Faculty Publications

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    Phase transformation, structural evolution and mechanical property of nanostructured FeAl as a result of mechanical alloying
    (2009) Rajath Hegde, M.M.R.; Surendranathan, A.O.
    Objective of the work was to synthesize nanostructured FeAl alloy powder by mechanical alloying (MEA). The work concentrated on synthesis, characterization, structural and mechanical properties of the alloy. Nanostructured FeAl intermetallics were prepared directly by MEA in a high energy rate ball mill. Milling was performed under toluene solution to avoid contamination from the milling media and atmosphere. Mixtures of elemental Fe and Al were progressively transformed into a partially disordered solid solution with an average composition of Fe-50 at % Al. Phase transformation, structural changes, morphology, particle size measurement and chemical composition during MEA were investigated by X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDS) respectively. Vickers micro hardness (VMH) indentation tests were performed on the powders. XRD and SEM studies revealed the alloying of elemental powders as well as transition to nanostructured alloy, crystallite size of 18 nm was obtained after 28 hours of milling. Expansion/contraction in lattice parameter accompanied by reduction in crystallite size occurs during transition to nanostructured alloy. Longer milling duration introduces ordering in the alloyed powders as proved by the presence of superlattice reflection. Elemental and alloyed phase coexist while hardness increased during MEA. © 2009 Allerton Press, Inc.
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    Effective oxidation of alcohols by Iron(III)-Schiff base-triphenylphosphine complexes
    (2010) Rani, S.; Badekai Ramachandra, B.
    Iron(III)-Schiff base-triphenylphosphine complexes catalyze the oxidation of alcohols to their corresponding carbonyl compounds in presence of hydrogen peroxide in good yields. © 2010 Elsevier Ltd. All rights reserved.
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    Degradation of paracetamol in aqueous solution by Fenton Oxidation and photo-Fenton Oxidation processes using iron from Laterite soil as catalyst
    (2011) Manu, B.; Mahamood
    For the treatment of paracetamol in water, the photo-Fenton Oxidation process and Classic Fenton oxidation process have been demonstrated and found effective. An iron catalyst extracted from lateritic soil is used to exhibit the degradation and mineralization of paracetamol. Paracetamol reduction and chemical oxygen demand (COD) removal are measured as the objective functions to be maximized. The experimental conditions of the degradation of paracetamol are optimized by Fenton process. the optimum conditions observed for 10 mg/L initial paracetamol concentration are influent pH 3, initial H 2O 2 dosage 30 mg/L, [paracetamol]/[H 2O 2] ratio 1:3 (w/w) and [H 2O 2] / [Laterite iron] ratio 30:0.75 (w/w). At the optimum conditions, for 10 mg/L of initial paracetamol concentration, 76% paracetamol reduction and 69% COD removal by Fenton oxidation and 79% paracetamol reduction and 77% COD removal by UV-C Fenton process are observed in 120 minutes reaction time. At the above optimum conditions, HPLC analysis has demonstrated 100% removal of paracetamol for Fenton oxidation process in 240 minutes and for UV-C photo- Fenton process in 120 minutes. The methods are effective and they may be used in the paracetamol industry. © 2011 CAFET-INNOVA TECHNICAL SOCIETY.
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    Low cost Fenton's oxidative degradation of 4-nitroaniline using iron from laterite
    (IWA Publishing 12 Caxton Street London SW1H 0QS, 2016) Amritha, A.S.; Manu, B.
    The present study aims to establish the use of iron (Fe) from larerite in the case of Fenton's oxidation process which is a simple and cost-effective method for degradation of nitro compounds in effluents and in surface or ground water. 4-nitroaniline (4-NA) degradation by Fenton's oxidation method is the subject of the present study so as to optimize pH, hydrogen peroxide/iron (H/F) ratio at different initial concentrations of 4-NA. The optimum pH obtained was 3. The present study has also established optimum H/F ratio for the different initial concentrations of 4-NA for both conventional and use of Fe from laterite. The maximum removal efficiency of 99.84% was obtained for an H/F ratio of 100 for 0.5 mM initial concentration of 4-NA. The study establishes the use of Fe extracted from locally available laterite soil (LS) as a replacement of Fe salts so as to reduce the cost of the process. © 2016 IWA Publishing.
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    Fenton's treatment of actual agriculture runoff water containing herbicides
    (IWA Publishing 12 Caxton Street London SW1H 0QS, 2017) Sangami, S.; Manu, B.
    This research was to study the efficiency of the Fenton's treatment process for the removal of three herbicides, namely 2,4-dichlorophenoxy acetic acid (2,4-D), ametryn and dicamba from the sugarcane field runoff water. The treatment process was designed with the Taguchi approach by varying the four factors such as H 2 O 2 /COD (1-3.5), H 2 O 2 /Fe 2+ (5-50), pH (2-5) and reaction time (30-240 min) as independent variables. Influence of these parameters on chemical oxygen demand (COD), ametryn, dicamba and 2,4-D removal efficiencies (dependent variables) were investigated by performing signal to noise ratio and other statistical analysis. The optimum conditions were found to be H 2 O 2 /COD: 2.125, H 2 O 2 /Fe 2+ : 27.5, pH: 3.5 and reaction time of 135 min for removal efficiencies of 100% for ametryn, 95.42% for dicamba, 88.2% for 2,4-D and with 75% of overall COD removal efficiencies. However, the percentage contribution of H 2 O 2 /COD ratio was observed to be significant among all four independent variables and were 44.16%, 67.57%, 51.85% and 50.66% for %COD, ametryn, dicamba and 2,4-D removal efficiencies, respectively. The maximum removal of herbicides was observed with the H 2 O 2 dosage of 5.44 mM and Fe 2+ dosage of 0.12 mM at pH 3.5. © IWA Publishing 2017 W.
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    Effects of electric potential, NaCl, pH and distance between electrodes on efficiency of electrolysis in landfill leachate treatment
    (Taylor and Francis Inc. 325 Chestnut St, Suite 800 Philadelphia PA 19106, 2017) Erabee, I.K.; Ahsan, A.; Jose, B.; Arunkumar, T.; Sathyamurthy, R.; Idrus, S.; Daud, N.N.N.
    This study investigated the effects of different parameters on the removal efficiencies of organic and inorganic pollutants in landfill leachate treatment by electrolysis. Different parameters were considered such as the electric potential (e.g., 24, 40 and 60 V), hydraulic retention time (HRT) (e.g., 40, 60, 80, 100 and 120 min), sodium chloride (NaCl) concentration (e.g., 1, 3, 5 and 7%), pH (e.g., 3, 7 and 9), electrodes materials [e.g., aluminum (Al) and iron (Fe)] and distance between electrodes (e.g., 1, 2 and 3 cm). The best operational condition of electrolysis was then recommended. The electric potential of 60 V with HRT of 120 min at 5% of NaCl solution using Al as anode and Fe as cathode (kept at a distance of 3 cm) was the most efficient condition which increased the removal efficiencies of various parameters such as turbidity, salinity, total suspended solids (TSS), total dissolved solids (TDS), biochemical oxygen demand (BOD), chemical oxygen demand (COD) and heavy metals (e.g., Zn and Mn). The higher removal percentages of many parameters, especially COD (94%) and Mn (93%) indicated that the electrolysis is an efficient technique for multi-pollutants (e.g., organic, inorganic and heavy metals) removal from the landfill leachate. © 2017 Taylor & Francis Group, LLC.
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    Influence of Granulated Blast Furnace Slag and Cement on the Strength Properties of Lithomargic Clay
    (Springer India sanjiv.goswami@springer.co.in, 2017) C. Sekhar, D.C.; Nayak, S.; Preetham, H.K.
    Utilizing industrial byproducts in soil stabilization benefits the economic, environmental and social benefits. Granulated blast furnace slag is a byproduct of iron and steel industry having oxides similar to that of cement but in different proportions. This study describes experimental results achieved by the use of granulated blast furnace slag (GBFS) and cement in stabilizing lithomargic clay for geotechnical applications. Soil was replaced by GBFS in percentages of 10, 15, 20, 25, 30, 35, 40, 45, 50% and cement of 2, 4, 6, and 8% by dry weight of soil is added. Various experimental studies like specific gravity, Atterberg limits, compaction, UCS, CBR and triaxial compression test, were performed on samples to understand the effect of these mixes on their few index and strength properties. The study also includes an investigation on a combination of optimum percentage of GBFS with varying percentage of cement and lime on their shear parameters. The study result shows significant improvement in the strength properties of the mixes. Hence it can be concluded that lithomargic clay stabilized with GBFS and cement/lime satisfy the strength requisite to be employed in the numerous geotechnical applications. © 2017, Indian Geotechnical Society.
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    Degradation of nitroaromatic compounds: a novel approach using iron from laterite soil
    (Springer Verlag, 2018) Amritha, A.S.; Manu, B.
    The Fenton’s oxidation process has been found to be a simple and economical method for the treatment of nitroaromatic compounds in water. In the present study, the iron extracted from the laterite soil was used as a catalyst and optimization of pH, hydrogen peroxide concentration and iron concentration was studied for different initial concentrations of 2-nitroaniline (2-NA), 3-nitroaniline (3-NA) and 4-nitroaniline (4-NA). The optimum pH obtained was 2.5 for 2-NA and 3-NA and 3 for 4-NA. The maximum removal efficiency obtained was 85.3%, 84.3% and 98.7% for 0.5 mM initial concentration at a hydrogen peroxide concentration of 3.5 mM, 4.5 mM and 5 mM for 2-NA, 3-NA and 4-NA, respectively, with a constant iron concentration of 0.05 mM. © 2018, The Author(s).
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    Bacteriological synthesis of iron hydroxysulfate using an isolated Acidithiobacillus ferrooxidans strain and its application in ametryn degradation by Fenton's oxidation process
    (Academic Press, 2019) Bhaskar, S.; Manu, B.; Sreenivasa, M.Y.
    The investigation reports the application of biogenic jarosite, an iron hydroxy sulfate mineral in Fenton's Oxidation process. Ametryn, a herbicide detrimental to aquatic life and also to human is treated by Fenton's oxidation process using synthesized iron mineral, jarosite. The jarosite synthesis was carried out by using an isolated Acidithiobacillus ferrooxidans bacterial strain with ferrous as an iron supplement. The isolated strain was characterized by molecular techniques and biooxidation activity to ferrous to ferric iron was checked. On Fenton's treatment ametryn degradation upto 84.9% and COD removal to the extent of 56.1% was observed within 2 h of treatment and the reaction follows the pseudo first order kinetics with the curve best fit. The slight increase in kinetic rate constant on jarosite loading rate increase from 0.1 g/L to 0.5 g/L with H2O2 dosage of 100 mg/L confirms that jarosite has a catalytic role in the removal of ametryn. Mass spectroscopy analysis of treated synthetic ametryn solution at various intervals reveal the degradation follows dealkylation and hydroxylation pathway with the formation of three major intermediate compounds discussed here. © 2018 Elsevier Ltd