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Science China Chemistry 2012年第9期55卷 1825-1831页

作者： li YingFeng YU YangXin ZHENG YuanXiang li jiding Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

The effects of solid-fluid interactions on the vapor-liquid phase diagram,coexistence density,relative volatility and vaporization enthalpy have been investigated for confined binary systems of CO 2-CH 4,CO 2-N 2 and CH 4-N *** Gibbs ensemble Monte Carlo(GEMC) simulation results indicate that the confinement and the solid-fluid interaction have significant influences on the vapor-liquid equilibrium *** confinement and the strength of the solid-fluid interaction make the p-x i phase diagram move to higher pressure *** also make the two-phase region become narrower for each binary *** strength of the solid-fluid interactions can cause increases in the coexistence liquid and vapor densities,and cause the decrease of the relative volatility and the vaporization enthalpy for the systems *** the pore width is decreased,the two-phase region of the binary mixture becomes narrower.

关键词： Vapor-liquid equilibria slit-pore Gibbs ensemble Monte Carlo simulation vaporization enthalpy

Preparation of SGO-modified nanofiltration membrane and its application in SO_4^(2-) and Cl^- separation in salt treatment

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Journal of Environmental Sciences 2019年第4期31卷 183-192页

作者： Yanjun Zhang Changwei Zhao Shaofeng Zhang ling Yu jiding li li-an Hou School of Chemical Engineering Hebei University of Technology Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of Sciences The State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua University Xi'an High-Tech Institute

The lack of fresh water in the world makes the search for an effective method to decontaminate water an urgent *** important step is to remove different multivalent ions in salt ***(NF)has been used for treating water containing different kinds of *** this work,sulfonate group-modified graphene oxide(SGO)was prepared,and added during the interfacial polymerization(IP)reaction to prepare SGO-modifiedNF membranes(PA-SGO).The chemical composition,structure and surface properties of PA and PA-SGO membranes were characterized by FT-IR,XPS,SEM,AFM,contact angle and zeta potential *** water flux,salt rejection and antifouling abilities were investigated *** testing results showed that the water flux of PA-SGO(0.03%SGO)was 45.85 LMH under a pressure of 0.2 MPa,and the salt rejection varied in the order of Na_2SO_4(98.99%)>MgSO_4(91.25%)>MgCl_2(42.27%)>NaCl(21.96%).An anti-fouling experiment indicated that the PA-SGO membrane had good anti-fouling properties because of its decreased roughness and increased hydrophilicity and *** PA-SGO membrane has good potential for use in removing salt ions from water.

关键词： Water treatment Sulfonate group-modified graphene oxide NF Membrane Salt separation

Breakthroughs on tailoring membrane materials for ethanol recovery by pervaporation

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Chinese Journal of Chemical Engineering 2022年第12期52卷 19-36页

作者： Xia Zhan Xueying Zhao Zhongyong Gao Rui Ge Juan Lu Luying Wang jiding li Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National light Industry Beijing Technology and Business UniversityBeijing 100048China The Institute of Medicinal Plant Development The Chinese Academy of Medical Sciences(CAMS)and Peking Union Medical College(PUMC)Beijing 100193China Beijing Key Laboratory of lignocellulosic Chemistry Beijing Forestry UniversityBeijing 100083China The State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Bioethanol, as a clean and renewable fuel, has gained increasing attention due to its major environmental benefits. Pervaporation(PV) is a promising and competitive technique for the recovery of ethanol from bioethanol fermentation systems due to the advantages of environmental friendliness, low energy consumption and easy coupling with fermentation process. The main challenge for the industrial application of ethanol perm-selective membranes is to break the trade-off effect between permeability and selectivity. As membrane is the heart of the pervaporation separation process, this article attempts to provide a comprehensive survey on the breakthroughs of ethanol perm-selective PV membranes from the perspectives of tailoring membrane materials to enhance PV separation performance. The research and development of polymeric and organic/inorganic hybrid membranes are reviewed to explore the fundamental structure-property-performance relationships. It is found that mixed matrix membranes with welldesigned membrane structures offer the hope of better control overphysi-/chemical microenvironment and cavity/pore size as well as size distribution, which may provide both high permeability and membrane selectivity to break the trade-off effect. The tentative perspective on the possible future directions of ethanol perm-selective membranes is also briefly discussed, which may provide some insights in developing a new generation of high-performance PV membranes for ethanol recovery.

关键词： Pervaporation Ethanol recovery Microstructure Polymeric membrane Mixed matrix membrane

Effect of PEG additives on properties and morphologies of polyetherimide membranes prepared by phase inversion

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Frontiers of Chemical Science and Engineering 2010年第3期4卷 300-306页

作者： Jian CHEN jiding li Xia ZHAN Xiaolong HAN Cuixian CHEN Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

This study investigated the effect of poly(ethylene glycol)(PEG)additive as a pore-former on the structure formation of membranes and their permeation properties connected with the changes in thermodynamic and kinetic properties in the phase inversion *** membranes were prepared by using polyetherimide/Nmethyl-2-pyrrolidone/PEG(PEI/NMP/PEG)casting solution and water *** resulting membranes,prepared by changing the ratio of PEG to PEI,were characterized by scanning electron microscope(SEM)observations,measurements of water flux andγ-globin *** thermodynamic and kinetic properties of the membrane-forming system were studied through *** pore radius distribution curves were especially obtained by differential scanning calorimetry(DSC).Furthermore,the membranes were characterized for pure water flux and rejection of solute and by SEM *** filtration results agreed well with the SEM *** expected,PEG with a fixed molecular weight(PEG 600)acted as a pore forming agent,and membrane porosity increased as the PEG content of the casting solution increased.

关键词： phase inversion polyetherimide poly(ethylene glycol) additive

Drinking water treatment using a submerged internal-circulation membrane coagulation reactor coupled with permanganate oxidation

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Journal of Environmental Sciences 2017年第6期29卷 153-163页

作者： Zhongguo Zhang Dan liu Yu Qian Yue Wu Peiran He Shuang liang Xiaozheng Fu jiding li Changqing Ye Environmental Protection Research Institute of light Industry Beijing Academy of Science and TechnologyBeijing 100089China The State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China School of Public Health Nantong UniversityNantong 226019JiangsuChina

A submerged internal circulating membrane coagulation reactor （MCR） was used to treat surface water to produce drinking water. Polyaluminum chloride （PAC1） was used as coagulant, and a hydrophilic polyvinylidene fluoride （PVDF） submerged hollow fiber microfiltration membrane was employed. The influences of trans-membrane pressure （TMP）, zeta potential （ZP） of the suspended particles in raw water, and KMnO4 dosing on water flux and the removal of turbidity and organic matter were systematically investigated. Continuous bench-scale experiments showed that the permeate quality of the MCR satisfied the requirement for a centralized water supply, according to the Standards for Drinking Water Quality of China （GB B749-2006）, as evaluated by turbidity （〈1 NTU） and total organic carbon （TOC）（〈5 mE/L） measurements. Besides water flux, the removal of turbidity, TOC and dissolved organic carbon （DOC） in the raw water also increased with increasing TMP in the range of 0.01-0.05 MPa. High ZP induced by PAC1, such as 5-9 mY, led to an increase in the number of fine and total particles in the MCR, and consequently caused serious membrane fouling and high permeate turbidity. However, the removal of TOC and DOC increased with increasing ZP. A slightly positive ZP, such as 1-2 mV, corresponding to charge neutralization coagulation, was favorable for membrane fouling control. Moreover, dosing with KMnO4 could further improve the removal of turbidity and DOC, thereby mitigating membrane fouling. The results are helpful for the application of the MCR in producing drinking water and also beneficial to the research and application of other coagulation and membrane separation hybrid processes.

关键词： Membrane coagulation reactor(MCR)Polyaluminum chloride (PAC1)Hybrid membrane processPotassium permanganate (KMnO4)Drinking water

Solvent Recovery from Soybean Oil/Hexane Miscella by PDMS Composite Membrane

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Chinese Journal of Chemical Engineering 2011年第4期19卷 575-580页

作者： CAI Weibin SUN Yanzhi PIAO Xianglan li jiding ZHU Shenlin State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University Beijing 100084 China

Traditional solvent recovery in the extraction step of edible oil processing is distillation,which consumes large amounts of *** the distillation is replaced by membrane process,the energy consumption can be reduced *** this work,two kinds of membrane,PDMS(polydimethylsiloxane) composite membrane and Zeolite filled PDMS membrane were prepared,in which asymmetric microporous PVDF(polyvinylidenefluoride) membrane prepared with phase inversion method was functioned as the microporous supporting layer in the flat-plate composite *** different function compositions of the PDMS/PVDF composite membranes were characterized by reflection Fourier transform infrared(FTIR) *** surface and section of PDMS/PVDF composite membranes were investigated by scanning electron microscope(SEM).The PDMS NF(nanofiltration) membranes were then applied in the recovery of hexane from soybean oil/hexane miscellas(1:3,mass ratio).The effects of pressure(0.5-1.5 MPa),cross-linking temperature and PDMS layer thickness on membrane performances were *** results indicated that both two kinds of NF membranes were promising for solvent recovery,and zeolite filled in PDMS NF membrane could enhance the separation performance.

关键词： PDMS composite membrane miscella zeolite solvent recovery

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平板膜组件内部流体流动状态的可视化

化工学报 2014年第1期65卷 71-77页

作者：王涛展侠李继定清华大学化学工程系化学工程联合国家重点实验室北京100084 北京工商大学食品学院北京100048

自行设计了透明的有机玻璃膜组件,用于直接观测组件内部流体流动状态。分别测定了空流道和含有料液隔网流道的压力损失,并根据摩擦因子f随Re值的变化曲线确定了临界Reynolds数(Rec)的范围。结果表明,含有料液隔网流道的Rec相比空流道大... 详细信息

自行设计了透明的有机玻璃膜组件,用于直接观测组件内部流体流动状态。分别测定了空流道和含有料液隔网流道的压力损失,并根据摩擦因子f随Re值的变化曲线确定了临界Reynolds数(Rec)的范围。结果表明,含有料液隔网流道的Rec相比空流道大大减小。利用注射颜料的方法对流体流动情况进行观测,验证了上述结果。随后测定了表面粗糙度、隔网排布形式、孔隙率对流体流动情况的影响。最后,自制小型卷式膜进行测试,结果与平板膜的压力损失情况相符,表明平板膜的实验结果可以用于预测卷式膜的行为。

关键词：膜平板膜卷式膜流体力学料液隔网可视化湍动

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酚酞基聚芳醚砜非对称超滤膜凝胶动力学研究

高分子学报 2007年第11期17卷 1074-1079页

作者：李昕赵欣陈翠仙李继定北京理工大学化工与环境学院生态工业研究所北京100081 清华大学化工系北京100084

采用耐高温工程塑料——含酚酞侧基的聚芳醚砜(PES-C)为膜材料,草酸和聚乙二醇为添加剂,N,N-二甲基乙酰胺为溶剂,并利用改进的凝胶动力学实验装置和方法,使之能真实地再现不同膜孔结构生长及发展演化的过程,借助相关软件对图像进行处理... 详细信息

采用耐高温工程塑料——含酚酞侧基的聚芳醚砜(PES-C)为膜材料,草酸和聚乙二醇为添加剂,N,N-二甲基乙酰胺为溶剂,并利用改进的凝胶动力学实验装置和方法,使之能真实地再现不同膜孔结构生长及发展演化的过程,借助相关软件对图像进行处理,考察了添加剂、聚合物浓度对铸膜液凝胶速度的影响,对酚酞基聚芳醚砜非对称膜的凝胶过程的动力学进行研究.结果表明,动力学图像与最终膜结构有很好的一致性,凝胶动力学方面得到了与Strathman等不同的研究结果,发现凝胶前锋位移的平方与时间不是线性关系,凝胶动力学过程不能简单地用Fick扩散定律来描述.

关键词：凝胶动力学非对称膜相转化聚芳醚砜

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计算流体力学在膜过程传质优化中的研究进展

化工进展 2017年第6期36卷 1961-1968页

作者：何欣平王涛李祥李继定清华大学化学工程系北京100084

分别从膜组件、膜本身结构、膜过程操作条件、膜过程耦合4个方面的优化阐述了近期计算流体力学(CFD)在膜过程传质优化中的研究及应用进展。指出CFD模拟对料液隔网的形态研究和局限性改进显示出了优越性;在膜表面形貌及支撑层结构修饰与... 详细信息

分别从膜组件、膜本身结构、膜过程操作条件、膜过程耦合4个方面的优化阐述了近期计算流体力学(CFD)在膜过程传质优化中的研究及应用进展。指出CFD模拟对料液隔网的形态研究和局限性改进显示出了优越性;在膜表面形貌及支撑层结构修饰与优化方面发挥了关键作用;对脉动流、两相流与机械振动的引入及其在流场、浓度场、温度场中的可视化研究也已相对成熟;此外,CFD模拟证明,将膜过程与其他动态分离过程相耦合也是提高膜表面剪切速率、增强传质与分离效率的有效途径。指出了目前大部分CFD模拟工作的准确性还不够、通过模型优化改善准确性时会不可避免地增加模拟计算的复杂性以及膜组件的设计研究与材料加工工艺还不很匹配等存在的问题,认为该领域未来的发展方向将集中在不同优化方式的耦合,以及利用新兴的检测技术与制备工艺弥补目前实验数据缺乏的弊端,得到更贴合实际的理论模型。

关键词：计算流体力学膜分离传质优化形貌设计两相流

Measurement of liquid Diffusion Coefficients of Aqueous Solutions of Glycine, L-Alanine, L-Valine and L-Isoleucine by Holographic Interferometry

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Chinese Journal of Chemical Engineering 2005年第2期13卷 285-290页

作者：赵长伟李继定马沛生夏淑倩 Department of Chemical Engineering Tsinghua University Beijing 100084 China School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

The diffusion coefficients of aqueous solutions ofglycine, L-alanine, L-valine and L-isoleucine at 298.15 K were determined by holographic interferometry with accuracy and promptness while without disturbance. The density and viscosity of these solutions were also determined. According to original Gordon model, a model for correlating the diffusion coefficients of amino acids in aqueous solutions was developed and applied. The results showed that this model provided significant convenience in correlation of diffusion coefficients for amino acids system.

关键词： amino acid liquid diffusion coefficient holographic interferometry model