Alkali-Activated Materials in Environmental Technology Applications

Alkali-Activated Materials in Environmental Technology Applications
Copyright
Contents
List of contributors
Preface
1 Alkali-activated materials in environmental technology: introduction
	1.1 Scope of this book
	1.2 Definition of the key terminology
	1.3 The origins of alkali-activated materials
	1.4 Beyond construction materials
	1.5 Summary
	References
2 Chemistry and materials science of alkali-activated materials
	2.1 Fundamental chemistry
		2.1.1 Reactivity in alkaline media
		2.1.2 Low CaO-content aluminosilicate sources
		2.1.3 High CaO-content aluminosilicate sources
		2.1.4 Moderate CaO-content aluminosilicate sources
	2.2 Structural models
		2.2.1 Structural models for C-S-H gel
		2.2.2 Structural models for N-A-S-H gel
	2.3 Concluding remarks
	References
3 Geopolymeric nanomaterials
	3.1 Introduction
	3.2 Primer of geopolymer chemistry for syntheses of geopolymeric nanomaterials
		3.2.1 Geopolymerization reaction
		3.2.2 Geopolymerization as “top-down” synthetic process
		3.2.3 Geopolymer—an innately “nanostructured” material
	3.3 Examples of geopolymer nanomaterial synthesis and applications
		3.3.1 Synthesis and applications of nanoporous geopolymer with meso- and macropores
			3.3.1.1 Synthesis
			3.3.1.2 Arsenic removal from ground water
			3.3.1.3 Catalysts for biodiesel production
		3.3.2 Exploration of geopolymer chemistry for small particle production and applications
			3.3.2.1 Synthesis
			3.3.2.2 Antimicrobial application
			3.3.2.3 Bacterial toxin removal in therapeutic application
			3.3.2.4 Energy-saving multifunctional hybrid additives in asphalt
	3.4 Concluding remarks
	References
4 Highly porous alkali-activated materials
	4.1 Introduction
	4.2 Material porosity
	4.3 Effect of composition and synthesis conditions
		4.3.1 In situ zeolite formation
	4.4 Micro- and mesoporous filler addition
	4.5 Process induced porosity
	4.6 Direct foaming
	4.7 Templating agents
	4.8 Additive manufacturing
	4.9 Summary and conclusions
	References
5 Granulation techniques of geopolymers and alkali-activated materials
	5.1 Introduction
	5.2 Granulation techniques
		5.2.1 Wet granulation
		5.2.2 Fluidized bed granulation
	5.3 Granulation of alkaline-activated materials
		5.3.1 High shear granulation and heat formation
		5.3.2 Suspension dispersion solidification method and foaming
	5.4 Properties of granules
	5.5 Utilization of geopolymer granules
		5.5.1 As adsorbents in wastewater treatment
	5.6 Other applications
	5.7 Conclusions
	References
6 Surface chemistry of alkali-activated materials and how to modify it
	6.1 Introduction
	6.2 Surface characteristics and properties of alkali-activated materials
		6.2.1 Nuclear magnetic resonance spectroscopy
		6.2.2 Infrared spectroscopy
		6.2.3 Raman spectroscopy
		6.2.4 X-ray photoelectron spectroscopy
		6.2.5 Surface charge properties
		6.2.6 Specific surface area and nanometer-scale porosity
		6.2.7 Other analytical techniques
	6.3 Modification methods of alkali-activated materials
		6.3.1 Surface modification with organosilicon compounds
		6.3.2 Surface esterification
		6.3.3 Acid or base treatment
		6.3.4 Ion exchange
		6.3.5 Composite materials
		6.3.6 Conversion into zeolites
	6.4 Conclusions
	References
7 Alkali-activated materials as adsorbents for water and wastewater treatment
	7.1 Introduction
	7.2 Occurring trends in scientific literature
	7.3 Different strategies to use alkali-activated materials as adsorbents
	7.4 Water pollutants removed by alkali-activated materials
	7.5 Adsorption of heavy metals by AAMs
	7.6 Adsorption of dyes by AAMs
	7.7 Adsorption of other water pollutants by AAMs
	7.8 Regeneration after sorption
	7.9 Bridging the gap between bench-scale studies and pilot-scale trials
	7.10 Performance comparison with benchmark materials
	7.11 Conclusions and future trends
	Acknowledgments
	References
8 Alkali-activated materials as photocatalysts for aqueous pollutant degradation
	8.1 Introduction
	8.2 Alkali-activated materials and geopolymers
	8.3 Geopolymer-based photocatalysts
		8.3.1 Supported geopolymer-based heterogeneous photocatalysts
			8.3.1.1 TiO2-supported geopolymer based photocatalysts
			8.3.1.2 Photocatalysts based on other catalytically active metal oxides supported on geopolymer substrates
		8.3.2 Geopolymer composites as photocatalysts
		8.3.3 Alkali-activated materials as photocatalysts
	8.4 Concluding remarks
		8.4.1 Summary of the chapter
		8.4.2 Shortcomings of the reported literature
		8.4.3 Prospects for the future development of these photocatalysts
	References
9 Alkali-activated membranes and membrane supports
	9.1 Introduction
	9.2 Ceramic materials in membrane technology
	9.3 Alkali-activated materials as membranes
		9.3.1 Preparation of alkali-activated membranes
		9.3.2 Properties and applications of alkali-activated membranes
	9.4 Conversion of alkali-activated membranes into zeolites
	9.5 Conclusions
	References
10 Alkali-activated materials in passive pH control of wastewater treatment and anaerobic digestion
	10.1 Introduction
	10.2 Reasons for high pH in the pore solutions of alkali-activated materials
	10.3 Utilization prospects for alkali-activated materials in pH control
		10.3.1 Anaerobic digestion
		10.3.2 Nitrification
		10.3.3 Acid mine drainage
		10.3.4 Preparation of alkali-activated materials for pH control applications
	10.4 Properties of alkali-activated pH control materials
	10.5 Conclusion
	References
11 Alkali-activated materials for catalytic air pollution control
	11.1 Introduction
		11.1.1 Geopolymer features
	11.2 Photocatalysis in air pollution control context
	11.3 Use of geopolymer structure as adsorbent and incorporation of transition metals
		11.3.1 Generation of active sites within the structure
		11.3.2 Dispersion of oxides by ion exchange
		11.3.3 Deposition and impregnation of other catalytic species
	11.4 Self-cleaning materials
		11.4.1 Self-cleaning testing
	11.5 Summaries on the reported cases studies and practical considerations
	11.6 Conclusion
	References
12 Adsorption of gaseous pollutants by alkali-activated materials
	12.1 Air emissions
		12.1.1 CO2 emission and capture
	12.2 Alkali-activated materials as potential adsorbents
		12.2.1 Geopolymers as CO2 adsorbents
		12.2.2 Geopolymer composites for CO2 adsorption
			12.2.2.1 Geopolymer composites: addition or nucleation of zeolites for CO2 adsorbents at low temperature
			12.2.2.2 Geopolymer composites: addition of hydrotalcites for CO2 adsorbents at intermediate temperature
	12.3 Alternative use and activation of fly ashes for the removal of gaseous pollutants
	12.4 Conclusions and future challenges
	References
13 Solidification/stabilization of hazardous wastes by alkali activation
	13.1 Introduction
	13.2 Chemistry of solidification/stabilization of heavy metals in alkali-activated materials
		13.2.1 Speciation of cationic heavy metals in alkali-activated materials
		13.2.2 Speciation of oxyanionic heavy metals in alkali-activated materials
		13.2.3 Proposed mechanisms of heavy metal immobilization in geopolymer
			13.2.3.1 Charge balancing of Al tetrahedra
			13.2.3.2 Precipitation mechanism
			13.2.3.3 Covalent bonding mechanism
			13.2.3.4 Physical encapsulation mechanism
	13.3 Stabilization/solidification of real wastes
		13.3.1 Municipal waste
			13.3.1.1 Ashes from municipal solid waste incineration
			13.3.1.2 Waste from sewage sludge incineration
		13.3.2 Industrial waste
			13.3.2.1 Ash from coal and biomass power plants
			13.3.2.2 Mining tailings and wastes
				Gold mine tailings
				Zinc and copper-zinc mine tailings
				Chromite ore processing residue
			13.3.2.3 Smelting slags and metallurgical wastes
				Lead/zinc slags
				Antimony, ferrochrome, ferronickel, and lithium slags
			13.3.2.4 Electroplating sludge
			13.3.2.5 Tannery sludge
			13.3.2.6 Red mud
		13.3.3 Other wastes
	13.4 Effect of alkaline activator
	13.5 Effect of Si/Al ratio
	13.6 Effect of metal dose
	13.7 Effect of sulfide
	13.8 Effect of calcium
	13.9 Effect of aging and kinetics of leaching
	13.10 pH of leaching solution
	13.11 Sequential extraction
	13.12 Comparison with Portland cement
	13.13 Conclusions
	Abbreviations
	References
14 In situ sediment remediation with alkali-activated materials
	14.1 Introduction
	14.2 Factors affecting pollutant release from the sediment
	14.3 Remediation of contaminated sediments
	14.4 Alkali-activated materials: a brief introduction
	14.5 Alkali-activated materials as active caps or sediment amendment
	14.6 Conclusions
	References
15 Antimicrobial alkali-activated materials
	15.1 Introduction
	15.2 Some material solutions against bacteria
	15.3 A state-of-the-art on antimicrobial alkali-activated materials
	15.4 A facile manufacturing, efficient formulations, and evaluation for antibacterial alkali-activated materials
		15.4.1 Raw materials for the hosting matrix
		15.4.2 Antibacterial agents
		15.4.3 Manufacturing process
		15.4.4 Measuring the antibacterial efficiency of alkali-activated materials
			15.4.4.1 Preparation of culture medium and susceptibility testing
			15.4.4.2 The halo method to determine the antibacterial efficiency
		15.4.5 Microstructural characterization and activity evaluation against Escherichia coli and Staphylococcus aureus using si...
		15.4.6 Activity evaluation against Escherichia coli and Staphylococcus aureus using copper oxide as an antibacterial agent
		15.4.7 Activity evaluation against Escherichia coli and Staphylococcus aureus using triclosan as an antibacterial agent
		15.4.8 Antibacterial efficiency of 6-year-old alkali-activated materials
		15.4.9 Important highlights to consider on the antibacterial alkali-activated material formulations
	15.5 Comments and future opportunities on antimicrobial alkali-activated materials
	Acknowledgments
	References
16 Alkali-activated materials as catalysts in chemical processes
	16.1 Introduction
	16.2 Synthesis of geopolymer catalysts
		16.2.1 Geopolymers as supports for other catalytically active species
		16.2.2 Geopolymer composites
	16.3 Applications of geopolymer catalysts in chemical processes
		16.3.1 Geopolymers as solid acid catalysts
			16.3.1.1 Beckmann rearrangement reactions
			16.3.1.2 Friedel–Crafts aromatic alkylation reactions
			16.3.1.3 Friedel–Crafts acylation reactions
		16.3.2 Geopolymers as solid base catalysts
		16.3.3 Geopolymers as redox catalysts
		16.3.4 Geopolymer-based catalysts for other chemical processes
	16.4 Concluding remarks
	References
17 Environmental performance of alkali-activated materials in environmental technology applications
	17.1 Introduction
	17.2 Environmental performance of alkali-activated materials
		17.2.1 Environmental performance of alkali-activated materials as binders in concrete products
		17.2.2 Environmental performance of alkali activated materials application for thermal stability and insulation
		17.2.3 Environmental performance of alkali activated materials application in waste treatment
	17.3 Conclusions
	References
18 Drivers and barriers for productization of alkali-activated materials in environmental technology
	18.1 Introduction
	18.2 General technical description of adsorption processes and cost structure in water or wastewater treatment
	18.3 Pathway of productizing a new adsorbent
	18.4 Legislation and standards
		18.4.1 Waste regulation
		18.4.2 REACH regulation
		18.4.3 Regulation-related water and wastewater treatment
	18.5 Conclusions
	References
Index