Simultaneous and clean separation of titanium, iron, and alumina from coal fly ash in one spot: Electrolysis-hydrolysis method

doi:10.1016/j.seppur.2022.121247

	Simultaneous and clean separation of titanium, iron, and alumina from coal fly ash in one spot: Electrolysis-hydrolysis method
	Shi, Yuan 2; Jiang, Kai-xi 3; Zhang, Ting-an 1; Zhu, Xiao-feng 2
刊名	Separation and Purification Technology
	2022-08-01
卷号	294
关键词	Additives Alumina Aluminum oxide Coal Coal ash Electrolysis Extraction Heavy metals Hematite Hydrolysis Iron Metal recovery Silica Slags Sulfuric acid Titanium dioxide Waste heat Alumina extractions Coal fly ash Hydrolysis methods Hydrolysis process Iron extraction Large amounts Separation and extraction Titania Titania-alumina Titanium extraction
ISSN号	1383-5866
DOI	10.1016/j.seppur.2022.121247
英文摘要	Large amounts of heavy-metal-containing coal fly ash can cause serious environmental hazards. The separation and extraction of titanium, iron, and alumina from coal fly ash can provide economic and environmental benefits. This work presents an electrolysis-hydrolysis method to alter the precipitation order of iron and alumina by changing the ion charge sequence to extract iron and alumina in an orderly manner while recovering the waste heat to polymerize the precipitated titanium. The separation and extraction of titanium, iron, and alumina in one spot can shorten the process and make full use of the electric energy. Under optimal conditions, the efficiencies of iron, titanium, and alumina were 97.6%, 93.1% and 88.5%, respectively. The iron product had a composition of 95.8% Fe2O3, 0.5% Al2O3, 0.3% CaO, 0.1% SO3, and 0.4% TiO2. The alumina product had a composition of 88.7% Al2O3, 0.1% Fe2O3, 0.2% CaO, 9.1% SO3 and 0.2% TiO2. The titanium product had a composition of 63.78% TiO2, 3.11% Al2O3, 8.15% Fe2O3, 0.28% CaO, 4.12% SiO2, and 9.6% SO3. Moreover, in the entire electrolysis process, no expensive membranes or chemical additives were required, avoiding the limitations of membranes and high costs. Fe, Al(OH)3, Ti(OH)4, O2, and H2 were generated during the electrolysis-hydrolysis process; therefore, no harmful substances were produced. Thus, this study proposes an alternative electrolysis-hydrolysis process for the simultaneous separation and extraction of titanium, alumina, and iron from coal fly ash leachate in one spot. © 2022 Elsevier B.V.
WOS研究方向	Engineering
语种	英语
出版者	Elsevier B.V.
WOS记录号	WOS:000806015100008
内容类型	期刊论文
源URL	[http://ir.lut.edu.cn/handle/2XXMBERH/158494]
专题	材料科学与工程学院
作者单位	1.Key Laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Ministry of Education, Special Metallurgy and Process Engineering Institute, School of Metallurgy, Northeastern University, Shenyang; 110819, China; 2.State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals, Lanzhou University of Technology, Lanzhou; 730050, China; 3.College of Zijin Mining, Fuzhou University, Fuzhou; 350000, China
推荐引用方式 GB/T 7714	Shi, Yuan,Jiang, Kai-xi,Zhang, Ting-an,et al. Simultaneous and clean separation of titanium, iron, and alumina from coal fly ash in one spot: Electrolysis-hydrolysis method[J]. Separation and Purification Technology,2022,294.
APA	Shi, Yuan,Jiang, Kai-xi,Zhang, Ting-an,&Zhu, Xiao-feng.(2022).Simultaneous and clean separation of titanium, iron, and alumina from coal fly ash in one spot: Electrolysis-hydrolysis method.Separation and Purification Technology,294.
MLA	Shi, Yuan,et al."Simultaneous and clean separation of titanium, iron, and alumina from coal fly ash in one spot: Electrolysis-hydrolysis method".Separation and Purification Technology 294(2022).