Faculty Publications
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Item Coconut coir pith, available in abundance especially in tropical countries, was studied as a substrate for the production of cellulase[1,4(1,3;1,4)???D?glucan 4?glucanohydrolase, EC 3.2.1.4] and ??D?glucosidase(??D?glucoside glucohydrolase, EC 3.2.1.21) in solid state fermentation. The effects of fermentation time, nutrient level, substrate particle size and inoculum size have been examined for optimal production of these enzymes by the fungal strain Aspergillus niger NCIM 1005. The highest filter paper activity (FPA) of 4.11 IU g?1, carboxyl methyl cellulose (CMCase) activity of 15·55 IU g?1 and cellobiase activity of 9·31 IU g?1 were obtained after 7 to 8 days of fermentation. Reese and Mandel's mineral solution in the substrate to mineral solution ratio of 1:10 (w/v) supported high cellulase and cellobiase activities. An inoculum size of 20–50% (v/v) based on the volume of mineral medium and substrate average particle size of 375 ?m were optimum for enzyme production. Copyright © 1994 SCI(Production of cellulases from coconut coir pith in solid state fermentation) Muniswaran, P.K.A.; Selvakumar, P.; Charyulu, N.C.L.N.1994Item Hydrogen Sulfide Removal in Biofilter: Evaluation of a new filter material by immobilization of thiobacillus sp(Walter de Gruyter GmbH peter.golla@degruyter.com, 2009) Potumarthi, R.; Anupoju, G.R.; Mugeraya, G.; Jetty, A.Different agricultural residue was evaluated as a biofilter material for the removal of Hydrogen sulfide (H2S) using Thiobacillus sp. A Combination of four different agricultural residues, viz., sugarcane bagasse, coconut coir pith, rice husk and saw dust were evaluated as biofilter material. From results, it was observed that filter material having composition of 2:4:2:2, 4:4:2:2 and 4:2:2:4 has resulted in retaining 70% moisture content at the end of 10 days. The biofilter was operated for 128 days in three phases by varying inlet H2S concentration from 321 to 2020 ppmv. Biofilter exhibited 100% removal efficiency (RE) at an inlet concentration of 570 ppmv, 99% RE at an inlet concentration of 1416 ppmv and 66% RE at a maximum inlet concentration of 2020 ppmv. The filter performance in terms of RE, dropped to 48% when the air was not humidified before sending to the filter, which has direct relation with the MC of the filter material. The RE recovered to 66% with recovery of moisture content (MC) to 57% upon subsequent re-introduction of the humidifier in to the circuit. The pH has dropped from 7.8 to 4.8 during the course of operation of the filter. H2S was effectively removed under different operating conditions using mixed agricultural residue as filter material. However humidification was most essential to maintain the required moisture content in the biofilter. SEM analysis has shown the good growth of Thiobacillus sp. in the filter bed and hence the new material proved to be good support for the immobilization of Thiobacillus sp. Copyright © 2009 The Berkeley Electronic Press. All rights reserved.Item Morphological and thermal properties of maize fiber composites(Korean Fiber Society, 2012) Saravana Bavan, D.; Mohan Kumar, G.C.Maize stalk has become one of the major sources of fibers from the agricultural residues. Use of these fibers as a reinforcement in the polymer is described in this paper. The present work is focused on establishing the properties such as physical, chemical, morphological structure and thermal properties of maize stalk fiber using different characterization techniques. Simple hand layup method was followed for processing the composite material. Chemical treatments of fibers were carried out to study the interaction of fibers with the matrix. The results revealed that maize fibers can also be used as a traditional fiber as reinforcement in a natural fiber reinforced composite materials. © 2012 The Korean Fiber Society and Springer Science+Business Media Dordrecht.Item Wear response of walnut-shell-reinforced epoxy composites(ASTM International, 2017) Doddamani, M.; Parande, G.; Manakari, V.; Siddhalingeshwar, I.G.; Gaitonde, V.N.; Gupta, N.Present work utilizes agricultural by-product, walnut shell, as reinforcing filler in epoxy matrix for investigating dry sliding wear behavior using a pin-on disc wear-testing machine. Effects of sliding velocity (0.5-1.5 m/s), normal load (10-50 N), sliding distance (1000-3000 m) and filler content (10-30 wt. %) on wear rate (Wt), specific wear rate (Ws) and coefficient of friction (?) are investigated. The experiments were planned as per design of the experiments scheme and the wear characteristics were analyzed through response surface modeling (RSM) method. The lowest Wt of 1.1 mm3/km was noted for 1.5 m/s sliding velocity with 30-wt. % filler content. Sliding distance did not have a significant influence on Ws above a critical load of 40 N. The minimum ? was observed at 1-m/s sliding velocity, 40-N load, 1000-m sliding distance, and 30-wt. % filler. Lower values of Wt and ? at higher walnut-shell loadings support feasibility of using such composites in wear-prone applications. The wear mechanism was determined in the composites using extensive scanning electron microscopic observations. © © 2017 by ASTM International.Item A Study on Areca nut Husk Fibre Extraction, Composite Panel Preparation and Mechanical Characteristics of the Composites(Springer, 2019) Muralidhar, N.; Kaliveeran, V.; Arumugam, V.; Srinivasula Reddy, I.Areca nut husk fibre is an agricultural waste, which does not contribute to the economy of areca nut plantation. The use of areca nut husk fibre as reinforcing material in the preparation of low-cost and lightweight composites provides utility value to areca nut husk fibre. Low-cost and lightweight composites have wide range of applications in construction industry, marine structures, automobile industry and aerospace industry. The present work focuses on extraction of areca nut husk fibre with alkali treatment process by using 6% of sodium hydroxide solution, composite panel preparation and determination of mechanical properties of composite panels. Different fibre compositions (fine fibre, coarse fibre and coarse fibre sandwiched with glass fibre) of 15% by weight were used in the present study. Tensile, flexural and impact tests were conducted to find the mechanical characteristics the composite materials. The tensile strength of composites made with fine fibre (15.1 MPa) is observed to be more than that of composites made with coarse fibre (10.8 MPa). Further improvement in tensile strength of composite panels made of coarse areca nut husk fibre layer sandwiched with two layers of glass fibre (24.8 MPa) is observed. The flexural strength of fine fibre composites is more when compared to that of the coarse fibre composites. The average flexural strength of composites reinforced with fine fibre, coarse fibre and coarse fibre sandwiched with glass fibre is observed as 73 MPa, 66.7 MPa and 284 MPa, respectively. The impact strength of coarse fibre composites is found to be higher when compared to that of fine fibre composites. © 2019, The Institution of Engineers (India).Item Combustion, performance, and emission characteristics of dairy-washed milk scum biodiesel in a dual cylinder compression ignition engine(Taylor and Francis Inc. 325 Chestnut St, Suite 800 Philadelphia PA 19106, 2020) Srikanth, H.V.; Venkatesh, J.; Godiganur, S.; Manne, B.; Bharath Kumar, S.; Spurthy, S.The present work has been carried out to study the suitability of milk dairy waste scum (MDWS) biodiesel as a fuel for diesel engine. The investigations were carried out on performance, emission and combustion characteristics of a direct injection dual cylinder diesel engine fueled with MDWS methyl ester, and their blends. Two-step transesterification process was used to synthesize the MDWS biodiesel, characterization according to specified ASTM D6751-15C standards. The performance characteristics studies showed an increased brake thermal efficiency of B20 (3%) and B30 (0.94%) blends in comparison to fossil diesel. However, the increased brake specific fuel consumption (BSFC) was also found with all the fuel blends and an higher (9%) BSFC was obtained with B50 compared to diesel fuel at full load condition. The emissions of blends were found to be lower in comparison with diesel fuel, except for nitrogen oxides. A 32% increase in NOx emission was found with B50 blend compared to diesel fuel at maximum load condition. However, improved combustion characteristics would found with MDWS blends with respect to in-cylinder pressure, ignition delay, and heat release rate compared to fossil diesel. © 2019 Taylor & Francis Group, LLC.Item Emulsification of bio-crude produced from agricultural waste via hydrothermal liquefaction process(Elsevier Ltd, 2021) Bhat, S.; Borugadda, V.B.; Dalai, A.K.In the present study, bio-crude obtained from hydrothermal liquefaction of waste wheat flour and canola meal (residue after extraction of canola oil) was emulsified with the light cycle oil (LCO) using octanol as an emulsifier. Emulsification process parameters such as mixing time, temperature, stirring intensity, and emulsifier, bio-crude, LCO concentrations were varied and studied to obtain a final emulsion that could be used as a fuel in diesel engines. Favorable process conditions for the emulsion were found to be 25 min of mixing time at 105 ? temperature with a stirring intensity of 1000 rpm, and emulsifier, bio-crude, and LCO concentrations as 5, 10, and 85 wt% respectively. Various physicochemical properties of the formulated emulsion with bio-crude were studied which showed an improvement compared to the bio-crude used. The physicochemical properties of the emulsion were compared with the blends of conventional diesel fuel that do not contain additives, canola biodiesel for emulsion stability. Comparative analysis of the emulsion physicochemical properties revealed that the emulsion properties are very close to ASTM D 6751-09 biodiesel specifications. © 2021 Elsevier LtdItem Nutmeg seed shell biochar as an effective adsorbent for removal of remazol brilliant blue reactive dye: kinetic, isotherm, and thermodynamic study(Taylor and Francis Ltd., 2022) Thomas, T.; Thalla, A.K.Biochar derived from agricultural wastes has emerged as an effective adsorbent for wastewater treatment. However, studies on nutmeg seed shell (NSS) utilization in textile wastewater treatment is limited. This study explores the possibility and efficacy of using a modified nutmeg seed shell as an adsorbent to remove remazol brilliant blue reactive dye (RBBR) from the aqueous wastewater. The adsorbent was characterized before and after adsorption using FTIR, FE-SEM, TGA, and XRD, respectively. Response surface methodology (RSM), based on Box–Behnken design (BBD), was utilized to optimize the effects of initial concentration (5–100 mg/L), pH (2–12), contact time (10–120 min), and adsorbent dosage (0.5–3 g/L) on the RBBR removal. The quadratic model generated by RSM describes the best relationship between the independent parameters and the dye removal efficiency. The optimum conditions for the RBBR dye removal were observed at an initial concentration of 100 mg/L, adsorbent dose of 2.85 g, pH of 10, and contact time of 110 min, which resulted in 93.41% removal efficiency. The adsorption model fits the pseudo-second-order and Langmuir isotherm models with correlation factors (R2) > 0.99. Langmuir adsorption isotherm gives an optimum adsorption capacity of 173.31 mg/g. The adsorption isotherm and kinetics study shows that the adsorption process is based on monolayer chemisorption. The thermodynamic studies suggest that adsorption is a spontaneous and endothermic process. The result indicates that modified NSS is an efficient adsorbent for removing reactive dye RBBR. © 2022 Taylor & Francis Group, LLC.Item A review on analysis of biochar produced from microwave-assisted pyrolysis of agricultural waste biomass(Elsevier B.V., 2023) Ramesh, R.; Surya, D.V.; Sankar Rao, C.S.; Yadav, A.; Sridevi, V.; Remya, N.Every year the agricultural product processing industries produce large quantities of agricultural waste biomass (AWB). Whose disposal has become a serious issue concerning solid waste management due to environmental and health issues. Microwave-assisted pyrolysis (MAP) is an intriguing technology for producing valuable products from waste feedstocks. AWB is converted into a valuable product like biochar by using MAP. The conversion of AWB into biochar by MAP is influenced by several factors such as type of feedstock, pyrolysis temperature, residence time, pressure, heating rate, susceptor, particle size, and microwave power. However, no review article is available to understand the role of MAP on biochar production from AWB. The current review focused on understanding the fundamentals of biochar production. It also reviews the challenges in producing biochar process by compatible, acceptable, and sustainable and its future directions to gain economic benefits even at small-scale applications. The generation of biochar from MAP and its uses in agriculture are discussed. The current review would address the knowledge gap and highlight the critical implications in biochar production and applications. © 2023 Elsevier B.V.Item Comprehensive Characterization of Novel Jute Fabrics with Musa Paradisiaca Leaf Agro-Waste Based Micro Cellulosic Fillers Reinforced Epoxy Composites For Lightweight Applications(Korean Fiber Society, 2025) Indra Reddy, M.I.; Sethuramalingam, P.; Sahu, R.K.For lightweight, sustainable, high-strength products, hybrid bio-epoxy composites materials were the most excellent choice for the production industry. The investigation proceeds in developing a four-stacked sequence jute-woven mats reinforced with epoxy composite and added with micro-cellulose fillers. The extraction of micro cellulose from Musa paradisiaca plant leaf (MPPL) was carried out through a series of processes, including alkali treatment, acid hydrolysis, bleaching, and slow pyrolysis. The composite was fabricated using the conventional hand lay-up method and compression molding. The microcellulose was added to the stacked composite at varying weight percentages (0, 2.5, 5, 7.5, and 10%). Thermo-mechanical and water intake characterization were investigated using ASTM. The findings revealed that incorporating 5% MPPL cellulose into the jute-stacked layer sequence resulted in improved hardness (95 HRRW), tensile modulus (3407.69 MPa), tensile strength (79.74 MPa), flexural modulus (2195.752 MPa), flexural strength (56.87 MPa), and crystallinity index (72.7%). However, a reduction in impact strength (23.27 kJ/m2) was noted compared to the unfilled composite. The higher thermal degradation (480 °C) behavior of the filler-reinforced composite makes them a suitable material for applications in high-temperature environments. Fractographical morphology was also investigated to reveal the bonding behavior, voids formations, agglomeration of fillers, and fracture behavior. Thus, this distinguishable composite characterization will aid the manufacturing industries in producing high-strength biodegradable materials. © The Author(s), under exclusive licence to the Korean Fiber Society 2025.