scholarly journals Hydrometallurgical Technology for Processing of Galvanic Sludges

2020 ◽  
Author(s):  
O.Yu. Makovskaya ◽  
K.S. Kostromin
Keyword(s):  
Sulfuric Acid ◽  
Exchange Resin ◽  
Ion Exchange Resin ◽  
Nickel Ion ◽  
Disposal Area ◽  
Nickel Recovery ◽  
Sorption Concentration ◽  
Ferrous Metals ◽  
Galvanic Sludge ◽  
Non Ferrous Metals

The problem of processing galvanic sludges, formed as a result of neutralization of technological solutions and wastewater containing heavy non-ferrous metals is considered in this study. At present, sludges are transported to disposal area and are not used in any way. Typically, such sludges contain significant amounts of chromium and nickel, which creates environmental hazard. Investigated sludge contains up to 6,6% Ni and up to 7,4% Cr. The hydrometallurgical process to treatment of these sludges is carried out. Solutions of sulfuric acid and ammonia were used as lixiviants. It is shown that when using a solution of sulfuric acid with pH=1,5, extraction of up to 93,3% Cu, 70,2 Ni, 90,3 Zn is achieved. For selective nickel recovery sorption concentration by Lewatit TP207 is proposed. Keywords: Galvanic sludge, hydrometallurgy leaching, nickel, ion-exchange resin

Leaching of Non-Ferrous Metals from Galvanic Sludges

2019 ◽  
Vol 946 ◽  
pp. 591-595 ◽  
Author(s):  
O.Yu. Makovskaya ◽  
K.S. Kostromin
Keyword(s):  
Sulfuric Acid ◽  
Environmental Hazard ◽  
Hydrometallurgical Process ◽  
Disposal Area ◽  
Ferrous Metals ◽  
Galvanic Production ◽  
Non Ferrous Metals

The problem of processing slimes of galvanic production, formed as a result of neutralization of technological solutions and wastewater containing heavy non-ferrous metals is considered. At present, sludges are transported to disposal area and are not used in any way. Typically, such sludges contain significant amounts of chromium and nickel, which creates environmental hazard. Investigated sludge of Dimitrovgrad Automobile Units Plant (Russia) contains up to 6.6% Ni and up to 7,4% Cr. The hydrometallurgical process is proposed to treatment of these sludges. Solutions of sulfuric acid, ammoniaс chloride and Trilon B were used as lixiviants. It is shown that when using a solution of sulfuric acid with pH=1,5, extraction of up to 93,3% Cu, 70,2 Ni, 90,3 Zn is achieved.

scholarly journals Reaction of Nickel Ion Fixed on the Ion Exchange Resin with 2-Thenoyltrifluoroacetone

1975 ◽  
Vol 48 (10) ◽  
pp. 2829-2831 ◽  
Author(s):  
Kunio Ohzeki ◽  
Tooru Tamura ◽  
Tomihito Kambara
Keyword(s):  
Ion Exchange ◽  
Exchange Resin ◽  
Ion Exchange Resin ◽  
Nickel Ion

Selective Acid Leaching of Copper and Zinc from Old Flotation Tailings

2020 ◽  
Vol 989 ◽  
pp. 554-558
Author(s):  
Aleksandr Bulaev ◽  
Vitaliy Melamud
Keyword(s):  
Sulfuric Acid ◽  
Acid Leaching ◽  
Distilled Water ◽  
Acid Solutions ◽  
Iron Ions ◽  
Flotation Tailings ◽  
Ferrous Metals ◽  
Non Ferrous Metals ◽  
Sulfuric Acid Solutions ◽  
Cu And Zn

The goal of the present work was to develop hydrometallurgical method based on acid leaching, which makes it possible to perform selective extraction of non-ferrous metals from old flotation tailings. Leaching was performed with sulfuric acid solutions (from 0.5 to 10%) and distilled water. Leaching was carried out using percolators and bottle agitator. Percolators were loaded with 100 g of old tailings, and leaching was performed with 100 mL of acid solutions. Pulp density during agitation leaching (S: L) was 1: 5. Two samples of old flotation samples were studied. The first sample of flotation tailings contained 0.26% of copper, 0.22% of zinc, and 17.4% of iron; while the second sample contained 0.36% of copper, 0.23% of zinc, and 23.2% of iron. Percolation leaching made it possible to extract up to 43 and 47% of Cu and Zn from the first sample. Extraction rate was maximum during the leaching with 1 and 2.5% sulfuric acid solutions. During the agitation leaching, the maximum extraction rate was reached with a 2.5% sulfuric acid solution (52 and 54% Cu and Zn), but the leaching rate with all solutions and distilled water differed insignificantly. Percolation leaching made it possible to extract up to 54 and 37% of Cu and Zn from the second sample of tailings, while agitation leaching made it possible to extract up to 34 and 68% Cu and Zn, respectively. The rate of non-ferrous metals extraction from the second sample with water did not differ significantly from that of obtained in the experiments with sulfuric acid solutions. In all experiments, the increase in the H2SO4 concentration led to the increase in concentrations of iron ions in productive solutions, which impedes the extraction of non-ferrous metals from solutions. Thus, it was possible to reach selective leaching of non-ferrous metals and to obtain solutions with relatively low concentrations of iron ions.

scholarly journals Hemicellulose-derived sugars solubilisation of rape straw. Cofermentation of pentoses and hexoses by Escherichia coli

2015 ◽  
Vol 13 (3) ◽  
pp. e0213 ◽  
Author(s):  
Juan Carlos López-Linares ◽  
Cristóbal Cara-Corpas ◽  
Encarnación Ruiz-Ramos ◽  
Manuel Moya-Vilar ◽  
Eulogio Castro-Galiano ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Sulfuric Acid ◽  
Ion Exchange ◽  
Acid Concentration ◽  
Exchange Resin ◽  
Ethanol Yield ◽  
Ion Exchange Resin ◽  
Mild Conditions ◽  
Rape Straw ◽  
Hemicellulosic Sugars

<p>Bioconversion of hemicellulose sugars is essential for increasing fuel ethanol yields from lignocellulosic biomass. We report for the first time with rape straw, bioethanol production from hemicellulose sugars. Rape straw was pretreated at mild conditions with sulfuric acid to solubilize the hemicellulose fraction. This pretreatment allows obtaining a prehydrolysate, consisting basically in a solution of monomeric hemicellulosic sugars, with low inhibitor concentrations. The remaining water insoluble solid constitutes a cellulose-enriched, free of extractives material. The influence of temperature (120ºC and 130ºC), acid concentration (2-4% w/v) and pretreatment time (30-180 min) on hemicellulose-derived sugars solubilisation was evaluated. The highest hemicellulosic sugars recovery, 72.3%, was achieved at 130ºC with 2% sulfuric acid and 60 min. At these conditions, a concentrated sugars solution, 52.4 g/L, was obtained after three acid consecutive contacts, with 67% xylose and acetic acid concentration above 4.5 g/L. After a detoxification step by activated charcoal or ion-exchange resin, prehydrolysate was fermented by ethanologenic <em>Escherichia coli</em>. An alcoholic solution of 25 g/L and 86% of theoretical ethanol yield was attained after 144 h when the prehydrolysate was detoxified by ion-exchange resin. The results obtained in the present work show sulfuric acid pretreatment under mild conditions and <em>E. coli</em> as an interesting process to exploit hemicellulosic sugars in rape straw.</p>

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