渗透蒸发和化学反应的耦合

渗透蒸发是分离液相混合物的膜分离方法，常用于有机物脱水及有机物－－有机物的分离。借助于渗透蒸发把化学反应产物部分或全部从反应体系中脱去，可使产物收率不受化学平衡的限制。     

聚氨酯渗透蒸发膜的研究进展

综述了聚氨酯渗透蒸发膜在渗透蒸发分离中的研究进展,分析了聚氨酯膜软硬段结构及其它因素对其分离性能的影响,并对聚氨酯膜的改性方法进行总结和评述。指出了聚氨酯膜目前研究中存在的不足及发展趋势。     

渗透蒸发膜及其在酯化反应过程中的应用

根据３０余篇文献及有关的技术资料，从膜的结构，膜制备的材料，制备方法及表征等方面总结了近１０年来渗透蒸发膜国内外的研究情况，以及将渗透蒸发膜应用酯化反应体系的研究成果和动态。     

沸石膜渗透蒸发性能研究进展

渗透蒸发由于其对近沸物和恒沸混合物高效的分离性能而成为当今一个基本的分离操作单元。本文首先对渗透蒸发装置及分离性能表征简要总结,然后重点概述了对沸石膜的渗透蒸发应用和渗透蒸发过程影响因素,最后针对当前研究现状,展望了沸石膜在渗透蒸发方面的发展前景。     

新型渗透蒸发膜的应用

本文介绍新型渗透蒸发膜的结构、工作原理和各种应用。     

渗透蒸发与化学反应耦合过程的研究进展

渗透蒸发膜分离过程往往不是单独应用 ,而是与其它的分离或反应过程进行耦合的。着重介绍了渗透蒸发膜分离过程与精馏和反应耦合过程的研究现状 ,以及讨论了渗透蒸发膜分离过程与化学反应耦合过程的数学模型和常用的渗透蒸发膜材料。     

分子筛膜渗透蒸发技术研究进展

概述了渗透蒸发膜分离过程和分子筛膜的优点,重点综述了沸石分子筛膜在渗透蒸发中的传输机理和传质模型,以及温度、压力、组成等对渗透蒸发膜分离性能的影响因素,介绍了分子筛膜渗透蒸发技术在有机溶剂脱水、水中脱除有机物和有机混合物分离等方面的应用,展望了分子筛膜在渗透蒸发膜分离技术中的发展方向。     

渗透蒸发膜改性技术的研究进展

物理改性和化学改性作为改变渗透蒸发膜的分离性能 (渗透通量和分离因子 )、抗污染性、物理化学稳定性的有效手段而吸引了大量的研究和开发兴趣。这些改性方法在不少场合下可以联合使用。对常用的改性方法进行了分类介绍 ,简要评述了各种方法的优缺点 ,并列举了一些实例加以具体说明     

交联聚乙烯醇渗透蒸发膜用于酯化反应过程

研究了交联聚乙烯渗透蒸发膜在酯化反应过程中的应用，以乙酸与正丁醇酯化反应为实验对象，通过渗透蒸发膜选择性地移走产物水，使最终反尖转化率超越平衡转化率，实验考察了温度，进料初始摩尔比，催化剂浓度对过程的影响。     

纸张干燥中湿分扩散系数的估算

纸张干燥过程涉及到多孔介质的热质传递,如何确定质量扩散系数是所建立的多孔物料湿分扩散模型能否进行数值计算的关键。按Liukov公式将湿分扩散系数视为含湿质量分数的非线性函数,在恒温下进行纸张干燥实验,通过比较湿分蒸发质量的测量值与理论计算值,采用多变量寻优的方法对多孔介质一维情况下的湿分扩散系数进行估算,得到了实验条件下的纸张湿分扩散系数的计算公式。并进一步确定了纸张中的湿分扩散系数与含湿质量分数和温度之间的函数关系式。     

Analytical models for predicting penetration depth during slot die coating onto porous media

A series of analytical models have been developed to predict the penetration depth during slot die coating on porous media. Analytical models for both Newtonian and non‐Newtonian fluids were derived based on Lubrication Theory, Darcy's law, and a modified Blake–Kozeny equation. Using these models, the penetration depth can be quickly solved and the effects of material properties and processing conditions on penetration depth can be easily investigated. Experiments of coating Newtonian glycerin and non‐Newtonian blackstrap molasses onto Toray series carbon paper were conducted to validate developed models. The overall relative error between the predicted and measured penetration depth was found to be typically lower than 20%, which demonstrates the relative accuracy of developed models. Furthermore, based on a parametric study, it was found that the effect of capillary pressure on penetration depth is less than 10% when the ratio of coating bead pressure and capillary pressure is larger than 10. © 2014 American Institute of Chemical Engineers AIChE J 60: 4241–4252, 2014     

Microwave drying process of corns based on double-porous model

Current microwave drying of food product models have generally neglected mass transfer physics, which have resulted in higher predicted temperatures within the food matrix. It is necessary to include mass transfer physics in modeling microwave drying of food products, especially when they are dry for longer durations. In the actual drying process, most of the dry material is a double-porous media formed by the mutual accumulation of porous media, and there is no systematic theory to analyze the drying process of double-porous media. This work presents a new theoretical model based on the ractive pellet bed to achieve the simulation of microwave drying in situation of stacked corns. Compared with the applicable to porous model and analyzed the difference, finally through the change of temperature and moisture was measured by experiments to verify the rationality and accuracy of the double-porous model.     

Synthesis and characterization of low-temperature self-crosslinkable acrylic emulsion for PE film ink

A low-temperature self-crosslinkable acrylic emulsion was synthesized by semi-continuous emulsion polymerization technology using methyl methacrylate (MMA), butyl acrylate (BA), acrylic acid (AA) and diacetone acrylamide (DAAM) as monomers and adipic dihydrazide (ADH) as crosslinker. Transmission electron microscope (TEM) micrograph disclosed spherical emulsion particles possess core–shell structure. Fourier transform infrared (FTIR) spectrogram showed that crosslinking reaction between CO groups of DAAM and NHNH₂ groups of ADH can occur during coating film formation at low temperature, even at room temperature. Differential scanning calorimeter (DSC) analysis indicated that glass transition temperature (Tg) of the crosslinked film is increased by 5 °C. Thermogravimetric analysis (TGA) curves demonstrated that self-crosslinking reaction improves thermal stability of film. As DAAM content increased from 0% to 2%, water absorption ratio of film decreased from 26.2% to 7.4%, adhesion ratio on the PE thin film increased from 0% to 97%. While the n(ADH)/n(DAAM) ratio increased from 0:1 to 0.8:1, crosslinking density of films was increased from 0% to 88%, water absorption ratio decreased from 36.5% to 7.4% and adhesion ratio on the PE thin film increased from 0% to 97%. The optimal DAAM content and n(ADH)/n(DAAM) ratio was 2% and 0.8:1 in this experiment. The emulsion has good potential application in water-based ink for PE film.     

A pore network study of evaporation from the surface of a drying non‐hygroscopic porous medium

The phenomena occurring at the surface of a porous medium during drying in the capillary regime are investigated by pore network simulations. The impact of the formation of wet and dry patches at the surface on the drying rate is studied. The simulations indicate an edge effect characterized by a noticeable variation of saturation in a thin layer adjacent to the porous surface. Also, the results indicate a significant nonlocal equilibrium effect at the surface. The simulation results are exploited to test Schlünder's classical model which offers a simple closure relationship between the evaporation rate and the degree of occupancy of the surface by the liquid. In addition to new insights into the surface phenomena, the results open up new prospects for improving the continuum models of the drying process. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1435–1447, 2018     

二组分液体蒸发模型的理论与实验研究

有毒液体泄漏后的蒸发会导致人员中毒和环境污染,估算有毒液体的蒸发速率对于预测有毒蒸汽在环境中的浓度分布至关重要,尤其是多组分液体,蒸发过程较复杂,蒸发速率的预测大都基于经验模型和半经验模型,且很少考虑热传递对蒸发的影响。文中研究建立了描述二组分液体蒸发质量和液体温度随时间变化的数学模型。设计建造了风洞实验台,并针对不同体积配比下的苯和乙醇混合溶液进行了风洞实验,并将实验测量值同模型计算值进行了比较。结果表明,新建立的模型能够较准确地预测二组分液体蒸发质量和温度随时间的变化,其预测平均偏差分别为25.82%和33.79%,从而为今后研究多组分液体的蒸发过程奠定了基础。     

A model for the evaporation of biomass pyrolysis oil droplets

This paper presents a numerical model for the evaporation and pyrolysis of a single droplet of pyrolysis oil derived from biomass. Continuous thermodynamics theory for multi-component droplet evaporation is used, with the fuel being represented by four fractions: organic acids, aldehydes/ketones, water, and pyrolytic lignin, each of which is described by a separate distribution function. Pyrolysis of the lignin fraction is included, and detailed properties for all fractions are presented. The model is compared with the results of suspended droplet experiments, and is shown to give good predictions of the times of the major events in the lifetime of a droplet.     

Numerical and physical modeling of the permeability of paper to CMC and coating liquids

The penetration of CMC solutions and coating liquids into paper sheets was investigated experimentally and modeled using a Lucas-Washburn equation (Lepoutre, 1978) adequately modified to account for the dynamic contact angle and the coating fluid rheology. A numerical simulation of the fluid penetration based on the finite element resolution of the Navier-Stokes equations was carried out as well. The numerical predictions and the predictions of the Lucas-Washburn equation were compared with the experimental data showing the limitations of the models.     

Solvent evaporation and spray drying technique for micro- and nanospheres/particles preparation: A review

This article presents a comprehensive review of research relating to the preparation of biodegradable and biocompatible controlled/sustained release of micro and nanoparticles. It covers recent developments in the area of technology through solvent evaporation followed by lyophilization and spray drying. The last decade seen a shift from empirical formulation efforts to a technological approach based on better understanding of micro and nanoparticle formation in the solvent evaporation and spray drying technique. This review provides concepts and a theoretical framework for the preparation of micro and nanoparticle formation. Encapsulation of pharmaceutical materials has received much attention due to enhanced effectiveness, bioavailability, and the dissolution rates that can be achieved. Polymeric micro and nanoparticles can be used to transport drug in a rate-controlled and sometimes targeted manner. Initially, laboratory-scale experiments are performed, but for industrial scale-up, experiments are required using sophisticated technologies. The objective of this review article is to summarize the solvent evaporation and spray drying techniques for the preparation of biodegradable and biocompatible controlled/sustained release of micro and nanospheres/particles with focus on the steps involved in its preparation, materials used, and the technique of microencapsulation. The review also summarizes recent research on solvent evaporation and spray drying.     

A comparative study of the interaction between the dried ink layer and PLA film used for packaging purposes

This research aims at comparing the interactions between the water-based printing ink and polylactide (PLA) printing base. As a reference base, a polyethylene terephthalate (PET) film was chosen. The wettability of both films was investigated. The Owens–Wendt method was applied to calculate the surface free energy (SFE). The values of SFE and its polar and dispersive components were compared with the surface tension (ST) of the ink and the polar and dispersive components of ST. The wetting envelopes of the investigated PLA and PET films are presented. Finally, the bonding strength between the dried ink layer and the printing base was analyzed. The PET film exhibited higher values of SFE. However, the bonding strength between the dried ink layer and the printing base was higher for PLA films. Our results reveal that PLA films can be an excellent choice as packaging materials, with comparable or even better print quality than conventional fossil-based plastics.