MINERALS ENGINEERING
·
2018
·
IF 2.707
Zhili Li,Feng Rao,Ramiro Escudero García,Hongqiang Li,Shaoxian Song
The sodium oleate collector used in malachite flotation usually exhibits low selectivity. By partially replacing sodium oleate with alcohols, this study presents a method for increasing the selectivity of sodium oleate-based collectors in malachite flotation. By combining 3 × 10 −5 mol/L alcohols, such as 1-octanol, 2-ethylhexanol, and α-terpineol, with 1 × 10 −5 mol/L sodium oleate, malachite floatability values higher than 98% are achieved. Contact angle and zeta potential measurements reveal that the co-adsorption of alcohols with sodium oleate may be resulted from the hydrophobic interactions between their hydrocarbon chains. The co-adsorption of methyl isobutyl carbinol, along with its shorter hydrocarbon chain, makes it more difficult to render the malachite surface highly hydrophobic. However, the co-adsorption of straight-chain and branched-chain alcohols with sodium oleate shows the ability consistently to induce high malachite floatability.
研究领域:
矿物加工工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2024
·
IF 1.9
Zhanglei Zhu,Bohui Zhao,Jin Wang,Yiming Zhu,Qiuyue Sheng,Zhen Li,Ningning Zhang,Wei Yu
High-ash fine slime has an adverse effect on coal flotation. In this study, the roles of sodium silicate (SS) and sodium carbonate (SC) in the facilitating effect on lean coal flotation (a type of coking coal) were studied when sodium oleate (NaOL) was used as a collector through flotation tests, Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM-EDS) observations, turbidity measurements, and particle interaction energy calculations. The flotation tests found that SS has a stronger capacity than SC for the improvement of flotation performance of lean coal. Moreover, SEM-EDS observations and turbidity measurements showed that SS presents a stronger weakening effect for the coating of high-ash fine slime on the surface of low-ash coal particles than SC. Furthermore, the particle interaction energy calculations verified that the increase in the energy barrier for the attachment between low-ash coal particle and high-ash fine slime caused by SS is larger than SC, providing theoretical supports for the experiments. Compared to kerosene as a collector, based on the similar ash content, the yield of clean coal increases greatly with the synergistic effect of SS and NaOL. In summary, SS is an appropriate dispersant for lean coal flotation in sodium oleate system.
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
MINERALS ENGINEERING
·
2024
·
IF 4.9
Xinzhuang Fu,Ya Gao,Chuanxi Peng,Haisheng Han,Wei Sun,Tong Yue
The interaction of surfactants at minerals-water interfaces in flotation system plays an important role in minerals separation. Although the increasing number of reports have been published on the sodium oleate (NaOL) adsorption at the mineral–water interface, there has been little development in describing and predicting its adsorption behaviors from a quantitative molecular insight. In this study, based the adsorption experiments, the adsorption characteristics of NaOL on the hematite/quartz-water interfaces were quantitatively depicted using the surface complexation model (SCM). There was a monodentate binding form between the function group on NaOL and the hematite and quartz surface sites during SCM fitting. The binding constants (logK) of NaOL are 10.72 (≡Fe-OL) and 8.03 (≡Si-OL), respectively. Notably, there are more positive ≡FeOH 2 + site on the hematite surface, and it has strong adsorption capacity with anionic surfactant NaOL. Moreover, the minerals surface potentials, NaOL adsorption capacity and flotation recovery in mixed ore systems were successfully predicted by the model. This study provides a credible evaluation of the adsorption characteristics of NaOL under a broad scope of pH and concentration conditions. Meanwhile, quantitative analysis of surfactants adsorption at minerals-water interfaces is beneficial for the intelligence of mineral processing technology and efficient separation of minerals.
研究领域:
矿物加工工程
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界面化学
✓ 已验证
产品关联
DOI
高影响因子
POWDER TECHNOLOGY
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2021
·
IF 5.134
Wencheng Xia,Yuqiang Mao,Guangyuan Xie,Yaoli Peng
The filling of pores by flotation-reagent-contained water plays an important role in porous mineral flotation . This paper studied the role of sodium oleate (NaOL, a commonly used flotation reagent) solution in the in-situ wetting process of pores of porous active carbon using 1 H LF-NMR, FTIR as well as contact angle measurements. The floatability of active carbon particles wetted by NaOL solutions was evaluated by particles-bubble attachment measurements. The pore wetting percentage decreased as the NaOL concentration increased. The variation trend in pore wetting percentage by NaOL solutions was from fast to slow. Increasing the NaOL concentration contributed to achieve a lower pore wetting percentage as well as rate. The NaOL solution with a high concentration significantly improved the hydrophobicity of the sample, which further prevents the pore wetting process.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2018
·
IF 1.454
Dongfang Liu,Youlin Ma,Jiang Tan,Lu Wang,Quanwu Tang,Hongsheng Lu
We reported that the phase conversion of the micelles in aqueous solution prepared by sodium oleate (NaOA) and 3-(diethylamino)-propylamine (DEAPA) in the presence of carbon dioxide. This micellar structure is very sensitive to CO2 and the pH value of the solution is continuously reduced with the continuous introduction of carbon dioxide. When pH > 10.2, the mixed solution of NaOA and DEAPA is mainly in the form of spherical micelles; when the 10.2 > pH > 9.6, the mixed solution mainly in the worm-like micelles (WLM), where the solution has a significant viscosity change; when the 9.6 > pH > 9.1, the NaOA and DEAPA mixed solution becomes the aqueous two-phase system (ATPS), which is composed of two layers, the upper layer is the vesicle structure and the lower layer is the WLM structure; when the pH between 9.1 > pH > 9.0, NaOA and DEAPA mixed solution form vesicles, thus realizing the regulation of CO2 on the micellar structure transition of NaOA and DEAPA mixed solution. Such these microstructures transition could be confirmed by Rheology measurement, DLS and Cryo-TEM.
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2021
·
IF 5.221
Cheng Haijun,Wei Jiangli,Liang Min,Dai Suyi,Liu Xiongmin,Ma Li,Wang Hongyun,Lai Fang
Abstract: The synthesis costs of macrolide musks are higher than those of other commercial musks. To make this process less expensive, eggshell waste was calcined at a low temperature to obtain a catalyst for the cyclopentadecanolide production via reactive distillation using a glycerol entrainer. X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy analyses of the original and recovered catalysts revealed that the main catalytic ingredient was calcium glycerolate (CaG) and not calcium diglyceroxide (CaDG). The basic strengths of CaG and CaDG obtained by Hammett indicators were 7.2 < H_≤ 15.0 and 9.8 < H_≤15.0, while the corresponding base amounts were 1.9 and 7.3 mmol/ g, respectively. Because CaG was soluble in glycerine, the catalyst was efficiently reused. The reaction product containing over 95.0% cyclopentadecanolide with a yield of 49.8% was obtained at a temperature of 190°C and catalyst amount of 12 wt% after 7 h of reaction. Thus, eggshell waste may be directly placed into the reaction mixture after calcination at 600°C to synthesise a large amount of cyclopentadecanolide within a relatively short time. The results of this work indicate that eggshell waste can serve as a potential eco-friendly and affordable catalyst source for the production of macrolide musks.
研究领域:
化学工程
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环境科学
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有机合成
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2020
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IF 5.065
Zhao Chen,Danhua Xie,Binglei Song,Chaowang Li,Xiaomei Pei,Rong Li
A tetrameric monomer containing an azobenzene group (abbreviated as tetra-N(AZO)-Br) was synthesized in this paper, and a “pseudo” oligomeric surfactant was constructed using tetra-N(AZO)-Br and a traditional surfactant, sodium oleate (SO), by non-covalent bonded interaction. The synthesized tetra-N(AZO)-Br was characterized by 1 H NMR and UV–Vis spectra. The viscoelasticity and the difference in nuclear magnetic resonance (NMR) and ultraviolet (UV) absorption of the SO/tetra-N(AZO)-Br “quasi” tetrameric surfactant solution at different concentrations were investigated. The SO/tetra-N(AZO)-Br “pseudo” tetrameric surfactant could form highly viscoelastic worm-like micelles in solution, and the zero-shear viscosity of the system increased with increasing concentration. The viscoelastic properties of SO/tetra-N(AZO)-Br “pseudo” tetrameric surfactant had no obvious change after UV light irradiation . Since the combination of SO and tetra-N(AZO)-Br molecules was in dynamic equilibrium through the attraction of positive and negative charges, as much as 30% of the trans- tetra-N(AZO)-Br molecules in worm-like aggregates were transformed to their cis- structure. The un-transformed trans- tetra-N(AZO)-Br molecule could move in the aggregate and help maintain the structure of the aggregates, so that the viscosity had no obvious change.
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2022
·Vol. 15
·期 7
·2672
·
IF 3.748
Lifang Song,Huiwen Huo,Wenshuo Zhang,Huiyun Xia,Yanhui Niu
In order to improve the initial color and the long-term heat stability of super-transparent polyvinyl chloride (PVC), a series of composite heat stabilizers consisting of unsaturated Zn oleate and uracil derivatives have been designed in this paper. The uracil derivatives are 1,3-dimethyl-6-amino-uracil (DAU) and 6,6′-diamino-1,1′,3,3′-tetramethyl-5,5′-(ethylidene)bisuracil (OSU). The static thermal stability, dynamic thermal stability, and transparency were used to evaluate the properties of the stabilized transparent PVC sheets. The results indicate that the compatibility between the stabilizer and PVC was greatly enhanced by introducing an unsaturated long-chain Zn oleate and a long alkyl chain bisuracil derivative. Through the thermal discoloration test, the best ratio of DAU/zinc oleate (DAU/Zn) and OSU/zinc oleate (OSU/Zn) was determined to be 4:1, with a total amount of 3 phr in 100 phr PVC. It was verified that the combination of zinc oleate with uracil derivatives could improve the long-term thermal stability of PVC, and the DAU/Zn was better than that of the OSU/Zn. In addition, through the transmission/haze verification, adding a proper amount of epoxidized soybean oil (ESBO) and phosphite ester to the OSU/Zn system has a certain synergistic effect. The thermal stability and transparency of PVC can be remarkably enhanced.Keywords:polyvinyl chloride;highly transparency;zinc oleate;uracil derivatives;thermal stability
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
·
IF 5.518
Huili Han,Wanzhong Yin,Bin Yang,Donghui Wang,Jin Yao,Zhanglei Zhu
This work systematically studied the adsorption behavior of sodium oleate (NaOL) on hematite , limonite, and siderite and their corresponding flotation performance at alkaline pH . The adsorption behavior and conformation of NaOL on mineral surfaces were investigated using zeta potential analysis, Fourier-transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy spectra (XPS), and atomic force microscopy (AFM) imaging characterization. The effect of NaOL adsorption on the surface wettability and bubble-particle attachment was further analyzed by contact angle measurement, attachment time tests, and wrap angle tests. Finally, batch flotation tests and kinetic analysis were carried out to evaluate three mineral flotation behaviors. The results revealed that NaOL could chemically adsorb on hematite, limonite, and siderite and caused the significant negative mobility in their zeta potentials. It was found that Fe atoms exposed on their surface were the main active centers for the chemisorption of NaOL. Hematite and limonite had more active sites for NaOL adsorption than siderite, and Fe(III) on hematite and limonite surface could interact more strongly with NaOL than Fe(II) on siderite, which resulted in the higher adsorption density and intensity of NaOL on hematite and limonite than that on siderite. This further contributed to the stronger hydrophobicity on their surface than that on siderite surface. The enhancement of hydrophobicity could increase the attachment efficiency of bubble-particle ( E a ). Therefore, hematite and limonite particles had more and faster attachment with bubbles than siderite particles. As such, much higher cumulative ultimate recoveries ( R ∞ ) and flotation rate constants ( k ) of hematite and limonite than those of siderite were obtained.
研究领域:
矿物学
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表面化学
·
浮选工艺
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Xi Zhang,Mingzhu Huangfu,Jiushuai Deng,Yu Wang,Bozeng Wu,Mingzhen Hu,Honghui Zhao,Suozhi Wu
Specularite is generally recovered by flotation, but its floatability is relatively weak. Activation is an effective method to improve the floatability of minerals. Therefore, finding an economic and effective activator to improve the recovery of specularite is an important research direction. In this study, lead nitrate as an activator was found and confirmed to improve the floatability of specularite. Its activation mechanism was further investigated by various analytical methods. The micro-flotation tests results showed that the recovery of specularite increased from 69.57% to 92.47% at a Pb 2+ concentration of 3 × 10 -5 mol/L, an approximately 23% increase, indicating that Pb 2+ could obviously activate specularite. The SEM-EDS results illustrated that the content of Pb on the specularite surface apparently increased after specularite treatment with lead nitrate, which confirmed the adsorption of Pb species on the surface of specularite. Zeta potential results showed that the zeta potential positively shifted within the pH range from 3 to 11, which was beneficial to the occurrence of electrostatic adsorption and chemisorption between negatively charged oleate species and specularite. XPS results revealed that lead species mainly adsorbed on the O atoms of Fe-O and Fe-OH at the specularite surface, and Pb atoms became new sites to interact with sodium oleate. In addition, Pb 2+ and Pb(OH) + were the predominant components that interacted with the specularite surface and formed -O-Pb and Fe-O-Pb complexes, which considerably increased the number of reactive sites on the specularite surface. After oleate components interacted with Pb-modified specularite, a denser hydrophobic layer was generated on the surface of specularite, which intensified the floatability of specularite.
研究领域:
矿物加工
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材料科学
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化学工程
✓ 已验证
DOI
高影响因子
ACS Applied Electronic Materials
·
2024
·
IF 4.3
Jinyi Zhu,Zhe Wan,Wenlin Du,Xin Liu,Li Chen,Shuxia Li,Ning Kang,Chenglong Wang
Nickel oxide has become a promising alternative as a hole-transport layer employed in perovskite solar cells (PSCs). However, nickel oxide nanoparticles (NPs) are often necessary to form nickel oxide films, which may cause some microcracks, surface crystal defects, and nonuniformity in the prepared nickel oxide film. In this paper, a strategy is designed to bypass nickel oxide NPs to realize the in situ growth of a uniform nickel oxide film using nickel oleate as the precursor. Therefore, the prepared perovskite solar cells (PSCs) with the structure of FTO/NiO/MAPbI3/PC61BM/Ag exhibit a champion photoelectric conversion efficiency (PCE) up to 16.19%, compared with 11.71 and 9.15% for the prepared and commercial nickel oxide NPs, respectively. It is noted that this champion PCE (16.19%) is higher than those reported in studies on devices with identical structures. Moreover, the average short-circuit current (JSC), open-circuit voltage (VOC), and fill factor (FF) of devices based on the nickel oleate metal strategy are much higher than those prepared from NiO NPs by the sol–gel method (19.46 vs 17.24 mA/cm2, 1.072 vs 1.041 V, and 0.776 vs 0.653, respectively). This work provides a reliable avenue to generate nickel oxide films with increased uniformity and corresponding high-performance PSCs.
研究领域:
材料科学
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能源科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Xin Liu,Liping Yang,Li Chen,Shuxia Li,Peng Li,Yongrong Sun,Ning Kang,Chenglong Wang
It is still challenged to propose a straightforward and in-situ growth method of fabricating perovskite-type metal oxide films with dense and uniform surface coverage. This paper presents a simple strategy to prepare LaBO 3 (where B = Ni, Co, Fe, Mn) films by metal oleate (MO) route, in which metal oleates (La(OA) 3 and (B(OA) x , x = 2 or 3) serve as effective ligands to inhibit the self-aggregation among crystal grains. The as-prepared LaNiO 3 film with uniform and dense surface shows a reduced contact angle (31.5° vs 51.2°) and surface roughness (Ra = 14.2 vs 23.9 nm) compared with film prepared by Sol-gel (SG) method. Finally, the LaNiO 3 film by MO route is successfully employed as hole transport layer (HTL) in perovskite solar cells (PSCs) to obtain a power conversion efficiency (PCE) up to 15.62 %, which is 1.54 times that of PSCs by SG method. This work opens an avenue for fabricating LaBO 3 films with dense and uniform surface coverage by MO route.
研究领域:
材料科学
·
能源科学
✓ 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）