Efficacy of sustainable polymers to mitigate the negative effects of anisotropic clay minerals in flotation and dewatering operations

The depletion of high-grade ore resources and ongoing demand for mineral products has led to an increase in the exploitation of low-grade and complex ores, which often contain colloid clay particles (e.g., kaolinite) that are detrimental to flotation and dewatering unit operations in mineral process...

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Main Authors: N. Molaei, J. Forster, M. Shoaib, O. Wani, S. Khan, E. Bobicki
Format: Article
Language:English
Published: Elsevier 2022-06-01
Series:Cleaner Engineering and Technology
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2666790822000751
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author N. Molaei
J. Forster
M. Shoaib
O. Wani
S. Khan
E. Bobicki
author_facet N. Molaei
J. Forster
M. Shoaib
O. Wani
S. Khan
E. Bobicki
author_sort N. Molaei
collection DOAJ
description The depletion of high-grade ore resources and ongoing demand for mineral products has led to an increase in the exploitation of low-grade and complex ores, which often contain colloid clay particles (e.g., kaolinite) that are detrimental to flotation and dewatering unit operations in mineral processing. During flotation, clay particles increase the pulp viscosity and produce a slime coating by adsorption on the surface of valuable minerals resulting in the reduction of the flotation grade and recovery. Clay particles are also suspended in mine tailings that can cause dewatering challenges in flocculation operations. The clay mitigation strategies employed during flotation (dilution and use of dispersants) and dewatering (addition of flocculants) involve reagents from non-renewable sources that can have deleterious consequences on the environment and aquatic biota. As part of an effort to find environmentally benign reagents, we evaluated the performance of six sustainable polymers (protein- and polysaccharide-based biopolymers) for their potential as dispersants and flocculants of kaolinite clay particles. Their effectiveness was assessed via chalcopyrite froth flotation, settling, and turbidity tests. Zeta potential, adsorption isotherm by total organic carbon, and X-ray scattering tests were also conducted to understand the interactions between biopolymers and kaolinite mineral surfaces. At pH 7 and 10, the anionic polysaccharide pectin showed promising dispersant efficiency in flotation and the cationic protein protamine significantly improved kaolinite flocculation in dewatering operation. Outcomes of this investigation demonstrate that commercially available sustainable polymers or “biopolymers” have a significant potential to use to mitigate the negative effects of clay particles in minerals processing to reduce environmental issues arising from inorganic and synthetic organic reagents from non-renewable sources.
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spelling doaj.art-8ae08d459fbd45ca920be98b6eca5fbc2022-12-22T02:26:42ZengElsevierCleaner Engineering and Technology2666-79082022-06-018100470Efficacy of sustainable polymers to mitigate the negative effects of anisotropic clay minerals in flotation and dewatering operationsN. Molaei0J. Forster1M. Shoaib2O. Wani3S. Khan4E. Bobicki5Department of Materials Science and Engineering, University of Toronto, Toronto, ON, Canada; Corresponding author.Department of Materials Science and Engineering, University of Toronto, Toronto, ON, CanadaDepartment of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, CanadaDepartment of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, CanadaDepartment of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, CanadaDepartment of Materials Science and Engineering, University of Toronto, Toronto, ON, Canada; Corresponding author.The depletion of high-grade ore resources and ongoing demand for mineral products has led to an increase in the exploitation of low-grade and complex ores, which often contain colloid clay particles (e.g., kaolinite) that are detrimental to flotation and dewatering unit operations in mineral processing. During flotation, clay particles increase the pulp viscosity and produce a slime coating by adsorption on the surface of valuable minerals resulting in the reduction of the flotation grade and recovery. Clay particles are also suspended in mine tailings that can cause dewatering challenges in flocculation operations. The clay mitigation strategies employed during flotation (dilution and use of dispersants) and dewatering (addition of flocculants) involve reagents from non-renewable sources that can have deleterious consequences on the environment and aquatic biota. As part of an effort to find environmentally benign reagents, we evaluated the performance of six sustainable polymers (protein- and polysaccharide-based biopolymers) for their potential as dispersants and flocculants of kaolinite clay particles. Their effectiveness was assessed via chalcopyrite froth flotation, settling, and turbidity tests. Zeta potential, adsorption isotherm by total organic carbon, and X-ray scattering tests were also conducted to understand the interactions between biopolymers and kaolinite mineral surfaces. At pH 7 and 10, the anionic polysaccharide pectin showed promising dispersant efficiency in flotation and the cationic protein protamine significantly improved kaolinite flocculation in dewatering operation. Outcomes of this investigation demonstrate that commercially available sustainable polymers or “biopolymers” have a significant potential to use to mitigate the negative effects of clay particles in minerals processing to reduce environmental issues arising from inorganic and synthetic organic reagents from non-renewable sources.http://www.sciencedirect.com/science/article/pii/S2666790822000751BiopolymersDewateringClay particlesMicroflotationTotal organic carbon (TOC)Zeta potential
spellingShingle N. Molaei
J. Forster
M. Shoaib
O. Wani
S. Khan
E. Bobicki
Efficacy of sustainable polymers to mitigate the negative effects of anisotropic clay minerals in flotation and dewatering operations
Cleaner Engineering and Technology
Biopolymers
Dewatering
Clay particles
Microflotation
Total organic carbon (TOC)
Zeta potential
title Efficacy of sustainable polymers to mitigate the negative effects of anisotropic clay minerals in flotation and dewatering operations
title_full Efficacy of sustainable polymers to mitigate the negative effects of anisotropic clay minerals in flotation and dewatering operations
title_fullStr Efficacy of sustainable polymers to mitigate the negative effects of anisotropic clay minerals in flotation and dewatering operations
title_full_unstemmed Efficacy of sustainable polymers to mitigate the negative effects of anisotropic clay minerals in flotation and dewatering operations
title_short Efficacy of sustainable polymers to mitigate the negative effects of anisotropic clay minerals in flotation and dewatering operations
title_sort efficacy of sustainable polymers to mitigate the negative effects of anisotropic clay minerals in flotation and dewatering operations
topic Biopolymers
Dewatering
Clay particles
Microflotation
Total organic carbon (TOC)
Zeta potential
url http://www.sciencedirect.com/science/article/pii/S2666790822000751
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AT owani efficacyofsustainablepolymerstomitigatethenegativeeffectsofanisotropicclaymineralsinflotationanddewateringoperations
AT skhan efficacyofsustainablepolymerstomitigatethenegativeeffectsofanisotropicclaymineralsinflotationanddewateringoperations
AT ebobicki efficacyofsustainablepolymerstomitigatethenegativeeffectsofanisotropicclaymineralsinflotationanddewateringoperations