Boksyty lubelskie jako surowiec do otrzymywania tlenku glinu metodą kwaśną
Abstract
LUBLIN BAUXITES AS A RAW MATERIAL FOR PRODUCING ALUMINA BY THE BRETSZNAJDER'S METHOD
Summary
Possible application of Lublin Bauxite-bearing ore deposits to production of alumina by Bretsznajder's method has been investigated. Iron contained in the raw material (about 22% of Fe2O3) has been removed by both sedimentation and chemical methods. The boehmite concentrates obtained as a result of purification of the raw material by sedimentation and by chemical method contain 7% and 4% of Fe2O3, respectively. The experiments involving leaching of concentrates, filtration of the solutions as well as the hydrolysis of basic ammonium aluminum sulfate have been carried out on a laboratory scale. Hydrated aluminum oxide which has been obtained as a result of these processes was converted into α-Al2O3 modification (with 99% yield) by heating at 1473 K for 2 hrs. The final product is characterized by high purity (99.75% Al2O3) and physicochemical properties very close to those of the imported brands of aluminum oxide. Preliminary studies on concentration of rare elements associated with aluminum (Ti, Zr, Nb, Th, Ga) have revealed that these elements are mainly collected in the wastes resulting from pressure leaching.
Summary
Possible application of Lublin Bauxite-bearing ore deposits to production of alumina by Bretsznajder's method has been investigated. Iron contained in the raw material (about 22% of Fe2O3) has been removed by both sedimentation and chemical methods. The boehmite concentrates obtained as a result of purification of the raw material by sedimentation and by chemical method contain 7% and 4% of Fe2O3, respectively. The experiments involving leaching of concentrates, filtration of the solutions as well as the hydrolysis of basic ammonium aluminum sulfate have been carried out on a laboratory scale. Hydrated aluminum oxide which has been obtained as a result of these processes was converted into α-Al2O3 modification (with 99% yield) by heating at 1473 K for 2 hrs. The final product is characterized by high purity (99.75% Al2O3) and physicochemical properties very close to those of the imported brands of aluminum oxide. Preliminary studies on concentration of rare elements associated with aluminum (Ti, Zr, Nb, Th, Ga) have revealed that these elements are mainly collected in the wastes resulting from pressure leaching.