Recycling and immobilization of zinc extraction residue in clay-based brick manufacturing

1. 65Zn was injected intravenously during transjugular liver biopsy and, from simultaneous hepatic and peripheral venous blood samples, hepatointestinal 65Zn extraction was calculated. Hepatic zinc content was measured in biopsy specimens. 2. On the same occasion samples of liver tissue were taken and their zinc content was measured by atomic absorption spectrophotometry. 3. Seven patients with cirrhosis had significantly lower hepatic zinc content and hepatointestinal zinc extraction than six control patients with mild liver disease. Six patients with chronic hepatitis had a mean hepatointestinal zinc extraction higher than control patients, whereas their mean hepatic zinc content was lower, although the former difference did not achieve statistical significance. 4. These results demonstrate that hepatointestinal extraction of zinc is impaired in cirrhosis, but not in chronic hepatitis.

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Recycling and Extraction of Zinc Ions in Disc-Donut Column Considering Forward Mixing Mass Transfer, Chemical Reaction and Effects of Pulsed and non-Pulsed Condition

10.21203/rs.3.rs-765621/v1 ◽

2021 ◽

Author(s):

Mehdi Asadollahzadeh ◽

Rezvan Torkaman ◽

Meisam Torab-Mostaedi ◽

Mojtaba Saremi

Keyword(s):

Experimental Data ◽

Mass Transfer ◽

Flow Rate ◽

Positive Impact ◽

Plug Flow ◽

Model Parameters ◽

Zinc Ions ◽

Zinc Extraction ◽

Balance Equations ◽

Transfer Rates

Abstract The current study focuses on the recovery of zinc ions by solvent extraction in the pulsed contactor. The Zn(II) ions from chloride solution were extracted into the organic phase containing D2EHPA extractant. The resulting data were characterized for the relative amount of (a) pulsed and no-pulsed condition; and (b) flow rate of both phases. Based on the mass balance equations for the column performance description, numerical computations of mass transfer in a disc-donut column were conducted and validated the experimental data for zinc extraction. Four different models, such as plug flow, backflow, axial dispersion, and forward mixing were evaluated in this study. The results showed that the intensification of the process with the pulsed condition increased and achieved higher mass transfer rates. The forward mixing model findings based on the curve fitting approach validated well with the experimental data. The results showed that an increase in pulsation intensity, as well as the phase flow rates, have a positive impact on the performance of the extractor, whereas the enhancement of flow rate led to the reduction of the described model parameters for adverse phase.

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Hydrometallurgical Process for Zinc Recovery from C.Z.O. Generated by the Steelmaking Industry with Ammonia–Ammonium Chloride Solution

Metals ◽

10.3390/met9010083 ◽

2019 ◽

Vol 9 (1) ◽

pp. 83 ◽

Cited By ~ 5

Author(s):

Shenghai Yang ◽

Duoqiang Zhao ◽

Yafei Jie ◽

Chaobo Tang ◽

Jing He ◽

...

Keyword(s):

Ammonium Chloride ◽

Zinc Dust ◽

Zinc Content ◽

Agitation Speed ◽

Purification Process ◽

Final Solution ◽

Batch Experiments ◽

Zinc Extraction ◽

Zinc Recovery ◽

Second Stage

In this research, some experimental steps were investigated to recover zinc contained in crude zinc oxide (C.Z.O.). In the first stage, the C.Z.O. was treated in NH3–NH4Cl–H2O solution to dissolve the metals. The optimized leaching conditions in batch experiments were obtained: agitation speed 250 rpm, concentration of ammonia and ammonium chloride 2.5 mol/L and 5 mol/L, respectively, time 30min, temperature 40 °C, and L/S = 6 mL/g. The extraction percentage of zinc was over 81% under the optimized leaching conditions. The kinetic study indicates that zinc extraction from the C.Z.O particles was very rapid. In the second stage, the solution from the leaching process was purified by adding zinc dust to the solution. The Cu, Cd, Pb, Sb, and As could be reduced to levels of 0.03, 0.09, 0.87, 0.22, and 0.12 mg/L after the purification process. Finally, the electrowinning process was used to recover dissolved Zn from the final solution. The zinc content in the electrowon zinc was more than 99.99%.

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Removal of magnesium from sphalerite concentrates by means of spent electrolyte deriving from the process of cathode zinc extraction

Gospodarka Surowcami Mineralnymi - Mineral Resources Management ◽

10.2478/v10269-012-0020-4 ◽

2012 ◽

Vol 28 (3) ◽

pp. 43-53

Author(s):

Andrzej Jarosiñski ◽

Adam Kozak ◽

Sylwester Żelazny ◽

Piotr Radomski

Keyword(s):

Zinc Extraction

Streszczenie Występowanie złóż rud cynku i ołowiu w skałach dolomitowych sprawia, że otrzymane koncentraty sfa-lerytowe zawierają domieszkę dolomitu. Praktyka wskazuje, że znaczna część wprowadzanego magnezu z surowcami cynkowymi przechodzi do ostatniej fazy produkcji, elektrolizy cynku. Obecność magnezu w elektrolicie obniża przewodnictwo elektryczne elektrolitu i powoduje pogorszenie wskaźników techniczno-ekonomicznych. Celem opisanych w tym artykule badań było opracowanie metody usuwania magnezu z surowego koncentratu sfalerytowego na drodze chemiczno-flotacyjnej, stosując zużyty elektrolit pochodzący z elektrolizy cynku. Opracowanie ukierunkowano wokół doświadczalnego zobrazowania istniejących zależności i ustalenia optymalnych warunków zaproponowanej procedury. Stopień wyługowania magnezu wynosił około 80%. Straty cynku wynosiły poniżej 2%, natomiast stężenie magnezu w roztworze wynosiło 20%. Z tych roztworów można odzyskiwać magnez i cynk, co będzie przedstawione w następnej publikacji.

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Reactive Zinc Extraction with D2EHPA in a Kühni Miniplant Column

Chemical Engineering & Technology ◽

10.1002/ceat.201800239 ◽

2018 ◽

Vol 41 (11) ◽

pp. 2212-2222

Author(s):

Christian Korb ◽

Alexander Keller ◽

Hans-Jörg Bart

Keyword(s):

Zinc Extraction

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An Influence of EAF Dust Calcining Conditions on Zinc Leaching Efficiency in Ammonium-Chloride Media

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.299.963 ◽

2020 ◽

Vol 299 ◽

pp. 963-967

Author(s):

Yulia I. Toporkova ◽

D.A. Prodanova ◽

O.S. Anisimova

Keyword(s):

Extraction Efficiency ◽

Electric Arc ◽

Arc Furnace ◽

Optimal Conditions ◽

Mass Ratio ◽

Zinc Extraction ◽

Calcination Time ◽

Eaf Dust ◽

Two Stages ◽

Leaching Efficiency

An ammonium leaching of electric arc furnace dust (EAFD) was described in this paper. Ural steelmaking plants obtain EAFD of the following chemical composition, %: 23 Zn; 26 Fe; 10 Cl; 2,5 Ca; 2 Mg; 1,2 Pb; 1 Na. The most complete zinc extraction can be achieved with two-stages treatment by calcination of dusts [1], followed by leaching. The effect of calcination temperature (500-1000 °C), calcination time (1-4 hours) and Ca/Fe mass ratio on zinc extraction efficiency in ammonia solutions was studied. The optimal conditions were proposed to extract up to 87% zinc.

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