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Vanadium removal from spent sulfuric acid plant catalyst using citric acid and Acidithiobacillus thiooxidans

Mikoda Bartosz, Potysz Anna, Kucha Harry, Kmiecik Ewa

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 4

514--527

EN

Spent catalysts being considered hazardous wastes exhibit a high metal content in mobile forms. In addition, growing demand for circular economy policy applications requires proper utilization of these wastes. This study aimed at the assessment of vanadium leaching from spent desulfurization catalyst derived from sulfuric acid plant dump located nearby a copper smelter. Chemical and phase composition of the catalyst has been characterized. The extraction has been performed using chemical (0.1-M and 1-M citric acid) and biological (biotic solution with Acidithiobacillus thiooxidans) methods, using different experimental parameters (pulp density, particle size, leaching time) to observe V leaching behavior and kinetics. The results revealed that both citric acid and bacteria carried out the extraction process well. The optimal parameters for acid leaching were < 0.2-mm particle size and 2% pulp density, which allowed to leach out 95% of V from spent catalyst within 48 h. The bacterially mediated extraction resulted in 93% V leached out within 21 days with 2% pulp density. The experiments showed that V present in the catalyst is susceptible to bioleaching and organic acid leaching with the latter being a quicker process.

2

Surface properties of neutral components in copper column bioleaching of black shale samples

Sadowski Z., Baranska J., Pawlowska A.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 4

1146--1151

EN

The behaviour of glass beads and polyethylene pellets as the extra bacteria support in the fine black shale ore in the column bed bioreactor was compared. Capillary rise experiments enabled the calculation of the contact angle and the surface free energy of glass beads and polyethylene pellets. The results showed that the support material made up of polyethylene pellets yielded a higher copper extraction, which could be explained by conditions favourable to cell adhesion on the polyethylene surface.

3

Waste solder and printed circuit board: the emerging secondary sources for recovery of metals

Jadhav U. U., Hocheng H.

Archives of Materials Science and Engineering

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2015

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Vol. 72, nr 1

5--15

EN

Purpose: Purpose: The goal of the paper is to focus on waste solder and printed circuit board: the emerging secondary sources for recovery of metals. Design/methodology/approach: The worldwide reserves of high-grade ores are diminishing. At the same time the demand for heavy metals is ever increasing with the progress of the industrialized world. The rapid progress of electronic packaging technology is resulting in huge amounts of electronic waste (E-Waste) particularly in the form of solders and printed circuit boards (PCBs). Such E-waste contains various metals. The waste solders and PCB can act as large stockpiles of metals. Hence, they can be important secondary sources of valuable metals. Thus recycling of waste solders and PCB is not only useful for resource recovery from waste materials, but also for the protection of the environment. Findings: Comparing with the pyrometallurgical processing, hydrometallurgical method is more exact, more predictable, and more easily controlled. Bio-hydrometallurgical processes are emerging as potential environmentally friendly approaches. Research limitations/implications: Several promising metal recovery processes were developed to recover the precious metals from E-waste. There is a need to fill the gap areas in achieving a cleaner and economical recycling process. Also more studies are needed in the area of metal separation and recovery from PCB leach liquor. Orginality/Value: This review article will provide a concise overview of current disposal and recycling operations. Keywords: Electronic waste; Solder; Printed circuit board; Metal recovery; Pyrometallurgy, Hydrometallurgy; Bio-hydrometallurgy.

4

Extraction of metals from electronic waste by bacterial leaching

Willner J., Fornalczyk A.

Environment Protection Engineering

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2013

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Vol. 39, nr 1

197--208

EN

Electronic waste is usually processed by means of classical methods, i.e. in pyro- and hydro-metallurgical processes. However, new solutions for more economically and ecologically efficient recovery of metals are constantly being searched for. Biohydrometallurgy can become a promising technology of recovering metals from industrial waste. Bioleaching - one of the methods applied in that technology - is the subject of particular interest of many scientific centres. The paper presents the results of laboratory tests of bacterial leaching of metals from electronic scrap. It describes the mechanisms of this process and the factors influencing the chemical reaction. The paper also presents preliminary results of experimental studies on the copper bioleaching from electronic waste with the participation of Acidithiobacillus ferrooxidans bacteria.

5

Biohydrometalurgia - alternatywa dla procesów metalurgicznych

Gajda B., Bogacki M.B.

Rudy i Metale Nieżelazne

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2012

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R. 57, nr 11

778-784

PL

Biohydrometalurgia z początkiem XXI wieku nabiera coraz większego znaczenia jako nisko kosztowa, stosunkowo łatwa do zastosowania oraz umożliwiająca przetwarzanie bardzo ubogich surowców, zarówno naturalnych jak też odpadów, technologia. O szybkim jej rozwoju świadczyć może fakt, iż w 2006 r. ponad 2 mln t miedzi rocznie powstawało w zakładach wykorzystujących bioługowanie. Technologia ta wykorzystywana jest nie tylko w zakładach metalurgicznych do otrzymywania miedzi, niklu, kobaltu, cynku, złota czy uranu, ale również do przetwarzania odpadów, między innymi osadów powstających w oczyszczalniach ścieków. W prezentowanej pracy przeglądowej omówiono dwa podstawowe mechanizmy bioługowania siarczkowych rud metali: mechanizm bezpośredni oraz pośredni. Następnie przeprowadzono przegląd podstawowych procesów bioługowania zastosowanych do przetwarzania rudy miedzi, niklu i kobaltu, cynku i złota.

EN

Biohydrometallurgy the beginning of the twenty-first century is becoming increasingly important as a low-cost, relatively easy to use and allows processing of very poor resources, both natural as well as waste technology. The rapid development of evidenced by the fact that in 2006, more than 2 million tons of copper per year arose in plants using bioleaching. This technology is used not only in the metallurgical plants for the preparation of copper, nickel, cobalt, zinc, gold and uranium, but also for the processing of waste, including sludge generated in wastewater treatment plants. In the present review, we discuss two basic mechanisms of bioleaching of sulphide ores: mechanism of direct and indirect. This was followed by an overview of the basic processes used in the bioleaching process copper ore, nickel and cobalt, zinc and gold.