Minerals
·
2018
·Vol. 8
·期 4
·149
·
IF 1.835
Weiqing Wang,Jinyao Cong,Jie Deng,Xiaoqing Weng,Yiming Lin,Yang Huang,Tiefeng Peng
The effect of hydrofluoric acid (HF) pretreatment on flotation of feldspar and quartz using dodecylamine (DDA) as collector was investigated by micro-flotation, zeta potential, pyrene fluorescence spectroscopy, attenuated total reflection flourier transformed infrared spectroscopy (ATR-FTIR), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and bench scale flotation. The micro-flotation tests revealed that there was little difference in the flotation of feldspar and quartz at pH 2, using H2SO4as pH regulator. After HF pretreatment, the floatability of feldspar significantly increased while the floatability of quartz showed no change. HF pretreatment resulted in leaching of SiO2and enrichment of Na, K and Al on the feldspar surface. Consequently, the negative surface charge of feldspar increased at pH 2, which allowed for the flotation separation of the feasible minerals. This took place via an increased electrostatic adsorption between DDA and Na, K, Al on the feldspar surface, which effectively increased its hydrophobicity and as a result, improved the floatability of feldspar. An alternative process which exhibited effective separation of quartz and feldspar while recycling the tailwater from the flotation was proposed.Keywords:hydrofluoric acid;flotation;DDA;ATR-FTIR
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 MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Zhonghua Xue,Yali Feng,Haoran Li
Investigating the reverse flotation desilication process of magnesite tailings (MT) holds substantial merit in the context of magnesium metal recovery from solid waste. However, scant attention has been devoted to exploring the influence of the carbon chain length of diverse alkanes on the reverse flocfloatation desilication of MT. This research systematically delved into the selective adsorption behavior exhibited by dodecylamine (DDA) and its compound collectors on the surfaces of quartz and magnesite. As the carbon chain length of alkanes increases, the efficacy of reverse flotation desilication of MT diminishes. Under optimized conditions, the concentration of MgO in the concentrate registers a 0.93% increment, accompanied by a 2.05% reduction in SiO 2 content. The optimal MgO grade attains 42.68%. The augmenting carbon chain length of alkanes leads to a decline in the dispersibility of the compound collector and a reduction in the diffusion coefficient of the monolayer film at the alkane/water interface. The compound collector, comprising n-heptane and DDA, manifests a noteworthy synergistic promotion effect on the flotation desilication of MT. This effect reduces the multilayer adsorption of DDA, promotes more hydrogen bonding formation, and favors DDA adsorption on the quartz surface over magnesite. Consequently, issues related to froth entrapment and poor selectivity are alleviated. Longer alkane chains in the compound collectors result in a stronger van der Waals force effect between the carbon chains. This effect causes DDDA to slide more easily on the quartz surface, which is not conducive to enhancing the hydrophobicity of the surface. Furthermore, alkane-induced hydrophobic flocculation increases the floccules size of quartz, enhancing the likelihood of bubble-particle adhesion. This investigation elucidates the molecular-level mechanism underlying alkane hydrophobic flocculation with varying chain lengths, contributing a theoretical foundation and technical support for the large-scale MT management and the sustainable production of magnesium metal.
研究领域:
矿物加工工程
·
材料科学与工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2025
·
IF 4.6
Jian Yang,Xiang Liu
The dense surface functional groups of carbon dots (CDs) provided several reactive sites for chemical modifications that might extend applications of CDs. Herein, we tried to modify nitrogen-doped CDs chemically which obtained by pyrolysis of citric acid and β-alanine with n-dodecylamine in aqueous medium for manufacturing cationic CDs surfactant (represented with NCDs-C12). The dilute solution of NCDs-C12 performed outstandingly in declining the surface tension of water from 72.0 to 32.0 mN m −1 , which was comparable to several new types of cationic surfactants. NCDs-C12 solution (in water medium) was apt to foam, which was by far better than that of some typical surfactants at the same concentration. Additionally, NCDs-C12 was positive charged and behaved perfectly in inhibiting the growth of E. coli or S. aureus . None of any organic solvent was used during the whole procedure. We herein provided a novel route of manufacturing a surfactant with renewable substances.
研究领域:
材料科学
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化学工程
·
生物学
✓ 已验证
产品关联
DOI
高影响因子
POWDER TECHNOLOGY
·
2019
·
IF 3.413
Bin Luo,Quanjun Liu,Jiushuai Deng,Li Yu,Hao Lai,Chao Song,Shimei Li
Beneficiation of zinc from low-grade oxidized zinc ores has become the focus of recent studies. Sulfidation is an important process to recover zinc from oxidized zinc ores in flotation . Although some studies have reported on the sulfidation-flotation of smithsonite, the effect of sulfide ions on sulfide film thickness remains unknown when the oxidized zinc ores start floating and achieve excellent flotation. In this work, the influence of sulfur ions on smithsonite flotation in a dodecylamine system were investigated by micro-flotation experiments, inductively coupled plasma-atomic emission spectrometry (ICP-AES), zeta potential measurements, X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (TOF-SIMS). Micro-flotation experiment results show that smithsonite starts floating after treatment with a low S concentration of 5 × 10 −5 mol/L, while excellent flotation was obtained following treatment with a high S concentration of 5 × 10 −4 mol/L. Compared to the low S solution, excellent hydrophobicity of smithsonite was obtained owing to the adsorption of more sulfide ions, making the mineral surface potential more negative, and forming a thicker heterogeneous zinc-sulfide film that primary consists of zinc monosulfide and zinc polysulfide . The zinc-sulfide film thickness on the smithsonite surface was approximately 7.79 nm when the smithsonite started floating, while excellent floatation was obtained as the zinc-sulfide film thickness reached about 12.13 nm.
研究领域:
矿物加工工程
·
冶金工程
✓ 已验证
DOI
高影响因子
MINERALS ENGINEERING
·
2021
·
IF 4.765
An Liu,Pan-pan Fan,Feng Han,Hua Han,Zhi-hong Li,Huai-fa Wang,Min-qiang Fan
In this study, the electroflotation of quartz and magnetite with cationic collector dodecylamine (DDA) and anionic collector sodium oleate (NaOL) were investigated to gain a better understanding of the electroflotation process and identify methods to improve it. An interesting phenomenon accompanied with obvious promotion (NaOL is used as collector) and inhibition (DDA-HCl is used as collector) of quartz flotation was observed after electrolysis. The obvious promotion arouse from the supply of the metal cations as active site for the adsorption of negatively charged group and increase active collecting species ionic forms RCOO - and (RCOO) 2 2– . Conversely, the obvious inhibition originated from the decrease of the active collecting species RNH 3 + and (RNH 3 ) 2 2+ . An obvious inhibition phenomenon was observed after the electrolysis for the magnetite. This is because the active collecting species RNH 3 + , (RNH 3 ) 2 2+ , RNH 2 ·RNH 3 + and RCOOH molecule decreased significantly after electrolysis. Furthermore, a comparison test between the regular flotation and electroflotation was conducted in the reverse flotation of magnetic separation concentrate. Compared with the regular flotation process, electroflotation flotation was characterized by simple reagent regime (without pH regulator and activator) and moderate conditions (natural pH), which had mild operation condition superiority. Moreover, the flotation product index of electroflotation can be better through slightly adjusting the reagent regime, and it can be certain that electroflotation is an effective process in the reverse flotation of magnetite. These findings provided a novel perspective for understanding the electroflotation process.
研究领域:
矿物加工工程
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浮选化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Yajun Zhao,Ji'an He,Tianpeng He,Lingrui Chen,Lu Lai,Xuemin Yan,Weichu Yu,Yuanzhu Mi
The discharge of oily wastewater not only has an impact on the environment, but also poses a threat to human health. Therefore, the treatment of oily wastewater is crucial. In current work, a novel demulsifier (CD-LA) was prepared using β-cyclodextrin (β-CD) as raw material by the acylation of –OH and subsequent grafting of dodecylamine. The demulsifier was intended for the treatment of oily wastewater. Detailed examinations were conducted on the surface morphology, chemical composition, interfacial activity, and the capacity of CD-LA to engage competitively at the interface. This substance demonstrated a pronounced ability to lower interfacial tension, indicating its utility in supplanting asphaltenes at the oil–water boundary. This action facilitates the weakening or disruption of the interfacial film, which is critical for the successful separation of oily wastewater. The findings revealed that CD-LA excelled in clarifying oily wastewater, proving effective under near-neutral conditions and in environments with elevated salinity. Separated water phase could obtain light transmittance (W T ) of 89.75 % and oil removal rate (W R ) of 99.83 % after the oily wastewater was demulsified with a concentration of 50 mg/L at room temperature.
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
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Di Meng,Haipeng Xie,Bin Yan,Weixuan Zhao,Yiming Fu,Wenjihao Hu,Yongli Gao
Quartz is a key raw material in high-tech fields (such as photovoltaics and semiconductor microelectronics), and the most efficient extraction method of quartz is mineral flotation. Quartz activation plays a crucial role in mineral flotation. However, the mechanism underlying the process remains unclear, and the role of additional metal ions is controversial. In this study, the interaction forces between the quartz surface, the dodecylamine (DDA) cation/sodium oleate (NaOL) anion mixed collectors, and Ca2+ were analyzed using atomic force microscopy in order to systematically explore the activation process of quartz flotation. The results confirmed that the activation process was initialized from NaOL, which was adsorbed on the surface of a calcium-covered quartz surface. The existence of DDA inhibited the binding of Ca2+ to NaOL so that more Ca2+ was adsorbed on the quartz surface to provide the adsorption site for NaOL. Moreover, the best adsorption condition of Ca2+ + NaOL + DDA mixed solution was analyzed by quartz crystal microbalance with dissipation, and it demonstrated that the most stable chemisorption environment on the quartz surface was at pH 11.0. In these circumstances, Ca2+ could first adsorb in a point-like manner on the quartz surface, which was then adsorbed with a mixture of NaOL and DDA. This result showed that, at a specific pH, Ca2+ could encourage the coadsorption of cationic/anionic mixed collectors on quartz. This work provides an important new understanding of the intermolecular interactions that take place during complex mineral flotation processes between chemical additives and mineral surfaces. The methodology used in this study can be easily adapted to different interfacial processes, including water treatment, membrane technology, bioengineering, and oil production.
研究领域:
矿物浮选
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界面化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MINERALS ENGINEERING
·
2020
·
IF 3.795
Xiaoxiao Qiao,An Liu,Zhihong Li,Jinchuan Fan,Canjin Luo,Panpan Fan,Yizhou Liu,Minqiang Fan
A novel combined reagent dodecylamine (DDA)–2-octanol–kerosene was employed to overcome the problems associated with DDA, that is, DDA has a high freezing point and needs to be acidified with hydrochloric or acetic acid when it is used for flotation. The analysis of the basic physical properties of the agent showed that DDA–2-octanol–kerosene had significant advantages in freezing point and dispersibility and its freezing point can be reduced to below 0 °C. From the flotation results of magnetite, it can be seen that DDA–2-octanol–kerosene has a better selectivity. Response Surface Methodology based on a three-level, three-variable Box–Behnken design (BBD) was employed to define the quadratic relationship between the recovery of quartz and the composition of the mixed agent. The results indicated that the recovery of quartz increased with the increase of DDA or 2-octanol dosage, however, kerosene had a marginal positive effect on the recovery of quartz when the amount of kerosene was less than 0.76 times that of DDA and otherwise a negative effect. This study provides a new method and technical support for its industrial application for the reverse flotation of iron ore for the combination of agents in the field of iron ore flotation. And allows for a deeper macro-level understanding of the interaction between the DDA–2-octanol–kerosene ternary mixed agents.
研究领域:
矿物加工工程
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化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2013
·Vol. 69
·期 1
·9-16
·
IF 1.66
Hu Qing,Chen Xiaofeng,Zhao Naru,Li Yuli,Mao Cong
This paper reports a facile method for fabricating monodispersed mesoporous bioactive glass sub-micron spheres (MBGS) using dodecylamine (DDA) as a catalyst and template agent in sol–gel process. The effects of synthesis conditions including the amount of DDA, temperature of hydrolysis and the volume ratio of alcohol to water (AW ratio) on the resulting particle size, morphology, monodispersity and pore size distribution of MBGS are investigated and discussed. The results indicate that the particle size, morphology, monodispersity and pore size distribution of MBGS depend on the amount of DDA, the temperature of hydrolysis and the AW ratio. Meanwhile, using DDA as the structure directing agent and hydrolysis catalyst under optimal synthesis conditions (e.g. 4 g DDA, hydrolysis temperature at 40 °C and AW ratio at 4) is in favor of obtaining MBGS with mesoporous surface structure, large specific surface area (362.073 m 2 g −1 ), relatively homogeneous particle size (~560 nm) as well as good apatite-forming activity. The unique structure and properties may turn MBGS into a good candidate as a drug delivery carrier or an injectable biomaterial for bone tissue regeneration.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
·
2020
·
IF 3.795
Peng Yang,Xianzhi Hu,Futing Zi,Baomin Yang,Qiang Wang,Yunlong Chen,Shuliang Chen
Because it is difficult to hydrophobically agglomerate fine kaolinite particles to obtain stronger, larger flocs using only dodecylamine (DDA) as a flocculant , octanoic acid (OA) was used as a synergistic flocculant to improve DDA-induced fine-kaolinite particle agglomeration. Particle settlement tests were conducted to study flocculation and synergistic flocculation behaviours of fine kaolinite particles for different DDA and/or OA concentrations. Results showed that OA strengthened DDA-induced particle agglomeration. Aggregate sedimentation rates and Stokes’ equivalent diameters exceeded 21.7 m/h and 84.4 µm, respectively. A clearer kaolinite suspension was obtained and a more compact aggregate layer accumulated within 3 min. Contact angles and Fourier-transform infrared (FTIR) spectroscopy were used to investigate kaolinite hydrophobicity before and after hydrophobisation and mechanisms of DDA and/or OA interactions with the kaolinite surface. Results suggested that faster sedimentation and larger equivalent-diameter aggregates were both related to significantly increased kaolinite-surface hydrophobicity. FTIR data confirmed that enhanced kaolinite surface hydrophobicity was owed to DDA and OA physisorption . The kaolinite micro-particle aggregation mechanism was analysed by SEM images. Kaolinite particle self-aggregation changed after OA was adsorbed on the kaolinite Si–O basal plane. Owing to DDA/OA synergistic effects, kaolinite particles hydrophobically agglomerated by actions of Al–O/Al–O and Al–O/Si–O faces, thereby promoting fine-kaolinite particle agglomeration and sedimentation. Study findings could lead to development of enhanced water-purification methods.
研究领域:
矿物加工工程
·
环境科学与工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Hui Shao,Bingqiao Yang,Huihua Luo,Ruiqi Ge,Jie Wu
In this study, N-OSS combined with DDA was examined as an novel collector. The collecting performances and their synergetic interaction mechanisms were investigated comprehensively. The micro-flotation results illustrated N-OSS/DDA exhibited excellent selectivity on separation without pre-activation. Contact angle tests revealed N-OSS/DDA could selectively enhance the hydrophobicity of spodumene, whereas, they barely affected that of albite. FTIR, SEM-EDS and Zeta potential revealed N-OSS/DDA might co-adsorb on spodumene surface rather than that of albite. XPS analysis and DFT calculations inferred the O 1 2p orbitals of -COO- within N-OSS could bond with Al 3s orbitals and the -NH 3 + groups of DDA adsorbed onto spodumene surface via hydrogen bonding and electrostatic attraction. Meanwhile, the hydrogen bonding between N-OSS and DDA promoted the co-adsorption on spodumene surface. While N-OSS/DDA weakly adsorbed on albite surface through physical adsorption. N-OSS/DDA exhibited outstanding floatability, which maybe a good substitute for conventional collectors in future.
研究领域:
矿物加工工程
·
表面化学
✓ 已验证
DOI
高影响因子
MINERALS ENGINEERING
·
2021
·
IF 4.765
Bin Yang,Ya-Feng Fu,Wan-Zhong Yin,Qiu-Yue Sheng,Zhang-Lei Zhu,Xue-Ming Yin
In this study, laurylamine ethoxylate with fifteen ethoxylate units (LAEO-15) was employed as a quartz collector for the recovery of malachite from quartz via reverse flotation. Its collecting performance and adsorption mechanism were evaluated by flotation tests and surface analyses. The results of flotation tests suggested that LAEO-15 had an intense ability to collect quartz instead of malachite, and displayed a high flotation selectivity, which promoted the significant floatability differences of both minerals. XPS confirmed that quartz adsorbed a much larger quantity of LAEO-15 than malachite, resulting in the selective collection of quartz with LAEO-15. Zeta potential and FTIR characterization further uncovered that the strong adsorption of LAEO-15 was driven by hydrogen bonding and electrostatic attraction, while electrostatic repulsion hindered the LAEO-15 adsorption on the surface of malachite. As a result, the effective separation of malachite and quartz was realized with 20 mg/L LAEO-15 at pH 6.30 via reverse flotation, in which 92.54% of malachite was recovered and 92.72% of quartz was removed, coupled with a high SI value of 12.57 in concentrate. Therefore, compared with conventional collector dodecylamine, LAEO-15 exhibited high selectivity and purification effectiveness for the separation of malachite from quartz.
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
危险品化学品经营许可证（带存储）