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
Journal of Sustainable Metallurgy
·
2024
·Vol. 10
·期 4
·2630-2645
·
IF 2.5
Wu Zi-wang,Wang Lai-xin,Li Jing-wei,Lin Yin-he,Wang Da-long,Zhang Lin,Fan Yu-hang,Tang Wen-ming,Chen Hong-sheng
Vanadium titanomagnetite (VTM) is a complex polymetallic symbiotic mineral dominated by iron, titanium, and vanadium. Iron extraction from VTM is an issue for the utilization of Vanadium titanomagnetite concentrate. In this work, flotation method combined with magnetic sorting was proposed to separate and recover the iron resources from VTM. The reverse cationic flotation of iron ore in VTM was carried out with polyetheramine (PEA, molecular weight of 2000) as collector, and the differences of iron grade and recovery in VTM with different particle sizes were studied. The magnetic separation result shows that the iron grade of the magnetic part is 28.38% with the particle size 100–74 μm, which is 10% higher than the iron grade of the raw ore. The flotation results of magnetic separation products show that PEA-2000 can effectively separate and recover iron from VTM. The iron grade of the magnetic part is increased to 47.27% after flotation process at particle size 100–74 μm, pulp pH 4, PEA-2000 concentration 1 × 10 −4 mol/L, and pulp concentration 10 g/L. The mechanism of flotation separation of Fe from VTM by PEA-2000 was analyzed by zeta potential test, FT-IR test, and XPS test. PEA is adsorbed on the surface of silicate in VTM by electrostatic adsorption and hydrogen bond adsorption, and the iron phase minerals are mutually repulsive, which realizes the separation of iron. The model of iron separation by flotation of PEA-2000 was established. Graphical
研究领域:
矿物加工工程
·
材料科学与工程
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Bingke Tian,Chaofeng Huang,Yingshuang Zhang,Cong li,Hongru Jiang,Chongqing Wang,Hui Wang,Shangbo Zhang,Liuchuang Zhao
Plastics are extensively used in packaging, automobiles, sanitation, agriculture, and architecture due to their lightweight, malleability, corrosion resistance, and low cost. However, their short lifespan leads to the rapid accumulation of plastic waste. Therefore, recycling waste plastics is crucial to conserve resources and protect the environment from "white pollution." This study developed a flotation process to facilitate the recycling of common polyesters by separating polyamide (PA), polycarbonate (PC), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), and polyurethane (PU). The flotation process was based on a hydrophilic gradient induced by modification with methanol, ethanol, and ethanolamine. The floatability sequence of the polyesters was PA < PU < PET < PC < < PMMA in the methanol-based system, PA < PU < PET < < PC ≈ PMMA in the ethanol-based system, and PET < PU < PA < < PC < PMMA in the ethanolamine-based system. The floatability of the polyesters was closely related to the reactivity of ester exchange. Based on the hydrophilic gradients, a cascaded flotation process was designed, following the ester exchange mechanism, to sequentially recover PET, PA, PC, and PMMA. PA, PET, and PU were the sinking plastics after modification with methanol, ethanol, and ethanolamine, respectively, while only PC remained hydrophilic after methanol modification. The purity of PA, PC, PET, and PMMA was 95.10 %, 93.68 %, 89.39 %, and 86.42 %, respectively, with recovery rates of 82.96 %, 83.90 %, 96.08 %, and 100 %. This study presents a promising approach for the flotation separation of waste polyesters.
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 NANOPARTICLE RESEARCH
·
2017
·Vol. 19
·期 2
·1-13
·
IF 2.02
Hu Nan,Liu Wei,Ding Linlin,Wu Zhaoliang,Yin Hao,Huang Di,Li Hongzhen,Jin Lixue,Zheng Huijie
Dye pollution has been a severe problem faced by worldwide environmentalists. The use of nanoparticles as adsorbents has attracted widespread interests for effectively removing dyes, while the separation of them from an aqueous solution is a difficult and important subject. For achieving the simultaneous removal of methylene blue (MB) and nanoadsorbents, this work utilized a commercial hydrophobic silica nanoparticle (SNP) (200.0 ± 10.0 nm in average particle size) as a collector and then developed a novel froth flotation technology without using any surfactants. Under the suitable conditions of anhydrous ethanol dosage of 8 mL, pH of 9.0, SNP concentration of 600 mg/L, and flotation column height of 600 mm, the removal efficiencies of MB and SNPs and the volume ratio reached 91.1 ± 4.6%, 93.9 ± 4.7%, and 10.5 ± 0.5, respectively. Subsequently, the recovered MB-adsorbed SNPs in the foamate were separated by free setting due to their high concentration and massive agglomeration. After free setting, MB could be effectively separated from the recovered MB-adsorbed SNPs by using ethanol at pH 2.0 and repeating five cycles of washing-centrifugation. Additionally, the regenerated SNPs could be reused for removing MB up to five times. Overall, this work had a significant meaning for the treatment of dye-contaminated wastewaters.
研究领域:
环境科学
·
纳米技术
·
水污染控制
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2020
·
IF 7.246
Nan Hu,Keke Zhang,Yana Zhao,Zhijun Zhang,Huizhen Li
Hazardous synthetic dyes have emerged as an imperative issue of water contamination . This investigation focused on the development of a green flotation-based dye removal (FBDR) system to remove trace crystal violet (CV). A natural protein derived from sweet potato waste which was a readily available and low-cost agro-industrial residual was utilized as the collector and frother , due to its biodegradability and nontoxicity. In the first-stage of FBDR, an inclined foam channel with hydrophobic surface was employed to continuously recover sweet potato protein (SPP). Its recovery percentage and volume ratio reached 84.7 ± 4.2% and 7.2 ± 0.4, respectively. Enriched SPP (10.4 ± 0.5 g/L) was then collected by isoelectric precipitation and freeze drying. Encouragingly, SPP induced the desirable foaming and stable bubbles of the solution. Analytical tests, including SEM , FTIR, UV–vis spectra, and fluorescence measurements, confirmed that the SPP-CV complex was formed mainly through the hydrophobic force . In the second-stage, an excellent CV removal was generated with the collection of SPP. The removal efficiency and enrichment ratio of CV were 95.8 ± 4.5% and 9.2 ± 0.4, respectively. The kinetic study indicated that the removal rate markedly increased with increasing air flowrate . In conclusion, this investigation demonstrated the waste protein could be an effective, inexpensive and eco-friendly alternative for classical collector and/or frother, and provided new insights into the disposal of dye wastewaters.
研究领域:
环境科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yijin Feng,Xing Liu,Yingshuang Zhang,Zhiyi Wang,Jiming Su,Ziyue Li,Jianchao Wang,Qianqian Xu,Min Wang,Hui Wang,Hongru Jiang,Chongqing Wang
The growing threat of marine microplastics (MPs) demands effective remediation strategies. This study proposed microbubble flotation (MBF) as a promising solution, utilizing the microbubbles with small size and high stability to enhance the capture efficiency of marine MPs. However, the application of MBF is constrained by the limited comprehension of the interfacial interactions among MPs, microbubbles, and marine cations or microbes. Traditional froth flotation for algae-incubated MPs resulted in removal efficiencies of 0.07% (2–2.5 mm) and 22.39% (48–72 μm), while that of MBF achieved 95.26% and 63.82%, respectively. This decrease in removal efficiencies after algae incubation was caused by the enhanced hydrophilicity of MPs. After 28 days of incubation with algae, the contact angle of MPs decreased from 97.88° to 21.62°, and C=O and O–C=O functional groups were formed while C–O group increased from 2.39% to 10.84%. Although algae-secreted extracellular polymeric substances (EPS) adhered to MPs surface and formed hydrophilic membranes, weakening the hydrophobic interaction between MPs and microbubbles, cations and soluble EPS promoted removal efficiency by reducing microbubble size and enhancing microbubble stability. The positive effects of cations on MPs flotation followed the order: Mg 2+ > Na + > K + > Ca 2+ . Moreover, molecular dynamics simulations further confirmed that fucose-containing sulfated polysaccharide molecules intertwined and sealed the gas–liquid interface via hydrogen bonds, thereby enhancing bubble stability and reducing the radius from 25 Å to 16 Å. These findings offer valuable insights into the environmental interfacial interactions during MPs flotation in marine environments, laying the groundwork for the application of MBF in marine MPs remediation.
研究领域:
环境科学
·
海洋学
·
材料科学
✓ 已验证
产品关联
DOI
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
CHEMOSPHERE
·
2022
·
IF 8.943
Yonglei Wang,Jie Xue,Wentao Sun,Wenjuan Chen,Baosen Liu,Li Jin,Jianing Li,Jingjing Li,Liping Tian,Xiaobo Wang
The effective control of eutrophication caused by algae blooms is still the focus of global attention. The traditional dissolved air floatation process for algae removal has a low adhesion efficiency between bubbles and algal cells and a low removal efficiency of organic pollutants. Aiming to address these defects, this study set up an ozone microbubble-enhanced air flotation experiment to explore the removal trends of algal cells and algal organic matter (AOM) pollution. In contrast to traditional air flotation, this approach targets the removal of various forms of AOM after algal cell damage. The highest removal rates of algal cells, extracellular microcystin (Mc), intracellular Mc-lr and total Mc-lr were 96.6%, 60.1%, 95.2% and 93.7%, respectively. Compared with the traditional process, the absorption rate and utilization rate of ozone were increased by 41.9% and 46.2%, respectively. The removal effect of AOM was also greatly improved, and ozone microbubbles enhanced the removal of aromatic protein-like substances and high-molecular-weight fulvic acid , humic acid and humic substances . The advantageous synergistic effect of ozone and microbubbles on algae removal was analyzed by exploring the enhanced air flotation removal mechanism of ozone microbubbles' enhanced air floatation removal. Good vacuole adhesion and strong oxidation caused by ozone microbubbles jointly guaranteed a good removal rate of AOM. The enhanced air flotation process with ozone microbubbles has high feasibility and a good effect, can effectively remove algal cells and algal pollutants, and has great potential in algal removal and control of water eutrophication.
研究领域:
环境科学
·
水处理工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）