Method for producing high-purity nano-zinc oxide by ammonia method using electrolytic zinc acid-leaching residues

Abstract

The invention discloses a method for producing high-purity nano-zinc oxide by an ammonia method using electrolytic zinc acid-leaching residues. The method comprises the following steps of: adding slaked lime being 1-5% of the mass of electrolytic zinc acid-leaching residues before a leaching step to perform activation, then leaching with ammonia-ammonium bicarbonate solution, adding 0.3-0.5kg of sodium fluorosilicate to per cubic meter of ammonia-ammonium bicarbonate solution, and refining after performing purification and impurity removal. According to the method for producing high-purity nano-zinc oxide by ammonia method using electrolytic zinc acid-leaching residues, the electrolytic zinc acid-leaching residues can be leached efficiently, the high-purity nano-zinc oxide with the purity up to above 99.7% can be obtained, and the high-purity nano-zinc oxide has high practical value and economic value; all the valuable and harmful heavy metals in the electrolytic zinc acid-leaching residues are leached and utilized, so that the obtained final leaching residues are converted from electrolytic zinc acid-leaching residues as high hazard wastes into ordinary solid wastes, the environment is protected, and the resources are rationally utilized.

Description

Technical field

[0001] The invention relates to a method for producing zinc oxide, in particular to a method for producing high-purity nano zinc oxide. Background technique

[0002] At present, hydro-zinc smelting mainly adopts the production process of roasting-leaching-electrolysis. The zinc content in the discharged electrolytic zinc acid leaching slag is generally 6-9% by mass, and some can reach 20%. The phase analysis and X-ray diffraction analysis show that the zinc in the leaching residue is mainly composed of ZnFe 2 O 4、 It exists in the form of zinc silicate. At the same time, the mass content of sulfur is 6-12%, of which the mass content of sulfate is 15-30%. The content of calcium and magnesium salts varies from place to place, and it also contains Cu. 2+ , Pb 2+ , Cd 2+ , Ni 2+ , Hg 2+ , As 3+ The approximate mass content of plasma is about: copper 1%, lead 0.8%, iron 4%, silicon 3%, arsenic 0.3%, silver 0.003%, calcium 12%, and magnesium 3%. In order to recover th...

Examples

Embodiment 1

[0090] A method for producing high-purity nano-zinc oxide by using electrolytic zinc acid leaching residue ammonia method, which sequentially includes the following steps:

[0091] (1) Activation: Take 500 grams of electrolytic zinc acid leaching residue (in terms of mass ratio, containing 8.6% zinc, 1.03% copper, 32% calcium sulfate, 0.05% cadmium, and 0.03% arsenic), add 25 grams of hydrated lime for activation , The activation time is 36 hours;

[0092] (2) Extraction: prepare 1500ml ammonia leaching solution, of which NH 3 The concentration is 6mol / L, CO 3 2- The concentration is 1mol / L, 0.3kg of sodium fluorosilicate is added to each cubic meter of ammonia-carbon ammonium solution, and the activated electrolytic zinc acid leaching residue is added to the above ammonia leaching solution for three-stage leaching, each stage leaching The extraction time is 2 hours. After solid-liquid separation, the zinc-ammonia complex solution obtained contains 38.9 grams of zinc (90.5% zinc re...

Embodiment 2

[0099] A method for producing high-purity nano-zinc oxide by using electrolytic zinc acid leaching residue ammonia method, which sequentially includes the following steps:

[0100] (1) Activation: Take 500 grams of acid leaching residue (zinc 7.6%, copper 0.83%, calcium sulfate 28%, cadmium 0.045%, arsenic 0.02%), add 5 grams of slaked lime for activation, the activation time is 40 hours;

[0101] (2) Extraction: prepare 1500ml ammonia leaching solution, of which NH 3 The concentration is 5mol / L, CO 3 2- The concentration is 1.2 mol / L, 0.5kg of sodium fluorosilicate is added to each cubic meter of ammonia-carbon ammonium solution, and 0.04kg of surfactant SDS is added to each cubic meter of ammonia-carbon ammonium solution; 0.8kg of dicyandiamine is also added to each cubic meter of ammonia-carbon ammonium solution; the activated electrolytic zinc acid leaching residue is added to the above ammonia leaching solution for three-stage leaching. The leaching is performed at the same tim...

Embodiment 3

[0110] A method for producing high-purity nano-zinc oxide by using electrolytic zinc acid leaching residue ammonia method, which sequentially includes the following steps:

[0111] (1) Activation: Take 1500 grams of acid leaching residue (zinc 9.0%, copper 0.80%, calcium sulfate 30%, cadmium 0.040%, arsenic 0.25%, silicon 3%, arsenic 0.3%, silver 0.003%, magnesium 3%), Add 45 grams of slaked lime for activation, the activation time is 48 hours;

[0112] (2) Extraction: prepare 1500ml ammonia leaching solution, of which NH 3 The concentration is 5.5mol / L, CO 3 2- The concentration is 0.9mol / L, 0.5kg of sodium fluorosilicate is added to each cubic meter of ammonia-carbon ammonium solution, and 0.03kg of surfactant SDS is added to each cubic meter of ammonia-carbon ammonium solution; 1kg of dicyandiamide is added to each cubic meter of ammonia-carbon ammonium solution; the activated electrolytic zinc acid leaching residue is added to the above ammonia leaching solution for three-stage...

Technical field

[0001] The invention relates to a method for producing zinc oxide, in particular to a method for producing high-purity nano zinc oxide. Background technique

[0002] At present, hydro-zinc smelting mainly adopts the production process of roasting-leaching-electrolysis. The zinc content in the discharged electrolytic zinc acid leaching slag is generally 6-9% by mass, and some can reach 20%. The phase analysis and X-ray diffraction analysis show that the zinc in the leaching residue is mainly composed of ZnFe 2 O 4、 It exists in the form of zinc silicate. At the same time, the mass content of sulfur is 6-12%, of which the mass content of sulfate is 15-30%. The content of calcium and magnesium salts varies from place to place, and it also contains Cu. 2+ , Pb 2+ , Cd 2+ , Ni 2+ , Hg 2+ , As 3+ The approximate mass content of plasma is about: copper 1%, lead 0.8%, iron 4%, silicon 3%, arsenic 0.3%, silver 0.003%, calcium 12%, and magnesium 3%. In order to recover th...

Examples

Embodiment 1

[0090] A method for producing high-purity nano-zinc oxide by using electrolytic zinc acid leaching residue ammonia method, which sequentially includes the following steps:

[0091] (1) Activation: Take 500 grams of electrolytic zinc acid leaching residue (in terms of mass ratio, containing 8.6% zinc, 1.03% copper, 32% calcium sulfate, 0.05% cadmium, and 0.03% arsenic), add 25 grams of hydrated lime for activation , The activation time is 36 hours;

[0092] (2) Extraction: prepare 1500ml ammonia leaching solution, of which NH 3 The concentration is 6mol / L, CO 3 2- The concentration is 1mol / L, 0.3kg of sodium fluorosilicate is added to each cubic meter of ammonia-carbon ammonium solution, and the activated electrolytic zinc acid leaching residue is added to the above ammonia leaching solution for three-stage leaching, each stage leaching The extraction time is 2 hours. After solid-liquid separation, the zinc-ammonia complex solution obtained contains 38.9 grams of zinc (90.5% zinc re...

Embodiment 2

[0099] A method for producing high-purity nano-zinc oxide by using electrolytic zinc acid leaching residue ammonia method, which sequentially includes the following steps:

[0100] (1) Activation: Take 500 grams of acid leaching residue (zinc 7.6%, copper 0.83%, calcium sulfate 28%, cadmium 0.045%, arsenic 0.02%), add 5 grams of slaked lime for activation, the activation time is 40 hours;

[0101] (2) Extraction: prepare 1500ml ammonia leaching solution, of which NH 3 The concentration is 5mol / L, CO 3 2- The concentration is 1.2 mol / L, 0.5kg of sodium fluorosilicate is added to each cubic meter of ammonia-carbon ammonium solution, and 0.04kg of surfactant SDS is added to each cubic meter of ammonia-carbon ammonium solution; 0.8kg of dicyandiamine is also added to each cubic meter of ammonia-carbon ammonium solution; the activated electrolytic zinc acid leaching residue is added to the above ammonia leaching solution for three-stage leaching. The leaching is performed at the same tim...

Embodiment 3

[0110] A method for producing high-purity nano-zinc oxide by using electrolytic zinc acid leaching residue ammonia method, which sequentially includes the following steps:

[0111] (1) Activation: Take 1500 grams of acid leaching residue (zinc 9.0%, copper 0.80%, calcium sulfate 30%, cadmium 0.040%, arsenic 0.25%, silicon 3%, arsenic 0.3%, silver 0.003%, magnesium 3%), Add 45 grams of slaked lime for activation, the activation time is 48 hours;

[0112] (2) Extraction: prepare 1500ml ammonia leaching solution, of which NH 3 The concentration is 5.5mol / L, CO 3 2- The concentration is 0.9mol / L, 0.5kg of sodium fluorosilicate is added to each cubic meter of ammonia-carbon ammonium solution, and 0.03kg of surfactant SDS is added to each cubic meter of ammonia-carbon ammonium solution; 1kg of dicyandiamide is added to each cubic meter of ammonia-carbon ammonium solution; the activated electrolytic zinc acid leaching residue is added to the above ammonia leaching solution for three-stage...