Minerals
·
2023
·Vol. 13
·期 10
·1322
·
IF 2.5
Xiaoliang Zhang,Yangge Zhu,Zhiqiang Zhao,Peilong Wang
Dolomite, a prominent calcium-bearing gangue mineral found in carbonate-type zinc oxide ores, poses a significant challenge for effective flotation separation alongside smithsonite due to their highly similar surface properties. The present study explores the potential of 2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctanoic acid (2-DMPT) as a collector for the reverse flotation of smithsonite from dolomite. Micro-flotation experiments indicated that saponified 2-DMPT exhibited superior collecting ability and selectivity for dolomite over smithsonite under highly alkaline conditions. Specifically, the flotation recovery of dolomite reached 62%, whereas only 6% of smithsonite was recovered in the flotation foam products. Zeta potential and attenuated total reflectance–Fourier transform infrared (ATR-FTIR) analysis revealed that changes in pH values had minimal influence on the collector’s adsorption onto dolomite, while significantly hindering its adsorption on the smithsonite surface. Furthermore, X-ray photoelectron spectroscopy (XPS) analysis showed that 2-DMPT could form hydrophobic complexes with the active Ca2+sites on the dolomite surface at pH 11.5. However, the interaction between smithsonite and carboxylic groups of 2-DMPT under the same conditions was relatively weaker, facilitating their reverse flotation separation. As a result, 2-DMPT shows promise as a potential collector for the reverse flotation process, effectively removing dolomite from smithsonite and reducing acid consumption in subsequent acid-leaching processes.Keywords:smithsonite;dolomite;reverse flotation;highly alkaline conditions;saponified 2-DMPT
研究领域:
矿物加工工程
·
表面化学
✓ 已验证
DOI
高影响因子
PETROLEUM SCIENCE AND TECHNOLOGY
·
2019
·
IF 1.07
Lin Li,Xuwei Liu,Huijing Wang,Chaocheng Zhao,Qiyou Liu,Xiufang Shang
Environmental adaptability and biodegradability of oil pollutants on functional bacteria are two important keys to bioremediation technologies. Pseudomonas sp. LKY-5 revealed strong biological activities in high salinity (3%) and high alkalinity (pH 9.0). N-hexadecane, phenanthrene, pyrene and carbazole could be directly utilized, and inhibited by the presence of DBT. Sulfur compounds and alkanes in No. 0 diesel and FCC diesel were effectively degraded. The concentrations of short chain alkanes were increased significantly after degradation. It can be seen that strain LKY-5 is an excellent bacterial candidate for bioremediation of oil-contaminated sites and sediments.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
ANTI-CORROSION METHODS AND MATERIALS
·
2024
·Vol. 71
·期 4
·391-402
·
IF 2.3
Hang Jia,Zhiming Gao,Shixiong Wu,Jia Liang Liu,Wenbin Hu
PurposeThis study aims to investigate the corrosion inhibitor effect of migrating corrosion inhibitor (MCI) on Q235 steel in high alkaline environment under cathodic polarization.Design/methodology/approachThis study investigated the electrochemical characteristics of Q235 steel with and without MCI by polarization curve and electrochemical impedance spectroscopy. Besides, the surface composition of Q235 steel under different environments was analyzed by X-ray photoelectron spectroscopy. In addition, the migration characteristic of MCI and the adsorption behavior of MCI under cathodic polarization were studied using Raman spectroscopy.FindingsDiethanolamine (DEA) and N, N-dimethylethanolamine (DMEA) can inhibit the increase of Fe(II) in the oxide film of Q235 steel under cathodic polarization. The adsorption stability of DMEA film was higher under cathodic polarization potential, showing a higher corrosion inhibition ability. The corrosion inhibition mechanism of DEA and DMEA under cathodic polarization potential was proposed.Originality/valueThe MCI has a broad application prospect in the repair of damaged reinforced concrete due to its unique migratory characteristics. The interaction between MCIs, rebar and concrete with different compositions has been studied, but the passivation behavior of the steel interface in the presence of both the migrating electric field and corrosion inhibitors has been neglected. And it was investigated in this paper.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Guangwei He,Mingzhao Xu,Zongyu Li,Shaofei Wang,Shentao Jiang,Xueyi He,Jing Zhao,Zhen Li,Xingyu Wu,Tong Huang,Chaoyi Chang,Xinlin Yang,Hong Wu,Zhongyi Jiang
The creation of interconnected ionic nanoaggregates within solid electrolytes is a crucial yet challenging task for fabricating high-performance alkaline fuel cells. Herein, we present a facile and generic approach to embedding ionic nanoaggregates via predesigned hybrid core–shell nanoarchitecture within nonionic polymer membranes as follows: (i) synthesizing core–shell nanoparticles composed of SiO2/densely quaternary ammonium-functionalized polystyrene. Because of the spatial confinement effect of the SiO2 “core”, the abundant hydroxide-conducting groups are locally aggregated in the functionalized polystyrene “shell”, forming ionic nanoaggregates bearing intrinsic continuous ion channels; (ii) embedding these ionic nanoaggregates (20–70 wt %) into the polysulfone matrix to construct interconnected hydroxide-conducting channels. The chemical composition, physical morphology, amount, and distribution of the ionic nanoaggregates are facilely regulated, leading to highly connected ion channels with high effective ion mobility comparable to that of the state-of-the-art Nafion. The resulting membranes display strikingly high hydroxide conductivity (188.1 mS cm–1 at 80 °C), which is one of the highest results to date. The membranes also exhibit good mechanical properties. The independent manipulation of the conduction function and nonconduction function by the ionic nanoaggregates and nonionic polymer matrix, respectively, opens a new avenue, free of microphase separation, for designing high-performance solid electrolytes for diverse application realms.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2022
·
IF 6.14
Lijing Zhang,Jiaqi Han,Yuchao Wang,Wenbo Yang,Shengyang Tao
Achieving a room-temperature Suzuki–Miyaura coupling (SMC) with high efficiency is of great significance to the development of low-carbon organic synthesis. Nevertheless, it is still a great challenge to construct a promising nanocatalyst with high activity for room-temperature SMC reaction. In this paper, a strong alkaline-supported nanocatalyst Pd/Mg(OH)2/MgO–ZrO2 was rationally developed based on MgO–ZrO2 hybrid nanofibers. Physicochemical characterizations present that the in situ conversion of MgO to Mg(OH)2 on the surface of the nanofibers results in a great increase in surface alkalinity of the carrier. The strong alkalinity can greatly accelerate the oxidation addition and transmetalation of the SMC process, resulting in the obvious reduction of activation energy of the reaction (Ea = 9.0 kJmol–1 for Ph–Br). The coupling conversion can reach up to 100% at room temperature within 8 min with a maximum TOF > 6516 h–1. It also shows an excellent performance in substrate applicability and chlorobenzene activation. The rational design of a high-basicity catalyst for room-temperature SMC will be a rewarding attempt for the development of low-carbon green organic synthesis.
研究领域:
催化化学
·
有机合成
·
纳米材料科学
✓ 已验证
产品关联
DOI
高影响因子
AICHE JOURNAL
·
2023
·Vol. 69
·期 6
·e18054
·
IF 3.7
Feng Xiong,Chen Ji,Shengzhi Gan,Peng Liang,Yi Huang,Jin Shang,Baoyu Liu,Jinxiang Dong
Mesoscopically structured ZSM-5 nanosheets were prepared as highly active catalysts for the alkylation between toluene with methanol. The results showed that the Brønsted acid sites of ZSM-5 nanosheets were mainly distributed on the external surface in aluminum-rich zeolites owing to the charge-balance between positive quaternary ammonium cation (N + ) in C ph-10-6-6 , Na + ions and negative aluminosilicate species. In addition, it revealed that high alkalinity was easier to depolymerize the Si O Si species in Aluminum-rich synthesis gel, and the high alkalinity was required for silica-rich systems to dissolve silica species in order to finish the self-assemble process, leading to ZSM-5 nanosheets with high alkalinity presenting enhanced catalytic performance. Moreover, the optimized ZSM-5-50-2.5 was effective for the alkylation between toluene and methanol with toluene conversion of up to 50%, and it was stably operated for 48 h under the harsh conditions of WHSV = 32.5 h −1 with a desired stability.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 55
·期 11
·4701-4716
·
IF 3.553
Ma Jianfeng,Zhao Hongxia,Shang Yazhuo,Peng Changjun,Liu Honglai,Zheng Shuzhen,Wang Tao,Qi Shuai,Ran Qianping
Abstract The presence of a highly alkaline environment or large amounts of Ca 2+ in concrete exerts a great influence on the dispersion of graphene oxide (GO) particles. Therefore, the development of a highly efficient GO dispersant to adapt to complex concrete environments is important. In this work, novel phosphate-modified small molecular polydentate polymers were synthesized and used as efficient dispersants for cement and high-concentration GO solutions. The chemical structure of the polymers was confirmed by 1 H NMR and IR spectroscopy, and the effect of adsorption groups on the adsorption ability of polymers was studied by using adsorption experiments and theoretical calculations. Results showed that the dispersant inositol hexaphosphate–methoxy polyether (IHP-MP) features a high adsorption equilibrium constant and strong adsorption ability. IHP-MP exhibited not only good water-reducing and slump-retaining properties but also remarkable cement hydration-retarding effects due to its numerous phosphate groups. IHP-MP could be used as an auxiliary GO dispersant with the comb polymer PCE to effectively reduce the viscosity and improve the stability of GO solutions. SEM, TGA and IR characterization indicated that IHP-MP strongly interacts with the surface groups of GO particles. Graphic Abstract
研究领域:
材料科学
·
化学工程
·
聚合物化学
·
土木工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）