RU2001134C1 - Burnt pyrites complex reprocessing method - Google Patents

Abstract

Usage: chemical technology, sulfuric acid production for the disposal of solid waste. The essence of the pyrite cinder from the burning of pyrites is leached with weakly acidic aqueous solutions, blister copper is isolated by cementation after adding iron scrap to achieve O.P. 0-80 mV. in the solution of copper cementation, the oxidizing agent is dosed to an ATS value in the solution of 370 mV, then, maintaining the value of О В P. at this level, the alkaline reagent is dosed until a pH of 3.5 is reached, after which the solution is separated from the formed mouse containing sediment and raised therein the ORP value is up to 600 mV and is directed sequentially to the deposition of iron hydroxide, from which, after heat treatment, iron oxide pigment and zinc carbonate are obtained, and the precipitate is combined with cinder tail pulp after extraction of useful components and sent kladirovanie. 1 tab

Description

The invention relates to chemical technology and can be used in enterprises producing sulfuric acid from pyrites.

The process of producing sulfuric acid from pyrites is accompanied by the production of significant amounts of pyrite cinder as waste. Along with iron, the content of which is 50-55% {BEFORE: zinc, copper, gold, silver. Holdings, allowing to consider the cinder as a promising source of non-ferrous and noble metals.

A known hydrometallurgical method for the extraction of non-ferrous metals, in particular cobalt, nickel from metal-containing substances, such as mattes, including processing raw materials with aqueous solutions containing ammonium sulfate, sodium sulfate, nickel sulfate and free sulfuric acid, providing a pH value in the solution of 3.0-4.5, separation of the undissolved precipitate containing precious metals and the subsequent recovery of precious metals.

The disadvantage of this method is the use of a significant number of reagents for dissolving non-ferrous metals and the complexity of the scheme for their separation from solution.

There is also known a method of extracting zinc and copper from a pyrite cinder by treating it with an aqueous ammonia solution in two stages with a ratio of solid and liquid phases (T: G) 1: (15-20). in the first stage, a solution containing 3-7% ammonia and 0.02-0.05% ammonium sulfide, and in the second stage, a solution containing 15-20% ammonia. Zinc oxide was isolated from the first filtrate by distillation of ammonia, and then the precipitate was separated on a filter. Copper oxide is isolated from the second filter, ammonia stripping, which is also separated on the filter.

The disadvantage of this method, according to the totality of the features that are the prototype of the present invention, is the lack of an independent operation for the separation of iron from solutions and the contamination of products with a mouse

An object of the invention is to provide an additional product, an iron oxide pigment, and to reduce the arsenic content of the product.

The goal is achieved in that

in the known method for the complex processing of pyrite cinders, including leaching of non-ferrous metals and subsequent separation of copper and zinc compounds, the leaching of cinder is carried out with sulfuric acid solutions, copper is isolated by cementation after iron scrap is added, and after oxidation, an oxidizing agent and an alkaline reagent are introduced to achieve O, B .P. 370 mV and pH 3.5. the x-containing precipitate formed is isolated to the mouse; the value of O. V.P. is raised in the solution. up to 600 mV and direct it to the deposition of iron hydroxide, from which

after heat treatment, an iron-oxide pigment is obtained, and then zinc compounds and a mouse-containing cinder are combined with the tail pulp of the sediment after extraction of useful components and sent to

warehousing.

PRI me R. After leaching of the pyrite cinder from firing of sulfur pyrite, weak solutions of sulfuric acid and cementation deposition of copper with

pH 2.8, containing, g / l: iron (III) 0.5. iron (II) 10.1, zinc 1.8. copper 0.017, mouse to 0.055, iron (III) sulfate salt was introduced to various values of O. V.P., after which it was neutralized to pH 3.5, the precipitate was separated from the solution, hydrogen peroxide was added with a rise of O. B .P. addOOmV and ammonia, raising the pH to 4.0. The resulting iron hydroxide precipitate was separated from the solution and calcined at 700 ° C. Structure

received precipitation is given in the table.

From the above example it follows that the proposed method allows to obtain iron oxide pigment with a content of arsenic of less than 0.001%, which is practically

completely removes the limitations of its use.

fifty

(56) Copyright certificate of the USSR No. 1157101, cl. C 22 V 15 / 00.1984.

Claims (1)

The claims METHOD FOR COMPREHENSIVE PROCESSING OF PYRITE CARBONS, including leaching of non-ferrous metals and subsequent extraction of copper and zinc, characterized in that, in order to obtain a high-quality end product - iron oxide pigment with a reduced content of arsenic, copper is isolated by cementation after adding iron scrap to achieve O.V.P. in O solution - 80 mV, and after copper cementation, the oxidizing agent is dosed to O.V.P. solution 370 mV, then support the value of O.V.P. on the At this level, an alkaline reagent is dosed until a solution pH of 3.5 is reached, after which the solution is separated from the x-containing precipitate that forms a mouse, and O.V.P. is raised in the solution. up to 600 mV and send it to precipitate iron hydroxide, from which, after heat treatment, an iron oxide pigment and zinc carbonate are obtained, 8 a mouse-containing precipitate is combined with the tail of the cinder after extraction of useful components and sent for storage.