Publications (30)44.33 Total impact
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Article: A chemo-biological treatment of scrubbing water from power plants with recovery of value-added products
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ABSTRACT: A chemo-biological approach for treating sulphate-rich effluent generated during wet scrubbing of flue gas emissions from fossil fuel fired power plants has been discussed. Microbial sulphate reduction was carried out in an anaerobic up-flow packed bed bioreactor (R1) using ethanol as carbon source. More than 90% of Total Equivalent Sulphate (TES) present in the effluent was reduced to sulphide at HRT of 17 h in the tested loading range of 0.58–3.10 kg SO4/m3/day. Mass balance revealed that more than 88% of sulphate reduced was present as dissolved sulphide (HS−) and while only 0.01% was present as H2S(g). The paper discusses the feasibility of converting both H2S(g) and HS− into value-added products such as elemental sulphur and metal sulphide nanoparticles, respectively. Since the amount of H2S generated is very low (0.01%), this paper also suggests recovery of dissolved sulphide from the R1 effluent, as transition metal sulphide nanoparticles.Int. J. Environment and Pollution. 01/2010; 43:129. -
Article: Development of a novel circular secondary clarifier for improving solids liquid separation in wastewater treatment.
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ABSTRACT: A novel circular secondary clarifier was developed to obviate the shortcomings of conventional clarifiers. The novel clarifier provides natural flocculation, which occurs as a result of hydraulic energy dissipation and the formation of sludge cloud referred to as plume. The efficiency of the clarifier depends on the stability of the plume, which in turn depends on the velocity gradient. For natural flocculation to occur, a velocity gradient of 10 to 15 s(-1) was found to be favorable. This velocity also keeps the plume-rise well below the free-surface. The mean particle size of mixed liquor suspended solids increases from 41 to 83 microm in the plume, which indicates agglomeration of particles and confirms that natural flocculation is occurring within the plume. The hydraulic improvement achieved by improving inlet design dissipates hydraulic energy, uniformly distributes flow, minimizes sludge blanket disturbances, and promote flocculation. The improved clarifier operates at 1-h hydraulic retention time.Water Environment Research 03/2009; 81(2):140-9. · 0.88 Impact Factor -
Article: Evaluation of monitoring sites for protection of groundwater in an urban area.
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ABSTRACT: Monitoring for seasonal variation and changes in groundwater is a costly project. Assessing groundwater at selected monitoring sites and for site-specific indicators may reduce the cost of subsequent monitoring. In this context, the present study developed a method to assess groundwater using a combination of multivariate and univariate statistical techniques to identify critical sites of contamination. The sample data used describes the groundwater quality in Allahabad, India. The factor analysis brings out the observable parameters for groundwater pollution. Finally, univariate techniques such as analysis of variance (ANOVA) and Bonferroni t-test identify the critical sites of groundwater pollution. The first factor indicated high loading (>0.6) of total dissolved solids, Cl, Na, Mg, conductivity, SO4, and hardness. This represented overall pollution status of groundwater from human habitation, waste disposal, and agricultural activities in Allahabad. Iron, Mn, and Zn showed loading on distinct factors and indicated local contamination. Univariate techniques ANOVA and Bonferroni t-test for Zn concentration in handpump samples revealed heavy metal contamination at Hasimpur and Beniganj in India. Thus, initial monitoring followed by statistical analysis can help identify critical sampling locations and important indicators.Water Environment Research 12/2008; 80(11):2157-64. · 0.88 Impact Factor -
Article: Steady state model for evaluation of external and internal mass transfer effects in an immobilized biofilm.
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ABSTRACT: A steady model for the evaluation of external liquid film diffusion and internal pore diffusion effects in an immobilized biofilm system under continuous mode of operation was developed. The model takes into account, substrate diffusion through external liquid film and biofilm. Average rate of substrate consumption in the biofilm was considered. The overall efficiency of the biofilm was mathematically represented by considering the combined effects of substrate penetration and substrate utilization in the biofilm. The model was illustrated using a case study of pyridine biodegradation in a rotating biological contactor immobilized with pyridine degrading microbial film. The model is able to effectively predict both internal and external mass transfer effects in an immobilized biofilm system.Bioresource Technology 07/2008; 99(9):3468-74. · 4.98 Impact Factor -
Article: Assessment of the status of municipal solid waste management in metro cities, state capitals, class I cities, and class II towns in India: an insight.
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ABSTRACT: Solid waste management is one of the most challenging issues in urban cities, which are facing a serious pollution problem due to the generation of huge quantities of solid waste. This paper presents an assessment of the existing situation of municipal solid waste management (MSWM) in major cities in India. The quantity and composition of MSW vary from place to place, and bear a rather consistent correlation with the average standard of living. Extensive field investigations were carried out for quantification, analysis of physical composition, and characterization of MSW in each of the identified cities. The MSW management status (per the MSW Rules, 2000) has also been assessed, and an action plan for better management has been formulated; both are presented in this paper. Studies carried out in 59 selected cities in India have revealed that there are many shortcomings in the existing practices used in managing the MSW. These shortcomings pertain mainly to inadequate manpower, financial resources, implements, and machinery required for effectively carrying out various activities for MSWM. To overcome the deficiencies in the existing MSWM systems, an indicative action plan has been presented incorporating strategies and guidelines. Based on this plan, municipal agencies can prepare specific action plans for their respective cities.Waste Management 07/2008; 29(2):883-95. · 2.43 Impact Factor -
Article: Multivariate analysis of groundwater resources in Ganga-Yamuna basin (India).
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ABSTRACT: Groundwater quality data on physico-chemical, bacteriological and heavy metal concentrations in three cities (Faridabad, Allahabad and Varanasi) in Ganga-Yamuna basin was subjected to multivariate analysis (MVA) using SPSS. The factors extracted showed high loading (> 0.3) of various parameters, such as Cl, conductivity, TDS, hardness, Na, Mg, and SO4, indicating contamination due to leaching of pollutants. Major manifest variable associated with these factors is the unorganized solid waste dumping practiced in all the cities. Bacterial contamination of hand pump samples in Allahabad is attributed to surface water-groundwater interaction. The factor with high loading of Ca and F is indicative of geological conditions of the region. Wells in Yamuna river sub-watershed exhibit less freshwater recharge, which is attributed to surface water pollution and sediment deposition in the river. Thus, the methodology for hydrogeological analysis is useful to identify critical water quality issues and possible sources of pollution in river basins.Journal of environmental science & engineering. 07/2008; 50(3):215-22. -
Article: Study of speciation of metals in an industrial sludge and evaluation of metal chelators for their removal.
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ABSTRACT: Leachability and mobility of metals were evaluated in sludge obtained from electroplating industry, using toxicity characteristic leaching procedure (TCLP) and diethylene triamine pentaacetic acid test (DTPA). Sequential leaching procedure was used to determine the chemical fractionation of metals. Further, removal of metals from sludge using various chelators (EDTA, citric acid, siderophore) was evaluated. The leaching test indicated that nickel in the sludge sample exceeded 5 ppm concentration. This categorized the sludge, as a toxic waste. The mobility of the metals in the sludge was in the following order: Ni, Fe, Zn, Cr, Pb. Metals were found to be associated with various fractions of sludge. The metal concentration in the sludge was very high as compared to normal abundance and thus not within the range to be used as a fertilizer. The low removal of metals from the sludge by various chelators may be due to overloading of metals and use of aged sludge rather than artificially contaminated one for the study. The results of this study bring forth the prospect of the use of siderophores for bioremediation, because it is biodegradable and ecofriendly. This can be achieved with further optimization of the method, exploration of more potent siderophores and by inclusion of metal bound sludge fraction specific treatments.Journal of Hazardous Materials 05/2008; 152(2):545-53. · 4.17 Impact Factor -
Article: Trends of organochlorine pesticides in drinking water supplies.
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ABSTRACT: The effectiveness of the treatment process for the removal of pesticides in the final water supplies in Delhi has been evaluated. Samples were collected during 2000-2005 from five water treatment plants (WTPs). Analysis was carried out to identify pesticides, which are more commonly encountered in treated drinking water. In most of the treatment plants, the concentrations of lindane, total endosulphan and total DDT were significantly less in the finished water. Monitoring of these less soluble pesticide in the finished water from WTPs was done quarterly to arrive at the quality trends and to plan for the mitigation action, in case the concentration of the parameter exceeded at any site or time.Environmental Monitoring and Assessment 03/2008; 137(1-3):295-9. · 1.40 Impact Factor -
Article: Chemical composition of major ions in rainwater.
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ABSTRACT: The present study investigated the chemical composition of rainwater at Kabir nagar, Nari, Nagpur, Maharashtra, India. The rainwater samples were collected on event basis during June-July-August-2006 and were analyzed for pH, major anions Cl, NO(3), SO(4)) and cations (Ca, Mg, Na, K, NH4). The pH value varied from 6.0 to 7.3 (avg. 6.3 +/- 0.3) indicating alkaline nature of rainwater. The pH of the rainwater was found well above the reference pH (5.6), showing alkalinity during the monsoon season. The average and standard deviation of ionic composition was found to be 98.1 +/- 10.6 micro eql(-1). The total anions contribute 45.1% and cations 54.9%, respectively to rainwater. Neutralization factors (NF) followed a sequence of NF(Ca) > NF(Mg) > NF(NH4) with factors of 1.1, 0.38 and 0.15 indicating the crustal components are responsible for neutralization of anions. The average ratio of (NO(3) + Cl)/SO(4) observed as 1.1 indicates that nitric and hydrochloric acid influences the acidity of rainwater. The ratio of NH(4)/NO(3) and NH(4)/SO(4) was observed as 0.68 and 0.34 indicate that the possible compounds which may predominate in the atmosphere are NH(4)NO(3) and (NH(4))(2)SO(4). Ionic correlation was established to identify sources of origin. A good correlation was seen between Ca and Mg (r = 0.95); suggesting the common occurrence of these ions from crustal origin. Similarly, the acidic ions SO(4) and NO(3) correlated well (r = 0.60) indicating their origin from similar sources. Other relatively significant correlations were observed between Ca and SO4 (r = 0.92), Mg and SO(4) (r = 0.83), Ca and NO(3) (r = 0.09), Ca and Cl (r = 0.34) and Mg and Cl (r = 0.31), and Mg and NO(3) (r = 0.71). The observed rainwater ratio of Cl/Na (1.1) is closer to that of seawater ratio (1.16) indicates fractionation of sea-salt and modifications by non-marine constituents as the site is 834 km away from the sea coast. The nss-Ca contribution was observed as 95.7% suggesting their crustal origin whereas nss-Mg and nss-K shows their contribution as 87.9% and 83.2% indicating influence of soil sources. The nss-SO(4) contributed as 87.4% shows anthropogenic origin.Bulletin of Environmental Contamination and Toxicology 03/2008; 80(3):242-6. · 1.02 Impact Factor -
Article: Studies on acidification in two-phase biomethanation process of municipal solid waste.
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ABSTRACT: Biomethanation of municipal solid waste (MSW) is a slow process and the yield of biogas is usually low. Enhancement of acidification is necessary to increase the biogas yield in biomethanation of MSW. MSW contains a significant fraction of ligno-cellulosic material. The acidification of these materials influences the biogas yield. In the present study, hydrolysis and acidification have been considered as a combined phase. Experiments have been conducted to study the effect of recirculation of leachate on the acidification stage of the two-phase biomethanation process. Chemical oxygen demand (COD) and volatile fatty acid (VFA) were considered as indicator parameters. The study was also conducted to investigate the effect of using acid and alkali solution of 0.1% concentration in the acidification study. It was observed that daily recirculation of leachate does not have any major impact on the acidification process. It was also observed that treatment of MSW with sodium hydroxide yields leachate of significantly higher COD and VFA values compared to others.Waste Management 02/2008; 28(1):164-9. · 2.43 Impact Factor -
Article: Dynamic weighting system for water quality index.
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ABSTRACT: Water quality standards are developed world over by National and International agencies for pollution control decision-making. Use-based water quality classification criteria and Water Quality Indices (WQIs) also play important role in assessment of water resources for their suitability with reference various uses. Formulation of value function curves and weights assigned to parameters in WQIs are often defined by local water experts and hence WQIs are known to inherit subjectivity. Assignment of weights a priori to various water quality parameters results in misclassification of water quality by WQI. A method of dynamic weighting has been developed in the present work to assign weights to water quality parameters with due consideration to their pollution effect at a particular site. Application of a methodology to Overall Index of Pollution (OIP) provides water quality classification of Indian rivers as "Polluted", "Acceptable", and "Slightly Polluted", which is comparable with the reported CPCB classification as well as with the statistical index CCME-WQI. The methodology developed is general and can be applied to any subjective index. This is exemplified by dynamically weighting the parameters in NSF-WQI for Red and Waikato rivers. Dynamic weighting system provides a true representation to comprehend water quality classification and to achieve River Quality Objectives.Water Science & Technology 02/2008; 58(6):1261-71. · 1.12 Impact Factor -
Article: GIS-based locational analysis of collection bins in municipal solid waste management systems
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ABSTRACT: Solid waste management systems currently receive wide attention, from both economic and environmental plan-ners, because of their complexity during coordination of various management strategies. The efficiency and cost effective-ness of route optimization and disposal site selection depend largely upon the appropriate placement of storage bins and their corresponding command area for waste contribution. The present paper illustrates a geographic information system (GIS) based algorithm for optimal location and number of storage bins, considering p-median constrained model, based on Indian guidelines for Municipal Solid Waste Rules. The algorithm also computes the contributing command area of solid waste to a particular bin, based on the shortest distance, with descending slope for ease in solid waste collection. Résumé : Les systèmes de gestion des déchets solides attirent présentement beaucoup l'attention des planificateurs écono-miques et environnementaux en raison de leur complexité durant la coordination de diverses stratégies de gestion. L'effi-cacité et la rentabilité de l'optimization de route et la sélection du site d'enfouissement dépendent en grande partie de l'emplacement approprié des bacs de stockage et leur zone desservie correspondante pour la collecte de déchets. Le pré-sent article présente un algorithme basé sur un système d'information géographique (SIG) utilisé pour déterminer l'empla-cement et le nombre optimaux de bacs de stockage, compte tenu d'un modèle p-médian contraint, basé sur les directives concernant la réglementation des déchets solides municipaux en Inde. L'algorithme calcule également la zone de collecte de déchets solides desservie par un bac de stockage particulier en se basant sur la plus courte distance, avec une pente des-cendante pour faciliter la collecte des déchets solides. Mots-clés : déchets municipaux solides, emplacement des bacs, zone desservie, système d'information géographique. [Traduit par la Rédaction]Journal of Environmental Engineering and Science 01/2008; · 0.94 Impact Factor -
Article: Simulation of impact of oil spill in the ocean--a case study of Arabian Gulf.
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ABSTRACT: To meet the growing energy demand worldwide, oil and gas exploration and production activities have increased rapidly both in onshore and offshore areas. The produced oil from the ocean bed is transported onshore either by ship or pipeline. This has increased the risk of oil spill in the coastal area. In order to prepare an emergency preparedness plan and to assess the magnitude of risk involved in transporting and offloading oil, oil spill simulation studies play an important role. This paper describes a simulation of oil spill in coastal bay of Arabian Gulf where new developments are taking place using MIKE 21 model. The developments include a diesel based thermal power plant near Sir Baniyas Island, which is an ecological fragile area. Based on the project activity, two probable scenarios, one for diesel leak (250 m3/h) for 1 h and the other for instantaneous spill (500 m3) are considered. The MIKE 21 model was calibrated for hydrodynamics using measured field data followed by diesel-spill simulation to track its movement in the Arabian Gulf. The results for both leak and instantaneous spill indicate that spilled diesel will not move towards the Sir Banyas Island and more than 45% of the diesel will be evaporated within 48 h of oil spill. Based on the results, a clean up and contingency plan is proposed to mitigate the adverse impacts arising due to diesel spill in the study area.Environmental Monitoring and Assessment 01/2008; 146(1-3):191-201. · 1.40 Impact Factor -
Article: Hazardous Waste Management System in India: An Overview
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ABSTRACT: Lack treatment and disposal facilities causes hazardous wastes (HWs) to ravage municipal landfills and open spaces, raising serious environmental threats. Rapid industrialization over the last few decades has indiscriminately increased HW generation in India. In March 2000, the total HW generated was estimated to be 4.41 metric million tonnes (Babu and Ramkrishna, 20035. Babu , B. V. and Ramakrishna , V. 2003 . Extended studies on mathematical modeling of site sensitivity indices in the site selection criteria for hazardous waste treatment, storage and disposal facility . Journal of the Institution of Public Health Engineers India , : 11 – 17 . http://bvbabu.50megs.com/custom.html/#43,2003 Also available as pdf file at View all references). Adding to this woe are the substantial quantities of HWs being imported for recycling. Large quantities of HWs generated include used batteries, used and waste oil, broken fluorescent lamps, cleansing chemicals for wastes, pesticides past their expiration dates, and so forth. There are only a few well-established treatment, storage, and disposal facilities (TSDF), which precludes effective enforcement of regulations for HW generated from the industrial or nonindustrial sector. The guidelines issued by the Ministry of Environment and Forests (MoEF), Government of India, and the Central Pollution Control Board (CPCB) are available for selection of the best sites for TSDF and for establishing secured landfills (MoEF Guidelines, 1989, as amended in 2003). Only Gujarat, Maharashtra, and Andhra Pradesh states have TSDFs, though not in sufficient numbers and sizes to cater to the entire quantity of HWs generated (Babu and Ramkrishna, 20035. Babu , B. V. and Ramakrishna , V. 2003 . Extended studies on mathematical modeling of site sensitivity indices in the site selection criteria for hazardous waste treatment, storage and disposal facility . Journal of the Institution of Public Health Engineers India , : 11 – 17 . http://bvbabu.50megs.com/custom.html/#43,2003 Also available as pdf file at View all references). This article focuses on the current status, problems and challenges, policy issues, and future strategies for improvement in HW management system in India.Critical Reviews in Environmental Science and Technology 01/2008; 38(1):43-71. · 4.84 Impact Factor -
Article: Indoor air quality of public places in Mumbai, India in terms of volatile organic compounds.
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ABSTRACT: Indoor air quality at nine locations viz. food courts, restaurant, bar, conference room, office and theater, which can be classified as public places have been monitored for Volatile Organic Compounds (VOCs) content. Forty VOCs have been identified and one fourth of these are classified as Hazardous Air Pollutants. Levels of most VOCs are observed to be below the guideline values for public places and offices, as adopted by Hong Kong. Consumer goods are found to be predominant source of chlorinated VOCs in indoor air. Levels of benzene and carbon tetrachlorides were observed to be above the guideline values at all the locations. Effect of ozonisation on Total VOC concentrations have also been studied.Environmental Monitoring and Assessment 11/2007; 133(1-3):127-38. · 1.40 Impact Factor -
Article: Biosurfactant technology for remediation of cadmium and lead contaminated soils.
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ABSTRACT: This research focuses on column experiments conducted to evaluate the potential of environmentally compatible rhamnolipid biosurfactant produced by Pseudomonas aeruginosa strain BS2 to remove heavy metals (Cd and Pb) from artificially contaminated soil. Results have shown that di-rhamnolipid removes not only the leachable or available fraction of Cd and Pb but also the bound metals as compared to tap water which removed the mobile fraction only. Washing of contaminated soil with tap water revealed that approximately 2.7% of Cd and 9.8% of Pb in contaminated soil was in freely available or weakly bound forms whereas washing with rhamnolipid removed 92% of Cd and 88% of Pb after 36 h of leaching. This indicated that di-rhamnolipid selectively favours mobilization of metals in the order of Cd>Pb. Biosurfactant specificity observed towards specific metal will help in preferential elution of specific contaminant using di-rhamnolipid. It was further observed that pH of the leachates collected from heavy metal contaminated soil column treated with di-rhamnolipid solution was low (6.60-6.78) as compared to that of leachates from heavy metal contaminated soil column treated with tap water (pH 6.90-7.25), which showed high dissolution of metal species from the contaminated soil and effective leaching of metals with treatment with biosurfactant. The microbial population of the contaminated soil was increased after removal of metals by biosurfactant indicating the decrease of toxicity of metals to soil microflora. This study shows that biosurfactant technology can be an effective and nondestructive method for bioremediation of cadmium and lead contaminated soil.Chemosphere 08/2007; 68(10):1996-2002. · 3.21 Impact Factor -
Article: Dioxin formation in pulp and paper mills of India.
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ABSTRACT: Samples of effluents, sludge, pulp, final products (paper) and soil were collected from the identified pulp and paper mills in India. The samples were analysed for 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and other dioxin congeners and precursors. Pulp and paper mills using chlorine for the bleaching process showed the presence of 2,3,7,8-TCDD in effluent samples. In the effluent and pulp samples from mills where chlorine dioxide was used as a bleaching agent, the 2,3,7,8-TCDD congener ranged from below the detection limit 0.05 to 0.12 ngL(-1)/ngg(-1). The relative standard deviation of reproducibility and the percent recovery of 2,3,7,8-TCDD were 2.07 and 82.4% in pulp and 2.8 and 92% in effluent, respectively. The 1,3,6,8-TCDD was the only other major dioxin congener found in the treated and untreated effluent and sludge samples. However, dichlorobenzene, trichlorophenyl, and hexachlorobiphenyl were detected in all samples. The formation of dioxins can be minimised by replacing chlorine with chlorine dioxide in bleaching processes in pulp and paper mills.Environmental Science and Pollution Research 07/2007; 14(4):225-6. · 2.65 Impact Factor -
Article: Air quality assessment in Delhi: before and after CNG as fuel.
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ABSTRACT: A number of policy measures have been activated in India in order to control the levels of air pollutants such as particulate matter, sulphur dioxide (SO(2)) and nitrogen dioxide (NO(2)). Delhi, which is one of the most polluted cities in the world, is also going through the implementation phase of the control policies. Ambient air quality data monitored during 2000 to 2003, at 10 sites in Delhi, were analyzed to assess the impact of implementation of these measures, specifically fuel change in vehicles. This paper presents the impact of policy measures on ambient air quality levels and also the source apportionment. CO and NO(2) concentration levels in ambient air are found to be associated with the mobile sources. The temporal variation of air quality data shows the significant effect of shift to CNG (Compressed Natural Gas) in vehicles.Environmental Monitoring and Assessment 03/2007; 125(1-3):257-63. · 1.40 Impact Factor -
Article: Surfactant-modified zeolite as a slow release fertilizer for phosphorus.
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ABSTRACT: The feasibility of using surfactant-modified zeolite (SMZ) as a carrier for fertilizer and for slow release of phosphorus (P) was investigated. Zeolite-A was modified by using hexadecyltrimethylammonium bromide, a cationic surfactant, to modify its surface to increase its capacity to retain anion, namely, phosphate (PO4(3-)). SMZ was thoroughly characterized using X-ray diffraction, Fourier transform infrared, and scanning electron microscopy to study the effect of surfactant modification. Zeolite-A and SMZ were then subjected to P loading by treating them with fertilizer (KH2PO4). It was observed that the P loading on SMZ increased by a factor of 4.9 as compared to the unmodified zeolite-A. A comparative study of the release of P from fertilizer-loaded unmodified zeolite-A and SMZ and from solid KH2PO4 was performed using the constant flow percolation reactor. The results show that the P supply from fertilizer-loaded SMZ was available even after 1080 h of continuous percolation, whereas P from KH2PO4 was exhausted within 264 h. The results indicate that SMZ is a good sorbent for PO4(3-), and a slow release of P was achievable. These properties suggest that SMZ has a great potential as the fertilizer carrier for slow release of P.Journal of Agricultural and Food Chemistry 07/2006; 54(13):4773-9. · 2.82 Impact Factor -
Article: Application of supported perovskite-type catalysts for vehicular emission control
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ABSTRACT: Catalytic control of auto-exhaust emissions is one of the most successful applications of heterogeneous catalysis, both in commercial and environmental point of views. Although noble metal-based catalysts have dominated this area, efforts were always put in towards development of low cost non-noble metal-based catalysts. With the recent need of closed-coupled catalytic converter, thermal stability requirements have also become more severe, leading to the search for stable catalytic materials. Mixed oxides, including those perovskite type compounds with ABO3 structure have been extensively studied, mainly for their catalytic and electrical properties. Low surface area of these catalysts has so far been the most important limitation for their catalytic applications involving high space velocities, e.g. auto-exhaust catalysis. Various synthesis routes have been earlier attempted to improve their surface area, yet this was much inferior than the noble metal catalysts, dispersed on high surface area alumina. The in situ synthesis of these oxides on alumina is often associated with the formation of undesired phases, due to the reactive nature of perovskite precursors. However, alumina washcoat, commonly used for improving the surface area of ceramic and metallic catalyst supports, can be modified for perovskite applications. In situ synthesis of stabilized perovskites on modified alumina-washcoated supports offer high surface area and excellent catalyst adhesion. Although, it is difficult to ascertain the presence of pure perovskite type materials on support, such improved synthesis has resulted in remarkable improvement in their catalytic activity for their applications in auto-exhaust catalytic converters. This review presents our work on synthesis of various improved perovskite-type mixed oxides supported on modified alumina-washcoated cordierite honeycomb, their characterization, and detailed catalytic evaluations for possible application in automobile pollution control.Catalysis Surveys from Asia 02/2006; 10(1):55-64. · 1.90 Impact Factor
Top co-authors
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Institutions
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2005–2009
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National Environmental Engineering Research Institute
- Environmental System Design and Modelling Division (NEERI)
Nāgpur, State of Maharashtra, India -
IIT Kharagpur
- Department of Civil Engineering
Kharagpur, Bengal, India
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