Faculty Publications

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    Defluoridation of fresh water using the process of Electrocoagulation combined with Adsorption
    (2013) Wali, A.; Saidutta, M.B.
    In India, fluoride is the major inorganic pollutant of natural origin found in groundwater. Fluoride pollution occurs due to natural and manmade reasons and high concentrations have a detrimental effect on health. Electrochemical techniques like Electrocoagulation(EC) appears to be one of the most effective approaches for treatment of water and wastewater because of its versatility, safety, selectivity, amenability to automation and environmental compatibility. Results show that the percentage removal of fluoride was around 94 to 96% for monopolar and bipolar electrodes. Adsorbents like tricalcium phosphate and activated alumina used along with electrocoagulation process also gave promising results. © 2013 CAFET-INNOVA TECHNICAL SOCIETY.
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    Influence of planetary ball milling parameters on the mechano-chemical activation of fly ash
    (Elsevier, 2015) Patil, A.G.; Anandhan, S.
    This study illustrates the design of statistical analysis by Taguchi methodology to obtain nanostructured fly ash by planetary ball milling. An orthogonal array and analysis of variance were employed to analyze the effect of milling parameters. A class-F fly ash was subjected to planetary ball milling induced mechano-chemical activation aided by a surfactant. Ball milling parameters, such as ball-to-powder weight ratio, type and quantity of surfactant and type of medium were varied as guided by the Taguchi design. The nanostructured fly ash was characterized by dynamic light scattering, BET surface area analysis, X-ray diffraction, FTIR spectroscopy, scanning electron microscopy, field emission scanning electron microscopy and transmission electron microscopy. The ball-to-powder weight ratio and the surfactant type are the major influencing factors on lower crystallite size and average particle size and higher specific surface area. The surface modification of fly ash was confirmed by FTIR spectroscopy. The nano fly ash produced by this method has a wide application potential in polymer industries as reinforcement in composites. © 2015 Elsevier B.V.
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    Customizable ceramic nanocomposites using carbon nanotubes
    (MDPI AG indexing@mdpi.com Postfach Basel CH-4005, 2019) Okolo, C.; Rafique, R.; Sagar, S.S.; Subhani, T.; Saharudin, M.S.; Badekai Ramachandra, B.R.; Inam, F.
    A novel tweakable nanocomposite was prepared by spark plasma sintering followed by systematic oxidation of carbon nanotube (CNT) molecules to produce alumina/carbon nanotube nanocomposites with surface porosities. The mechanical properties (flexural strength and fracture toughness), surface area, and electrical conductivities were characterized and compared. The nanocomposites were extensively analyzed by field emission scanning electron microscopy (FE-SEM) for 2D qualitative surface morphological analysis. Adding CNTs in ceramic matrices and then systematically oxidizing them, without substantial reduction in densification, induces significant capability to achieve desirable/application oriented balance between mechanical, electrical, and catalytic properties of these ceramic nanocomposites. This novel strategy, upon further development, opens new level of opportunities for real-world/industrial applications of these relatively novel engineering materials. © 2019 by the authors
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    Improving landfill liner performance with bentonite-slag blend permeated with ammonia for a Municipal solid waste landfill
    (Academic Press, 2024) Aswathy, A.; Sunil, B.M.
    Leachate emanating from landfills contains ammonia which may cause serious health effects on living things. An effectively designed clay barrier should not allow the contaminant to infiltrate the soil and groundwater systems. The utilization of certain industrial by-products in engineered landfill barriers, not only reduces the need for conventional liner materials but also helps in sustainable waste management. This study investigated the hydraulic conductivity, unconfined compressive strength, compaction, and adsorption characteristics of lithomargic clay blended with an optimum percentage of bentonite (10%) and granulated blast furnace slag (15%) permeated with ammonia. The results revealed that increasing the content of granulated blast furnace slag decreased the maximum dry density while increasing the optimum moisture content. In comparison to lithomargic clay, the hydraulic conductivity of the amended soil liner permeated with ammonia decreased from a value of 3 × 10−8 m/s to 5 × 10−10 m/s. The unconfined compressive strength of the amended soil specimens showed an increasing trend with curing times (i.e., 0, 14, 28, and 56 days). The batch adsorption results revealed that Freundlich and Langmuir's isotherm fits the equilibrium adsorption data and the adsorption of ammonia on clay liner follows non-linear behaviour. Overall, the experimental results implied that lithomargic clay blended with 10% bentonite and 15% granulated blast furnace slag can be used as an impermeable soil reactive barrier in engineered landfills. © 2024 Elsevier Ltd
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    Numerical and Experimental Investigation of Thermal Barrier Effects of CNT-Reinforced Fly Ash/Alumina Coatings in Diesel Engine Pistons
    (American Chemical Society, 2025) Chavana, N.; Sarkar, B.; Jambagi, S.C.
    Fly ash (FA), an industrial byproduct from coal combustion, presents significant disposal challenges, especially in developing nations. Given its mineralogical properties, FA shows potential in thermal spray coatings. This study evaluates FA-based coatings for pistons to improve thermal management in internal combustion engines through numerical simulations, analyzing their effects on the temperature distribution, thermal stress, and combustion efficiency. FA coatings were also applied to marine-grade steel with additives (50 wt % Al2O3 and 0-2 wt % CNT) to assess high-temperature performance. Microstructural analysis revealed that 2 wt % CNT-reinforced (2CAF) coatings showed agglomeration, reducing microhardness by ?9.27% compared to 1 wt % CNT-reinforced (1CAF) coatings. The XRD analysis of 1CAF indicated ?56.51% transformation of corundum to ?-alumina, lowering thermal conductivity by ?15.40% compared to alumina/FA (AF) coatings, while 2CAF coatings showed increased conductivity due to CNT inhomogeneity. For piston applications, simulations showed an ?24.59% rise in maximum surface temperature, from 241.39 to 300.76 °C, and an ?62.06% reduction in heat flux, indicating enhanced durability and reduced cold-start emissions. Thermal cycling demonstrated that 1CAF coatings outlasted AF and 2CAF, suggesting FA-based TBCs as sustainable and economical options for enhanced engine performance and waste valorization. © 2025 American Chemical Society.
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    Exploring pore solution chemistry and solid phase assemblies in cement-based electrolytes for potential structural batteries
    (Elsevier B.V., 2025) Sundaramoorthi, S.; Palanisamy, T.
    This study develops a sustainable cement-based electrolyte for a cement-based battery by incorporating supplementary cementitious materials (SCMs) and epsom salt to enhance electrical performance. Ionic composition and liquid-phase characterization revealed that SCM and epsomite reduced [Ca2+] and [OH?] ion concentration while modulating [SO42?] concentration in the pore solution, depending on the SCM type. Silica fume-based mixes, with lower reactive alumina content, showed increased [SO42?] and higher ionic strength. The SF5E mix exhibited superior electrical performance, achieving a 56 % higher discharge life. Cyclic voltammetry indicated quasi-reversible behaviour with hybrid capacitive-faradaic characteristics, confirming its suitability for energy storage. The microstructural analysis highlighted the stable C–S–H formation, ensuring mechanical integrity alongside electrical functionality. The findings establish SF5E as the optimal electrolyte, demonstrating a balance between ionic conductivity and structural stability. By linking cement chemistry with battery performance, this work lays the foundation for a scalable, self-sustaining energy storage system for applications in structural health monitoring. © 2025 Elsevier B.V.