Cargando…

Extraction of alumina and silica from high-silica bauxite by sintering with sodium carbonate followed by two-step leaching with water and sulfuric acid

Efficient utilization of high-silica bauxite and minimization of bauxite residue are of great significance for the sustainable development of the alumina industry. In this paper, a novel process is proposed to extract Al(2)O(3) and SiO(2) from high-silica bauxite without residue discharge, that is,...

Descripción completa

Detalles Bibliográficos
Autores principales: Sun, Yue, Pan, Aifang, Ma, Yuzhao, Chang, Jie
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society of Chemistry 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10394738/
https://www.ncbi.nlm.nih.gov/pubmed/37538514
http://dx.doi.org/10.1039/d3ra03362g
_version_ 1785083437685669888
author Sun, Yue
Pan, Aifang
Ma, Yuzhao
Chang, Jie
author_facet Sun, Yue
Pan, Aifang
Ma, Yuzhao
Chang, Jie
author_sort Sun, Yue
collection PubMed
description Efficient utilization of high-silica bauxite and minimization of bauxite residue are of great significance for the sustainable development of the alumina industry. In this paper, a novel process is proposed to extract Al(2)O(3) and SiO(2) from high-silica bauxite without residue discharge, that is, sintering bauxite with Na(2)CO(3) followed by two-step leaching with water and sulfuric acid. The effects of the sintering parameters on the process were investigated, and the phase transformations during sintering and leaching were revealed by using phase diagram, thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) methods. When the mixture of the high-silica bauxite and Na(2)CO(3) with mole ratio of Na(2)O/(Al(2)O(3) + SiO(2)) of 1 was sintered at 950 °C for 30 min, diaspore and kaolinite were primarily converted into Na(1.95)Al(1.95)Si(0.05)O(4) and an amorphous phase, respectively. In the water leaching process, Na(1.95)Al(1.95)Si(0.05)O(4) was dissolved while the amorphous phase underwent some transformations to form the water leaching residue, resulting in ∼84% of Al(2)O(3) being extracted for alumina production. In the sulfuric acid leaching process, the amorphous phase in the water leaching residue dissolved, resulting in ∼13% of Al(2)O(3) and ∼86% of SiO(2) being extracted for the production of polyaluminium ferric sulfate (PAFS) and silica gel, respectively. The silica gel had a high purity, containing more than 88% of SiO(2) after drying.
format Online
Article
Text
id pubmed-10394738
institution National Center for Biotechnology Information
language English
publishDate 2023
publisher The Royal Society of Chemistry
record_format MEDLINE/PubMed
spelling pubmed-103947382023-08-03 Extraction of alumina and silica from high-silica bauxite by sintering with sodium carbonate followed by two-step leaching with water and sulfuric acid Sun, Yue Pan, Aifang Ma, Yuzhao Chang, Jie RSC Adv Chemistry Efficient utilization of high-silica bauxite and minimization of bauxite residue are of great significance for the sustainable development of the alumina industry. In this paper, a novel process is proposed to extract Al(2)O(3) and SiO(2) from high-silica bauxite without residue discharge, that is, sintering bauxite with Na(2)CO(3) followed by two-step leaching with water and sulfuric acid. The effects of the sintering parameters on the process were investigated, and the phase transformations during sintering and leaching were revealed by using phase diagram, thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) methods. When the mixture of the high-silica bauxite and Na(2)CO(3) with mole ratio of Na(2)O/(Al(2)O(3) + SiO(2)) of 1 was sintered at 950 °C for 30 min, diaspore and kaolinite were primarily converted into Na(1.95)Al(1.95)Si(0.05)O(4) and an amorphous phase, respectively. In the water leaching process, Na(1.95)Al(1.95)Si(0.05)O(4) was dissolved while the amorphous phase underwent some transformations to form the water leaching residue, resulting in ∼84% of Al(2)O(3) being extracted for alumina production. In the sulfuric acid leaching process, the amorphous phase in the water leaching residue dissolved, resulting in ∼13% of Al(2)O(3) and ∼86% of SiO(2) being extracted for the production of polyaluminium ferric sulfate (PAFS) and silica gel, respectively. The silica gel had a high purity, containing more than 88% of SiO(2) after drying. The Royal Society of Chemistry 2023-08-02 /pmc/articles/PMC10394738/ /pubmed/37538514 http://dx.doi.org/10.1039/d3ra03362g Text en This journal is © The Royal Society of Chemistry https://creativecommons.org/licenses/by-nc/3.0/
spellingShingle Chemistry
Sun, Yue
Pan, Aifang
Ma, Yuzhao
Chang, Jie
Extraction of alumina and silica from high-silica bauxite by sintering with sodium carbonate followed by two-step leaching with water and sulfuric acid
title Extraction of alumina and silica from high-silica bauxite by sintering with sodium carbonate followed by two-step leaching with water and sulfuric acid
title_full Extraction of alumina and silica from high-silica bauxite by sintering with sodium carbonate followed by two-step leaching with water and sulfuric acid
title_fullStr Extraction of alumina and silica from high-silica bauxite by sintering with sodium carbonate followed by two-step leaching with water and sulfuric acid
title_full_unstemmed Extraction of alumina and silica from high-silica bauxite by sintering with sodium carbonate followed by two-step leaching with water and sulfuric acid
title_short Extraction of alumina and silica from high-silica bauxite by sintering with sodium carbonate followed by two-step leaching with water and sulfuric acid
title_sort extraction of alumina and silica from high-silica bauxite by sintering with sodium carbonate followed by two-step leaching with water and sulfuric acid
topic Chemistry
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10394738/
https://www.ncbi.nlm.nih.gov/pubmed/37538514
http://dx.doi.org/10.1039/d3ra03362g
work_keys_str_mv AT sunyue extractionofaluminaandsilicafromhighsilicabauxitebysinteringwithsodiumcarbonatefollowedbytwostepleachingwithwaterandsulfuricacid
AT panaifang extractionofaluminaandsilicafromhighsilicabauxitebysinteringwithsodiumcarbonatefollowedbytwostepleachingwithwaterandsulfuricacid
AT mayuzhao extractionofaluminaandsilicafromhighsilicabauxitebysinteringwithsodiumcarbonatefollowedbytwostepleachingwithwaterandsulfuricacid
AT changjie extractionofaluminaandsilicafromhighsilicabauxitebysinteringwithsodiumcarbonatefollowedbytwostepleachingwithwaterandsulfuricacid