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High Concentration of Arsenic Removal from Acid Leaching Solution of Zinc Oxide Dust by Water-Quenched Slag

Sun H. Y., Sen W., Kong X., Liu G. Y.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 1

425--430

EN

The present work provides a study on high concentration of arsenic removal from acid leaching solution of zinc oxide dust by water-quenched slag. The water-quenched slag is a waste slag produced from fuming furnace of lead pyrometallurgical process and used as a substitute of ferrous sulfate heptahydrate to precipitate arsenic at purification section. The effects of reaction temperature, reaction time, the addition of H2O2 and the addition of water-quenched slag on arsenic removal rate were systematically investigated. The reaction temperature of 70°C, reaction time of 1h, H2O2 addition of 10.8 mL/L and water-quenched slag addition of 17.8 g/L are identified as the best technical parameters. At the optimum conditions, the arsenic (III) with high concentration (As 4.13 g/L) is efficiently removed (arsenic removal rate > 99%). The filtrate (Fe 1.21 mg/L, As 1.53 mg/L) with low concentrations of arsenic and iron and the stable filter residue are also obtained successfully. The United States EPA Toxicity Characteristic Leaching Procedure (TCLP) test shows that the As leachability never exceeds the regulatory limit of 5 mg/L As. The results suggest that the water-quenched slag shows potential for removing high concentration of arsenic from acid leaching solution of zinc oxide dust.

2

Zastosowanie koagulantów żelazowych do usuwania arsenu z wód podziemnych w procesie koagulacji powierzchniowej

Bray R.

Technologia Wody

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2013

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Nr 5 (25)

26-290

PL

W pracy przedstawiono wyniki badań w skali ułamkowo technicznej nad zastosowaniem koagulantów żelazowych do usuwania arsenu z wody podziemnej. Stężenie arsenu w ujmowanej wodzie podczas badań sięgało 36 (ag/l i niemal czterokrotnie przekraczało wartość dopuszczalną dla wód przeznaczonych do spożycia (<10 |J.g/l). Proces polegał na dozowaniu koagulantu żelazowego, napowietrzaniu wody a następnie filtracji przez dwuwarstwowe złoże kwarcowo-piroluzytowe. Badania wykazały, że już przy dawkach koagulantu PIX 112 rzędu 2,0 mg Fe/l uzyskiwano obniżenie stężenia arsenu o niemal 80% (7,6 ?ig/l), do poziomu poniżej dopuszczalnej normy. Dalszy wzrost stężenia koagulantu powodował już tylko nieznaczną poprawę skuteczności procesu. Stężenie żelaza po filtracji było śladowe. Dzięki zastosowaniu w złożu filtracyjnym warstwy piroluzytu, z wody usuwany był również mangan.

EN

The aim of the study was to analyze the efficiency of arsenic removal from groundwater using iron coagulants. In tested groundwater arsenic concentration was equal 36 pg/1 and four times exceeded the limit value for water intended for human consumption (<10 (j.g/1). The experiments were carried out in pilot-plant scale and consisted of iron coagulant dosing, aeration and next filtration of treated groundwater through double-layered quartz- pyrolusite bed. According to the obtained results, dosages of PIX 112 reaching 2.0 mg Fe/1 caused the reduction of arsenic up to 80% (7.6 |ig/l), to the level accepted for human consumption (<10 |ig/l). Further increase in the concentration of coagulant resulted only in a slight improvement of the process efficiency. The iron concentration after filtration was at the trace level. Filtration through double-layered quartz- pyrolusite bed caused additionally the removal of manganese from treated groundwater.

3

Sorption properties of fly ash from brown coal burning towards arsenic removal

Polowczyk I., Bastrzyk A., Sawiński W., Koźlecki T., Rudnicki P., Sadowski Z.

Czasopismo Techniczne. Chemia

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2011

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R. 108, z. 1-Ch

135-142

EN

In the present work, the sorptive capacity of fly ash from the combustion of brown coal in relation to arsenic(III) removal from the standard solution as well as the potential application of fly ash in actual wastewater purification have been evaluated.

PL

W tym artykule zbadano pojemność sorpcyjną popiołów lotnych powstających podczas spalania węgla brunatnego w stosunku do arsenu(III) usuwanego z roztworu standardowego oraz zbadano możliwość zastosowania popiołów w oczyszczaniu ścieku rzeczywistego.

4

Extractive removal of arsenic from sulphuric acid solutions

Wiśniewski M., Iberhan L.

Polish Journal of Chemical Technology

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2004

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Vol. 6, nr 3

41-44

EN

In the study, the extraction of arsenic(III) and arsenic(V) was investigated from the concentrated aqueous solutions of the sulphuric acid using the hydrophobic reagents of various structure and composition. The studies included stripping with water, too. The studies took advantage of the organophosphorus extracting agents CyanexŽ 923, CyanexŽ 925, CyanexŽ 301 and their mixtures, as well as of the 2-ethylhexane-l,3-diol and the hydroxamic acids dissolved in toluene. The study aimed at the removal of the maximum amounts of arsenic(III) and arsenic(V) from the sulphuric acid solution at the concentration of 150 g/dm3, using the multistage co-current or the counter-current extraction and, then, the removal of the arsenic from the organic phases by stripping with the water, with the regeneration of the extracting agent. The linear extraction and the stripping isotherms obtained in a given range of the concentrations, were used for a discussion on the multistage extraction, and the stripping of arsenic. The experimental results proved to be consistent with the obtained isotherms of the two processes and their equations.