Frontispiz: ZIF‐8 Membrane Separation Performance Tuning by Vapor Phase Ligand Treatment

The preparation of Li2CO3 from brine with a high mass ratio of Mg/Li is a worldwide technology problem. Membrane separation is considered as a green and efficient method. In this paper, a comprehensive Li2CO3 preparation process, which involves electrochemical intercalation-deintercalation, nanofiltration, reverse osmosis, evaporation, and precipitation, was constructed. Concretely, the electrochemical intercalation-deintercalation method shows excellent separation performance of lithium and magnesium, and the mass ratio of Mg/Li decreased from the initial 58.5 in the brine to 0.93 in the obtained lithium-containing anolyte. Subsequently, the purification and concentration are performed based on nanofiltration and reverse osmosis technologies, which remove mass magnesium and enrich lithium, respectively. After further evaporation and purification, industrial-grade Li2CO3 can be prepared directly. The direct recovery of lithium from the high Mg/Li brine to the production of Li2CO3 can reach 68.7%, considering that most of the solutions are cycled in the system, the total recovery of lithium will be greater than 85%. In general, this new integrated lithium extraction system provides a new perspective for preparing lithium carbonate from high Mg/Li brine.

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Influence of solvent exchange time on mixed matrix membrane separation performance for CO2/N2 and a kinetic sorption study

Journal of Membrane Science ◽

10.1016/j.memsci.2014.11.008 ◽

2015 ◽

Vol 476 ◽

pp. 590-601 ◽

Cited By ~ 16

Author(s):

Z.A. Jawad ◽

A.L. Ahmad ◽

S.C. Low ◽

T.L. Chew ◽

S.H.S. Zein

Keyword(s):

Membrane Separation ◽

Mixed Matrix Membrane ◽

Separation Performance ◽

Solvent Exchange ◽

Mixed Matrix ◽

Exchange Time ◽

Kinetic Sorption ◽

Sorption Study ◽

Influence Of Solvent

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Effects of Ionic Liquid Blending in Polymeric Membrane: Physical Properties and Performance Evaluation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.625.680 ◽

2014 ◽

Vol 625 ◽

pp. 680-684 ◽

Cited By ~ 2

Author(s):

Dzeti Farhah Mohshim ◽

Hilmi Mukhtar ◽

Zakaria Man

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Membrane Separation ◽

Initial Study ◽

Polymeric Membranes ◽

Polymeric Membrane ◽

Separation Performance ◽

Operating Pressure ◽

Membrane Gas Separation ◽

Pes Membrane

— Polymeric membranes have been extensively used in membrane gas separation process. Nowadays, peoples are modifying the membrane by many ways like coating with ionic liquids to further enhance the membrane separation performance. In this project, ionic liquid modified polymeric membranes (ILMPM) have been successfully developed by blending the ionic liquids with the polymer via solvent evaporation method. The ionic liquid used was 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide, ([emim][Tf2N]) and for comparison purpose, the compositions were varied at 10 and 20 wt/wt%. In general, the blending of [emim][Tf2N] and PES has produced dense membrane with miscible mixture without any phase separation. It was observed that, the CO2permeance of ILMPM has been improved about 271% as compared to the pure PES membrane. However, the CO2permeance decreased with increasing operating pressure, yet the ILMPM CO2permeance still higher than CO2permeance of pure PES membrane. In addition, the CO2/CH4separation performance has greatly increased about 162% as the IL composition is increased. This initial study has proven that IL helps to enhance of CO2permeation and improve selectivity.

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Microfiltration (0·1 μm) of milk: effect of protein size and charge

Journal of Dairy Research ◽

10.1017/s0022029998003008 ◽

1998 ◽

Vol 65 (3) ◽

pp. 443-455 ◽

Cited By ~ 21

Author(s):

OLIVIER LE BERRE ◽

GEORGES DAUFIN

Keyword(s):

Ionic Strength ◽

Ceramic Membrane ◽

Membrane Separation ◽

Soluble Proteins ◽

Separation Performance ◽

Protein Size ◽

Optimal Value ◽

Physicochemical Change ◽

Size Of Particles ◽

The One

Microfiltration (MF) of milk with a ceramic membrane (0·1 μm mean pore diam.) for the separation of casein micelles from soluble proteins was studied. Experiments were performed at constant flux density (J=65 or 75 l h−1 m−2) and wall shear stress (τw=100 or 110 Pa) with milks containing particles and solutes with different sizes and charges, produced by physicochemical change (heat and mechanical treatment, pH, ionic strength, addition of ions). Membrane separation performance was limited by the build up of a cake with characteristics that depended on the size of particles and soluble proteins. Best performance (higher permeability and whey protein transmission) was obtained with milk containing fat on the one hand and calcium phosphate on the other. An optimal value of the particle size was found, close to 0·5–3·0 μm; above this separation performance decreased. In addition, the present study confirmed that the transfer of charged solutes is the consequence of both size and ionic exclusion. Better performance was achieved with higher ionic strength (1 M).

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Mixed Matrix Membrane Performance Prediction for Gas Separation using Modified Models

Journal of Applied Membrane Science & Technology ◽

10.11113/amst.v13i1.86 ◽

2017 ◽

Vol 13 (1) ◽

Author(s):

A. Salimi ◽

O. Bakhtiari ◽

M. K. Moghaddam ◽

T. Mohammadi

Keyword(s):

Gas Separation ◽

Molecular Sieves ◽

Molecular Sieve ◽

Membrane Separation ◽

Maxwell Model ◽

Industrial Applications ◽

Mixed Matrix Membrane ◽

Separation Performance ◽

Mixed Matrix ◽

Two Parameters

Gas separation using membrane processes are potentially economical in industrial scale. Two parameters are used for analyzing the membrane separation performance: permeability and selectivity. There is a trade off between them for polymeric membranes that makes it impossible to increase both of them simultaneously. Molecular sieve membranes, on the other hand, exhibit high permeability and selectivity but are brittle in nature and costly. A new generation of membranes has made many hopes to use simultaneously both desired properties of polymers and molecular sieves in a structure called “mixed matrix membrane (MMM)” where a molecular sieve is incorporated within a polymer matrix. As other branches of science and engineering, having a tool to predict MMMs performance seems to be essential to save time and money for research and industrial applications. Many mathematical models were developed to predict MMMs performance based on separation performance of fillers and polymers. Maxwell model is the simplest model developed for prediction of electrical properties of composite materials but it is not perfect for all cases. Some modifications were performed on Maxwell model and some other modified models were developed for better prediction of MMMs separation performance. In this research, modified Maxwell and Bruggeman models were employed to predict gas separation performance of some MMMs in the current work and the results were acceptable for all non–ideal cases which might be occurred in MMMs structure.

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Applications and characterization of silicalite-1/polydimethylsiloxane composite membranes for the pervaporation of a model solution and fermentation broth

Journal of Polymer Engineering ◽

10.1515/polyeng-2018-0138 ◽

2019 ◽

Vol 39 (2) ◽

pp. 152-160

Author(s):

Sutida Marthosa ◽

Wirote Youravong ◽

Chaiwat Kongmanklang ◽

Watsa Khongnakorn

Keyword(s):

Separation Factor ◽

Membrane Separation ◽

Fermentation Broth ◽

Composite Membranes ◽

Decomposition Temperature ◽

Ethanol Solution ◽

Pdms Membrane ◽

Separation Performance ◽

Gravimetric Analysis ◽

Initial Decomposition Temperature

AbstractEthanol recovery via pervaporation is greatly influenced by membrane separation performance, which can be enhanced by adding hydrophobic fillers such as silicalite-1. Silicalite-1 was prepared by controlling the gel molar composition in hydrothermal synthesis, and it was incorporated into a polydimethylsiloxane (PDMS) membrane on Teflon. The silicalite-1 Si-O-Si structures interacted with the -Si(CH3)2-O- backbone of the PDMS chain. The thermal gravimetric analysis results showed that the silicalite-1 improved the thermal stability and raised the initial decomposition temperature from 405°C to 450–470°C. Increasing silicalite-1 content from 5 to 20 wt% enhanced the relative ethanol/water swelling from 1.33% to 1.52% and advanced the contact angle from 112.6° to 138.6°. Addition of 20 wt% silicalite-1 improved the separation factor in broth from 2.55 to 5.56. When using 20 wt% silicalite-1/PDMS membrane and replacing the ethanol solution with broth, fouling reduced the flux from 597 to 482 g m−2h−1, but the broth composite increased the separation factor from 3.14 to 5.56. The overall pervaporation separation index with a santol broth of the 20 wt% silicalite-1/PDMS and commercial PDMS membranes were 2199 and 2110. The prepared membranes had similar overall performance as a commercial membrane.

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A new strategy for membrane-based direct air capture

Polymer Journal ◽

10.1038/s41428-020-00429-z ◽

2020 ◽

Vol 53 (1) ◽

pp. 111-119

Author(s):

Shigenori Fujikawa ◽

Roman Selyanchyn ◽

Toyoki Kunitake

Keyword(s):

Membrane Separation ◽

New Technology ◽

Chemical Processes ◽

Organic Polymer ◽

Separation Performance ◽

Separation Membranes ◽

Direct Air Capture ◽

New Strategy ◽

Air Capture ◽

And Performance

AbstractDirect CO2 capture from the air, so-called direct air capture (DAC), has become inevitable to reduce the concentration of CO2 in the atmosphere. Current DAC technologies consider only sorbent-based systems. Recently, there have been reports that show ultrahigh CO2 permeances in gas separation membranes and thus membrane separation could be a potential new technology for DAC in addition to sorbent-based CO2 capture. The simulation of chemical processes has been well established and is commonly used for the development and performance assessment of industrial chemical processes. These simulations offer a credible assessment of the feasibility of membrane-based DAC (m-DAC). In this paper, we discuss the potential of m-DAC considering the state-of-the-art performance of organic polymer membranes. The multistage membrane separation process was employed in process simulation to estimate the energy requirements for m-DAC. Based on the analysis, we propose the target membrane separation performance required for m-DAC with competitive energy expenses. Finally, we discuss the direction of future membrane development for DAC.

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