Process for reclaiming aluminum from waste paper and packaging products
OwnerGuilherme C. Donalisioinventor
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Abstract
Aluminum is recovered from organic waste paper and packaging material containing aluminum foil by heating the waste material in a kiln or other such device to decompose the organic constituents in the waste material, preferably by pyrolysis, producing hot gaseous by-products with a carbonaceous ash residue containing aluminum. The ash residue is contacted with an aqueous solution of sulfuric acid under conditions which cause the aluminum to react with the sulfuric acid to produce aluminum sulfate. Preferably, the ash/acid contacting is carried out with a relatively dilute sulfuric acid solution and at an elevated temperature in the range of from about 80.degree. C. to about 100.degree. C. to produce Al.sub.2 (SO.sub.4).sub.3.18H.sub.2 O as the reaction product.
Claims7
A process for recovering aluminum from organic waste material containing aluminum comprising the steps of heating the waste material in a rotary kiln under conditions of pyrolysis to decompose organic constituents in the waste material to produce a carbonaceous ash residue containing elemental aluminum and hot gaseous by-products and contacting the ash residue from the kiln with an aqueous solution of sulfuric acid under conditions which yield high purity, essentially iron-free aluminum sulfate as a reaction product in the solution.
A process for recovering aluminum from organic waste material containing aluminum comprising the steps of comminuting the waste material, washing the comminuted waste material with water to remove solid and/or liquid impurities, conveying the washed comminuted waste material to a rotary kiln, drying the waste material in the kiln by exposing the material to a relatively low temperature of less than about 300.degree. C., pyrolyzing the dried material in the kiln to produce a carbonaceous ash residue containing elemental aluminum and hot gaseous by-products, contacting the ash residue from the kiln with an aqueous solution of sulfuric acid under conditions which yield a high purity, essentially iron-free aluminum sulfate as a reaction product in the solution.
Dependencies are inferred from the claim text.