Recovery of magnesium by membrane crystallization with ion-exchange hollow-fibres

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F28676092%3A_____%2F19%3AN0000096" target="_blank" >RIV/28676092:_____/19:N0000096 - isvavai.cz</a>

Výsledek na webu

<a href="http://www.czemp.cz/cs/workshop-students-presentation-fulltexts/wsp-2019-fulltexty" target="_blank" >http://www.czemp.cz/cs/workshop-students-presentation-fulltexts/wsp-2019-fulltexty</a>

DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Recovery of magnesium by membrane crystallization with ion-exchange hollow-fibres

Popis výsledku v původním jazyce

Most of desalination plants are based on reverse osmosis process, which produces drinking water and concentrated solution of various salts. Brine disposal is linked with environmental difficulties. If extraction of minerals dissolved in these solutions in valuable form was possible, not only environmental cost for their disposal could decrease, but so financial cost could decrease. One of options how to achieve this is membrane crystallization. In this study, such promising process was applied in experiments to obtain Mg(OH)2 from solutions of MgCl2 and NaOH, flowing on the opposite sides of the anion-exchange hollow-fibres. Expected advantages of membrane crystallization have been confirmed. Conversion and formation density of product in hollow-fibres highly exceeded possibilities of flat-sheet ion-exchange membranes. Another set of experiments confirmed better control over the crystallization process by modifying the flow rates and the concentrations of used solutions. To evaluate feasibility of this process in desalination plants, artificial brine solutions have been prepared and used as source of Mg2+ – purity of crystals obtained from brine solutions were different, depending on the brine solution composition. Brine with low amount of Ca2+ proved to be more usable, with purity of synthesised crystals above 98.6%, which confirms high economic potential of process, as the price per ton of Mg(OH)2 highly depends on its purity. The most significant drawback of this process is formation of crystals on the hollow-fibres surface – in the experiments glass beads were used as abrasive, with partial success. The amount of Mg(OH)2 in the solution was 1.5 times higher than in experiments without the glass beads.

Název v anglickém jazyce

Recovery of magnesium by membrane crystallization with ion-exchange hollow-fibres

Popis výsledku anglicky

Most of desalination plants are based on reverse osmosis process, which produces drinking water and concentrated solution of various salts. Brine disposal is linked with environmental difficulties. If extraction of minerals dissolved in these solutions in valuable form was possible, not only environmental cost for their disposal could decrease, but so financial cost could decrease. One of options how to achieve this is membrane crystallization. In this study, such promising process was applied in experiments to obtain Mg(OH)2 from solutions of MgCl2 and NaOH, flowing on the opposite sides of the anion-exchange hollow-fibres. Expected advantages of membrane crystallization have been confirmed. Conversion and formation density of product in hollow-fibres highly exceeded possibilities of flat-sheet ion-exchange membranes. Another set of experiments confirmed better control over the crystallization process by modifying the flow rates and the concentrations of used solutions. To evaluate feasibility of this process in desalination plants, artificial brine solutions have been prepared and used as source of Mg2+ – purity of crystals obtained from brine solutions were different, depending on the brine solution composition. Brine with low amount of Ca2+ proved to be more usable, with purity of synthesised crystals above 98.6%, which confirms high economic potential of process, as the price per ton of Mg(OH)2 highly depends on its purity. The most significant drawback of this process is formation of crystals on the hollow-fibres surface – in the experiments glass beads were used as abrasive, with partial success. The amount of Mg(OH)2 in the solution was 1.5 times higher than in experiments without the glass beads.

Druh

D - Stať ve sborníku

CEP obor

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OECD FORD obor

20402 - Chemical process engineering

Projekt

<a href="/cs/project/LO1418" target="_blank" >LO1418: Progresivní rozvoj Membránového inovačního centra</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Workshop of Students´ Presentations 2019

ISBN

978-80-906831-9-8

ISSN

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e-ISSN

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Počet stran výsledku

2

Strana od-do

12-13

Název nakladatele

Czech Membrane Platform

Místo vydání

Česká Lípa

Místo konání akce

Stráž pod Ralskem

Datum konání akce

16. 10. 2020

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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