MICROPOROUS AND MESOPOROUS MATERIALS
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2021
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IF 5.455
Tao Jiang,Fumin Wang,Xubin Zhang,Yi Zhai,Guojun Lv,Yu Shen,Yuzhou Wu
Mesocrystal zeolite with well-defined morphology owns mesoporous channels and single crystal characteristics, which could promote diffusion efficiency, stability and catalytic activity. Thus, we performed the controllable synthesis of ZSM-5 mesocrystal without special additives and complex methods. Selected area electron diffraction (SAED) and fast Fourier transform (FFT) showed diffraction spots regardless of crystallization time, which indicated the well oriented feature of synthesized ZSM-5 zeolites. The crystallization process was further investigated. The oriented particle attachment (OPA) effectively guided the synthesis process of mesocrystals, which followed the nonclassical crystallization mechanism. The crystallinity curve exhibited valley-like shape, which manifested that the crystallization pathway went through three stages: fast precipitation, deconstruction and reorganization. The plausible formation mechanism was proposed, which might be useful for the fabrication of ZSM-5 mesocrystal. The prepared zeolites showed superior catalytic performance in aldol condensation reaction between benzaldehyde and 2-hydroxyacetophenone, obtaining 93% of the conversion.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
MINERALS ENGINEERING
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2021
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IF 4.765
Fangyu Guo,Qi He,Yaowen Xing,Youfei Zhang,Shihao Ding,Mengdi Xu,Xiahui Gui
Bubble-particle detachment is the key sub-process for determining the upper size limit of flotation . In this study, vertical adhesion force between particle and different positions on a bubble surface were measured using a micro-mechanical testing machine (MMTM). Three micrometer glass beads with varying hydrophobicities (hydrophilic, medium hydrophobic, and highly hydrophobic) were adhered to the end of the force sensor, and an air bubble with a diameter of 950 μm was fixed at the bottom of the hydrophobic quartz cell. Different contact positions were selected by gradually increasing the offset distance from the vertical axis of the bubble. The results showed that the back-calculated advancing contact angles of the hydrophilic, medium hydrophobic, and highly hydrophobic particles were 45, 86, and 124°, respectively. The vertical adhesion force always decreased with increasing offset distance, regardless of particle hydrophobicity. The decrease in the vertical component of the normal capillary force at the contact point might be the main reason for the decreased vertical adhesion force. Additionally, a linear region in the retraction force curves was always observed, illustrating that the bubble behaved as a Hooke’s spring under a vertical force. The spring constants at different positions on the bubble surface were found to decrease with increasing offset distance, which were consistent with the variations in vertical adhesion force observed.
研究领域:
矿物加工工程
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表面化学
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
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2024
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IF 4.9
Qi He,Chuanfu Chen,Qinglin Yin,Shihao Ding,Yijun Cao,Xiahui Gui,Yaowen Xing
Coarse particle separation is important in mineral processing. In this study, the performance of coarse chalcopyrite ore separation (−600 μm, Cu grade 0.375 %) by fluidized bed flotation (FBF) was investigated and the basic function of fluidized bed on the particle separation is discussed. The chalcopyrite grain size distribution mainly ranges from 50 to 300 μm, with over 80 % of the grains being liberated. The results indicate that the FBF system can reject tailings with a yield of 48 % and a Cu grade of 0.06 %. Additionally, concentrate Cu grade reaches 0.62 %, which is around 1.65 times higher than feed, resulting in a total Cu recovery of 91.55 %. The introduction of a fluidized bed increases Cu recovery of −600 + 300 μm from 50 % to73%, as it improves the possibility of bubble-particle attachment, but the variation of bed height has little influence. Particles with a size of −300 + 74 μm can obtain a 96 % Cu recovery in the bubbly flow, while particles with a size of −74 μm lose their separation effect due to hydraulic entrainment.
研究领域:
矿物加工
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冶金工程
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浮选技术
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Chemistry
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2024
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IF 6.7
ZhaoGuo Wu,XueZhi Zhou,Hao Chen,AiWu Zhao,Jin Wang
Controlling formation of metal organic frameworks (MOFs) with embedded enzymes on magnetic surface has been achieved by a confined growth with particle attachment driven self-sieving approach for the first time. Specifically, a versatile route of silica encapsulation guided enzyme assembly for formation of ZIF-8 shell has been successfully demonstrated by shaped-controllable Fe 3 O 4 nanoparticles , e.g., nanorod and nanocube. Interestingly, silica encapsulation can lead to structural diversity of ZIF-8 shell on the shaped-controllable Fe 3 O 4 nanoparticles for affecting properties of the nanocomposites. Furthermore, embedded enzymes confined between silica endoskeleton and ZIF-8 exoskeleton can participate in cascade reaction with different activities and stabilities in the terms of plasmonic assemblies fabrication and cancer cell catalytic therapy. As a result, a circulation plasmonic fabrication and cancer therapy can be achieved via the magnetic nanocomposites. It can be expected that the confined growth with particle attachment driven self-sieving method can be versatile to generate diverse MOFs shell encapsulated shaped-controllable nanoparticles for efficiently embedding enzyme in the nanocomposites.
研究领域:
材料科学
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纳米技术
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生物技术
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癌症治疗
✓ 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）