2 edition of Suphuric acid leaching of clays for the production of alumina ... found in the catalog.
Suphuric acid leaching of clays for the production of alumina ...
Howard Calvin Parkman
Written in English
|The Physical Object|
|Pagination||, 67 leaves,|
|Number of Pages||67|
Abstract. Hydrochloric (HCl) acid is commonly used to acidize sandstone formations. Although much emphasis has been placed upon the dissolution and reprecipitation theories for acidization with hydrofluoric (HF) acid, little information is available concerning the effect of HCl acid on clay minerals commonly found in sandstone formations. mixture at high temperature before acid-leaching reaction. BAI et al  also boosted the alumina extraction efficiency by sintering the mixture of coal fly ash and concentrated sulfuric acid at °C to transform most of aluminum in coal fly ash into aluminum sulfate, which can be extracted out from coal fly ash by hot water.
The objective of this PhD research was to investigate the leaching of acid clays with acid mine/rock drainages (AMD/ARD) typically found in U.S. soils and develop information supporting the phenomena of the release of elevated concentrations of aluminum from such interactions. but the solubility of the alumina in the alkaline solution was less than that of the silica at any specific contact time studie d. Keywords: kaolinitic clay, silica, leaching, extraction, alkali. INTRODUCTION The total annual production of high alumina cement is a very .
Approx. 20 % of worlds copper production are gained by hydrometallurgical leaching processes, mainly by heap leaching with sulfuric acid and subsequent solvent extraction (SX) and electro winning (EW) treatment. Typical ore heaps in heap leaching are 4 - 12 m high and have a . Postprint of R.M. Rivera, G. Ounoughene, C.R. Borra, K. Binnemans, T. Van Gerven (). Neutralisation of bauxite residue by carbon dioxide prior to acidic leaching for metal recovery. Minerals Engineering , 92– 2 33 1. Introduction 34 Bauxite residue (red mud) is the waste product generated during alumina production by the BayerFile Size: KB.
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Used to prepare alumina; standard sulfuric acid processing and leaching via an intermediate product. To prepare the alumina by standard sulfuric acid leaching, the clay sample was calcined in air at oC to oC with a heating interval of oC. The duration of calcination was varied from 30 min to min.
Extraction of Alumina from Local Clays by Hydrochloric Acid Process 31 period and temperature of extraction. The production of a crude alumina from clay was also investigated on a pilot plant scale. Weston described in several patents the production of a purified alumina-silica.
abundant in Saudi Arabia for the production of pure alumina by calcination at oC for 1hr then leached by hydrochloric acid. The effects of leaching temperature (25oC to boiling temperature), period of activation ( minutes), acid concentration (1M – 6M), File Size: KB. The most promising of several acid processes investigated appears to be HCl leaching of the clay followed by crystallization of AlCl36H20 by sparging with HCl gas.
To obtain Al2O3 by this process, calcined clay is leached with pct-HCl, a solid-liquid separation is made, and the liquor is treated by solvent extraction to remove iron.
The influence of hydrochloric acid concentration on alumina transition in solution was shown. Determined the apparent degree of the process on reagents. The obtained results allow to allocate 3 limiting stages of the process: – °C — a chemical reaction (E a = kJ/mol), – °C — intermediate region (E a = kJ Author: Dmitry Valeev, Vyacheslav Pak, Alexandra Mikhailova, Margarita Gol’Dberg, Mark Zheleznyi, Irina Doro.
Introduction. Between –, the of Mines assessed various processes to produce alumina from non-bauxitic ores (Bengtson,Habashi, ).The sulphuric and hydrochloric acid leaching processes were brought to pilot plant evaluation (Cohen et al.,Bengtson,Sawyer et al., ) while the other studied processes remained at the laboratory by: In the production of alumina (Al2O3) from clays by acid leaching, thermal activation by calcination is applied widely as a pre-treatment to improve the dissolution of aluminum.
Installation costs for the two systems will be about the same, except that, where an ore requires more than 1½ lb.
of acid per pound of copper produced, the additional costs of an acid plant plus railroad equipment for carrying it when produced at a distance from the leaching plant, plus storage tanks, piping, etc., at the leaching plant, must. The acid leaching of aluminium from several non traditional ores, bayerite, kaolinite, different clays, coal mining wastes and coal fly ashes, and the kinetic of their dissolution are described.
The effects of time, temperature, acid concentration, sample calcination, particle size were by: 4. Heterotrophic, acid-producing bacteria and fungi were used to leach aluminum from clays. The best results were achieved by means of a strain of Aspergillus niger, which formed oxalic and citric.
LEACHING ALUMINUM FROM CALCINED KAOLINITIC CLAY WITH NITRIC ACID By Richard S. Olsen, 1 William G. Gruzensky,2 Sophie J. Bullard,3 R. Beyer, 1 and Jack L. Henry 4 ABSTRACT Prior work by the Bureau of Mines demonstrated a feed preparation method that eliminates the formation of slime during leaching of cal.
Other articles where Acid leaching is discussed: uranium processing: Leaching: Acid leaching is commonly performed by agitating an ore-leach mixture for 4 to as long as 48 hours at ambient temperature.
Except in special circumstances, sulfuric acid is the leachant used; it is supplied in amounts sufficient to obtain a final leach liquor at about. Nano size α-alumina powder was successfully prepared from calcined kaolin by the acid leaching process.
Washing was a crucial step for removing halide which was an obvious product along with the desired aluminium hydroxide. Corundum phase first appeared at Cited by: The Bureau of Mines evaluated a sulfurous acid-sulfuric acid process for recovering alumina from clay, in which clay is leached successively with sulfurous acid and sulfuric acid.
The resulting aluminum sulfite and aluminum sulfate solutions are combined and heated to produce a. Srećko Stopić et al.: Sulphuric Acid Leaching of the Serbian Nickel Lateritic Ore Laterites are oxide ores widely distributed in the equatori-al regions.
Lateritic deposits usually consist of three layers, namely the limonitic, the saprolitic and garnieritic layer. It is known that 54 File Size: KB. Alumina monohydrate is produced by leaching calcined clay and subjecting the leach liquor to pressure hydrolysis wherein the vapor and heating resulting from the pressure hydrolysis are directly utilized for leaching of calcined clay.
The aluminum monohydrate may be roasted to yield alumina. The leaching kinetics of calcined magnesite by using acetic acid solutions was investigated in a batch reactor by using the parameters such as temperature, acid concentration and particle size.
Recovery of Alumina from Khushab Bauxite by Leaching with Sulphuric Acid and Removal of Iron Impurity by Ethanol August Journal- Chemical Society of Pakistan 36(4) valent iron ion in the leaching solution a er acid leaching process.
e detailed information of the experiments could be found in previous studies [, ]. Results and Discussions e e ect of leaching time on the kinetic study of the extraction of Al 2 O 3 and Fe 2 O 3 using the hydrochloric acid solution is shown in Table.
e relationship curve Cited by: 3. have identified calcinations temperature, leaching temperature, acid concentration, liquidsolid ratio and stirrin- g speed to be very important process parameters that affects the leaching of minerals from clays.
In the process optimization of sulphuric acid leaching of alumina from Nteje clay. Optimised acid leaching and liquor purifi cation processes have been established for synthetic DSP, lime-free BR and lime containing BR using sulphuric acid without troublesome leaching of silica.
A soda extraction extent of up to 80% was achieved by stoichiometric consumption of sulphuric acid to form sodium sulphate with DSP or lime-free BR.Bauxite residue, as solid waste from alumina production, contains mainly hematite [Fe2O3].
Kinetic study of iron leaching of bauxite residue by diluted sulfuric acid at atmospheric pressure has.Leaching is a process widely used in extractive metallurgy where ore is treated with chemicals to convert the valuable metals within into soluble salts while impurity remain can then be washed out and processed to give the pure metal; the material left over is commonly referred to as ed to pyrometallurgy leaching is easier to perform, requires less energy and is.