Refinement of industrial kaolin by removal of iron-bearing impurities using thiourea dioxide under mechanical activation
Source abstract
Abstract
Abstract This study reports a series of experiments conducted to evaluate the suitability of thiourea dioxide (TD) under mechanical activation, in bleaching iron-bearing impurities from raw kaolin. The optimum conditions for the maximum whiteness of 76.32% were determined as follows: rotation speed of ball mill, 400 rpm; activation time, 1.5 h; TD dosage, 0.8% of kaolin mass; solid-to-liquid ratio, 1:2; pH, 8.0; room temperature. The effect of grinding causes the partial surface amorphization of kaolin particles and a decrease in the dehydroxylation temperature. The assistance of grinding leads to a higher iron removal when compared with the conventional bleaching method using sodium hydrosulfite.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Clay minerals and soil interactions · Iron oxide chemistry and applications · Minerals Flotation and Separation Techniques
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (16)
Show source-provided references
1. Improvements to the quantitative assay of nonrefractory minerals for Fe (II) and total Fe using 1,10-phenanthroline10.1346/CCMN.1998.0460106 ↗
2. Synthesis and characterization of mullite-zirconia nanostructured composite by combined mechanical activation and reaction sintering10.1016/j.apt.2015.08.001 ↗
3. A study of the factors controlling the adsorption of Cr (III) on modified montmorillonites10.1046/j.1365-2389.2001.00413.x ↗
4. Influence of iron kaolin whitness: an electron paramagnetic resonance study10.1016/j.clay.2010.04.022 ↗
5. Iron removal from kaolin using binuclear rare earth complex activated thiourea dioxide10.1016/j.clay.2016.03.002 ↗
6. Slow transformation of mechanically dehydroxylated kaolinite to kaolinite–an aged mechanochemically activated formamide-intercalated kaolinite study10.1016/S0040-6031(03)00316-2 ↗
7. Study on the kinetics of iron oxide leaching by oxalic acid10.1016/j.minpro.2006.03.012 ↗
8. Dissolution of iron oxide using oxalic acid10.1016/j.hydromet.2007.02.005 ↗
9. Recent developments in the chemistry of thiourea oxides10.1002/chem.201403453 ↗
10. Industrial clays case study
11. Peng · 1982
12. Hydrothermal (200 °C) synthesis and crystal chemistry of iron-rich kaolinites10.1180/claymin.1990.025.2.04 ↗
13. Designing and optimization of separation process of iron impurities from kaolin by oxalic acid in bench-scale stirred-tank reactor10.1016/j.clay.2015.01.010 ↗
14. Microbial formation of a halloysite-like mineral10.1346/CCMN.2005.0530303 ↗
15. Thurlow · 2001
16. Three dimensional reduced graphene hydrogels with tunable pore sizes using thiourea dioxide for electrode materials in supercapacitors10.1016/j.electacta.2015.07.150 ↗