycol) bis (2-aminopropyl ether) (PEA) with multiple amine groups was utilized as a collector for flotation separation of quartz from feldspar-quartz associated ore (FQA) without acid (particularly, HF) and alkali. The collecting performances and the adsorption mechanisms of PEA on the quartz/FQA were investigated through flotation experiments, ICP-OES, XRD, Zeta potential, FTIR and XPS measurements. A remarkable separation of the quartz from FQA has been realized in an environmental friendly way. The froth flotation results show that the flotation recovery of quartz is 97.79% and that of FQA is 19.30% at pH 9.00–9.50 with 10 −4 M PEA when the particle size ranges from 150 to 270 μm. The results of batch flotation, ICP-OES and XRD analyses show that the first flotation product is almost quartz, while more feldspar and little quartz exist in the sink product when compared with the FQA feed. The mechanism of PEA acting as the collector for the separation of quartz/feldspar has been investigated. The PEA is adsorbed on the quartz surface by electrostatic and hydrogen bonding interaction with ─NH 3 + /─NH 2 head groups, while is less adsorbed on the feldspar surface due to electrostatic repulsion between the K + / Na + ions and the positively charged ─NH 3 + /─NH 2 head groups of PEA. A conceptual adsorption model of the PEA cationic collector on the quartz and the FQA surfaces has been proposed.
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
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2020
·Vol. 28
·期 1
·1052-1060
·
IF 3.056
Sun Xu,Xu Li,Jiang Weina,Xuan Yan,Lu Wen,Li Zhong,Yang Shilong,Gu Zhenzhen
In the present study, a magnetic adsorbent, rhein-coated magnetic Fe 3 O 4 nanoparticle (RMNP), for Pb 2+ and Mg 2+ had been developed, and adsorption mechanism was studied via low-field NMR. RMNP was characterized by TEM, FTIR, and XRD. RMNP could adsorb and remove Pb 2+ and Mg 2+ from water and was successfully applied to remove Pb 2+ and Mg 2+ from wastewater, with satisfactory recovery rates and high adsorption capacities. The calculated maximum adsorption capacity for Mg 2+ and Pb 2+ was approximately 69.3 and 64.9 mg g −1 of RMNP, respectively, which was better than some results reported. Low-field NMR results showed that Pb 2+ or Mg 2+ enhanced the T 2 relaxation time of RMNP, which suggested that RMNP selectively coordinated with Pb 2+ or Mg 2+ and led to the aggregation of RMNP, furthermore removal of Pb 2+ or Mg 2+ from water. The standard curves for △T 2 -cation concentration exhibited good line correlation. The linear ranges were from 4.2 × 10 −6 to 2.0 × 10 −4 mol L −1 for Pb 2+ and from 5.0 × 10 −6 mol L −1 to 1.0 × 10 −4 mol L −1 for Mg 2+ , respectively. The limits of detection were 1.4 × 10 −6 mol L −1 for Pb 2+ and 2.1 × 10 −6 mol L −1 for Mg 2+ , respectively. In short, low-field NMR could clearly display the interaction between RMNP and Pb 2+ or Mg 2+ , even be used to detect Pb 2+ or Mg 2+ in suitable condition. Besides, this method could be expanded to study the interaction between other magnetic adsorbents and analytes.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Ge Zhang,Huifen Yang,Tong Zhao,Xuan Li,Yichen Zhou,Song Guo
The thermal adsorption residue (TDR) from oil sludge co-contaminated soil was employed to remove As(III), Zn(II), Cu(II), Cd(II) in aqueous solution. The results showed that the TDR could efficiently neutralize the acid and adapt to the extensive pH. The adsorption of four heavy metals on TDR could be divided into three stages. The maximum adsorption capacity were 86.59, 249.07, 339.88, 322.86 mg·g −1 for As(III), Zn(II), Cu(II), Cd(II), respectively. The coexistence of Zn(II)/Cu(II)/Cd(II) could promote As(III) removal but As(III) led to decreasing of Zn(II)/Cu(II)/Cd(II) adsorption capacity in binary system. There was a significant competitive adsorption on TDR among the three cations which followed the selectivity sequence of Cu(II)>Zn(II)>Cd(II). The SEM-EDS, XRD, FTIR and XPS analyses demonstrated that the As(III) was removed via formation of Ca-As precipitation, and the Zn(II), Cu(II), Cd(II) were removed through precipitating as hydroxides/carbonates/silicates combining with ion exchange. Specially, the Cu(II) mainly precipitated in the form of Cu 4 (SO 4 )(OH) 6 ⋅2H 2 O and Cu 4 (OH) 6 SO 4 under sulfuric acid solution environment. Overall, this study indicates the potential of TDR as a cost-effective adsorbent in acid heavy metals contaminated wastewater treatment .
研究领域:
环境科学
·
土壤修复
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Xinyu Zhang,Liuyi Ren,Shenxu Bao,Yimin Zhang
Various studies have shown that the presence of metal ions in the slurry can significantly impact flotation . However, it was still uncertain how iron, a typical metal ion, affected rutile flotation. Micro-flotation experiments, x-ray photoelectron spectroscopy , icp-oes, solution chemistry calculation, zeta potential and contact angle test were used to explore the effect of iron ions on the surface properties and floatability of rutile in this investigation. Micro-flotation results showed that iron ions not only substantially increased the rutile flotation recovery from 42.27 % to 75.69 % at pH = 4, but also converted the optimal pH of flotation from a point (pH = 4) to a platform (pH = 4–8). Solution chemistry calculations indicated that iron ions could form complexes with hydroxyl to produce FeOH 2+ , which reacted with benzohydroxamic acid (BHA) to create [Fe(C 7 H 6 NO 2 ) 2 ] + at pH=4–7. The analysis conducted through X-ray photoelectron spectroscopy , coupled with the results obtained from contact angle measurements, revealed that the complex [Fe(C 7 H 6 NO 2 ) 2 ] + had the capability to engage with Ti-OH groups, improving the hydrophobicity of rutile surface. Zeta potential analysis results further illustrated that Fe 3+ /BHA complexes reinforce the adsorption of BHA and iron ions onto rutile surface by the formation of [Fe(C 7 H 6 NO 2 ) 2 ] + . In addition, the O1s peak fitting results and ICP-OES analysis results proved that at the same pH, 60 mg/L was the optimal concentration for iron ion activation, which may be limited by Saturated adsorption capacity of [Fe(C 7 H 6 NO 2 ) 2 ] + .
研究领域:
矿物加工工程
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2024
·
IF 6.9
Qing Shao,Yiyi Yi,Yuxiang Xie,Haike Yang,Jingyi Guo,Zizheng Liu,Yiqun Chen,Jun Wan
The utilization of steel slag as an adsorbent for wastewater treatment (e.g., phosphorus removal) is a promising direction for the simultaneous disposal of solid waste and eutrophication control. In this study, 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) was selected as a representative phosphonate and its adsorption performance and mechanism on steel slag were explored. The experiment results show that for the HEDP solution with a concentration of 0–50 mg/L, the removal efficiency of steel slag was 85–88% and the adsorption capacity was 0.0835–8.2793 mg-P/g. The HEDP adsorption behavior on steel slag conformed to the pseudo-second-order adsorption kinetics model. Both the Freundlich and Langmuir adsorption isotherm models can describe the experimental data well. And the theoretical maximum adsorption capacity at 25°C was calculated as 23.74 mg-P/g. Combined with our SEM, XRD, FTIR, and XPS analyses, the adsorption mechanism involved ligand exchange, hydrogen bond interaction, and electrostatic attraction. After 5 reuse cycles, the regeneration efficiency of steel slag remained 77% by using 1 mol/L NaOH. The research work in this paper proves that steel slag, as a solid waste with large emissions in China, can effectively remove HEDP, which supplies a new way for the resource utilization of steel slag.
研究领域:
环境科学
·
废水处理
✓ 已验证
产品关联
DOI
高影响因子
Sustainability
·
2018
·Vol. 10
·期 11
·4250
·
IF 2.075
Shuang Xu,Weiguang Yu,Sen Liu,Congying Xu,Jihui Li,Yucang Zhang
A low-cost biochar was prepared through slow pyrolysis of banana pseudostem biowaste at different temperatures, and characterized by surface area and porosity analysis, scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). It was shown that the biochar prepared at low pyrolysis temperature was rich in oxygen-containing groups on the surface. Adsorption experiments revealed that the biochar prepared at 300 °C (BB300) was the best adsorbent for Cr(VI) with 125.44 mg/g maximum adsorption capacity at pH 2 and 25 °C. All the adsorption processes were well described by pseudo-second-order and Langmuir models, indicating a monolayer chemiadsorption. Furthermore, it was demonstrated that adsorption of Cr(VI) was mainly attributed to reduction of Cr(VI) to Cr(III) followed by ion exchange and complexation with the biochar.Keywords:biochar;banana pseudostem;chromium;adsorption mechanism
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
WASTE MANAGEMENT
·
2020
·
IF 5.448
Jingwei Li,Yinhe Lin,Jian Shi,Boyuan Ban,Jifei Sun,Yong Ma,Fanmao Wang,Wei Lv,Jian Chen
Separation and recovery of high-purity Si powder from kerf-loss Si slurry waste is a critical challenge for the photovoltaic industry. A green surfactant poly (propylene glycol) bis (2-aminopropyl ether) (PEA) was employed as a collector to facilitate the separation of Si and SiC from kerf-loss Si waste during flotation process. Single flotation tests of Si and SiC were conducted using 5 × 10 −6 mol/L PEA, respectively. The separation efficiencies of Si and SiC in conjunction with PEA adsorption mechanism were investigated. It was found that the maximum recoveries rate of SiC and Si were 90.59% (pH 9.00) and 80.93% (pH 1.96), respectively. Furthermore, the maximum Si grade was determined as 92.31% at pH 8.95 for the sinking part of the mixture generating excellent floatability and selectivity. Zeta potential measurements, FT-IR spectra, and XPS analyses demonstrated that PEA was present on the surface of Si and SiC through electrostatic and hydrogen-bond interactions. The adsorption mechanism was explained based on the results. This research provides an efficient and environmentally friendly route for the separation and recovery of high purity silicon from kerf-loss Si waste.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
PubMed
高影响因子
PLoS One
·
2023
·Vol. 18
·期 8
·e0290714
·
IF 3.7
Xiaomei Wu,Meifeng Ye,Jinglong Wang,Feilong Wu,Cenwei Liu,Zhangting Li,Daiyan Lin,Rilong Yang
The utilization of biogas slurry is critical for the sustainable development of animal husbandry. Biomass carbon adsorption is a feasible method for the recycling of nutrients from biogas slurry. However, research on the co-adsorption of ammonia nitrogen and phosphate is scarce. Herein, soybean straw was utilized as the raw material to prepare Ca 2+ -modified biochar (CaSSB), which was investigated for its ammonia nitrogen and phosphate adsorption mechanisms. Compared with natural biochar (SSB), CaSSB possesses a high H/C ratio, larger surface area, high porosity and various functional groups. Ca 2+ -modified soybean straw biochar exhibited excellent adsorption performance for NH 4 + –N (103.18 mg/g) and PO 4 3− −P (9.75 mg/g) at pH = 6, using an adsorbent dosage of 2 g/L. The experimental adsorption data of ammonia nitrogen by CaSSB corresponded to pseudo-second-order kinetics and the Langmuir isotherm model, suggesting that the adsorption process was homogeneous and that electrostatic attraction might be the primary adsorption mechanism. Meanwhile, the adsorption of phosphate conformed to pseudo-second-order kinetics and the Langmuir–Freundlich model, whose mechanism might be attributed to ligand exchange and chemical precipitation. These results reveal the potential of CaSSBs as a cost-effective, efficient adsorbent for the recovery of ammonium and phosphate from biogas slurry.
研究领域:
环境科学
·
农业科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Environmental Technology & Innovation
·
2024
·
IF 6.7
Shuai Shao,Ming Zhang,Zhanao Lv,Yingke Sun,Penghui Li,Runjuan Zhou
Biochar is considered an environmentally friendly and cost-effective option for removing antibiotics from aqueous solutions. In this study, biochar derived from rice straw (RBC) was sequentially modified by KMnO 4 and NaOH (Mn/Na-RBC) to achieve ciprofloxacin (CIP) removal. To explore the adsorption mechanisms between Mn/Na-RBC and CIP, the characterization analyses, adsorption isotherms, thermodynamics, and kinetics were investigated. The results revealed that Mn/Na-RBC significantly increased the specific surface area (154.12 m 2 ·g –1 ), carbonization, and the number of oxygen-containing functional groups compared with pristine biochar, thereby substantially enhancing the CIP adsorption capacity. Through fitting of the adsorption model, it was found that the highest adsorption capacity was 32.25 mg·g –1 under acidic conditions (pH=3), and the pseudo-second-order and Freundlich model fit the adsorption behavior well. The main mechanisms of the adsorption process were pore filling, electrostatic interaction, H-bonding, π–π conjugation, n–π interaction and surface complexation. Moreover, the Mn/Na-RBC still exhibited a remarkable capacity to selectively adsorb CIP even in the presence of high ionic strengths. Thus, Mn/Na-RBC is a promising adsorbent for removing emerging contaminants from aquatic environments.
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
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Jingbo Wang,Xinyue Li,Yushan Lan,Hanyu Wang,Xiulan Ma,Hongbin Wang,Haoyu Xu,Huiqing Liu
The recontamination of farming wastewater with antibiotics and metal ions has emerged as a considerable concern in recent years. In this study, fly ash (FA) served as the adsorbent material, and its modified form (AFA) was developed via response surface optimization. The study involved an analysis of the structure and chemical composition of the fly ash before and after modification, both pre- and post-modification, through the use of scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) analyses. These analyses were aimed at exploring the adsorption mechanism of ciprofloxacin (CIP) in the presence of copper ion (Cu 2+ ) in livestock and poultry wastewater. The study indicates that the optimal modification parameters for AFA include an alkali-to-ash ratio of 1.5, a calcination temperature of 400 °C, and a 3-hour calcination period. At pH 6, AFA exhibited a markedly superior adsorption capacity for CIP in comparison to FA, with AFA achieving 19.32 mg/g and FA only 9.61 mg/g. The adsorption process conforms to the quasi-second-order kinetic model and Langmuir isothermal model.The adsorption capacity for CIP increases at low concentrations, specifically when Cu 2+ levels are below 100 mg/L. Nevertheless, elevated CIP concentrations impede the adsorption process. The adsorption of AFA for CIP is observed to decrease with rising temperature, in contrast to the adsorption of Cu 2+ , which increases as the temperature rises. The adsorption mechanism of AFA is primarily comprised of pore filling, ion exchange, electrostatic interaction, π bond coordination, complexation, and other similar processes.
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
危险品化学品经营许可证（带存储）