Browsing by Author "Bhunia P."

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Applicability of a new pre-hydrated industrial grade polyaluminium salt for the decolourisation of textile wastewater
(2014) Verma A.K.; Bhunia P.; Dash R.R.
This study was conducted to assess the decolourisation and chemical oxygen demand (COD) reduction efficiency of a novel pre-hydrated aluminium salt as aluminium chlorohydrate (ACH) for the treatment of textile wastewater using coagulation/flocculation technology. Though, ACH belongs to the same group of polyaluminium salts, it is significantly different from polyaluminium chloride (PACl) in terms of the degree of hydration and alumina content and was used for the first time as a coagulant for the decolourisation of synthetic as well as real textile wastewater. The experimental results revealed that ACH is highly effective for the treatment of synthetic textile wastewater producing more than 99% of colour removal and 45% of COD reduction efficiency at a very low dosage of 200mgL-1. The decolourisation of real textile wastewater was found to be very much in line with the results obtained for the treatment of synthetic textile wastewater. Superior decolourisation efficiency at a very low dosage as compared to that of the pre-established studies for real textile wastewater and least volume of easily dewatered sludge production makes ACH a novel and very promising coagulant for the treatment of industrial textile wastewater. � 2013 Balaban Desalination Publications. All rights reserved.
Application of ultrasonication and hybrid bioreactor for treatment of synthetic textile wastewater
(2017) Verma A.K.; Nath D.; Bhunia P.; Dash R.R.
This study explores the influence of ultrasonic pretreatment on the performance of a hybrid bioreactor treating synthetic textile wastewater. The study primarily focuses on assessing the decolorization and chemical oxygen demand (COD) reduction efficiency of a hybrid bioreactor. The hybrid bioreactor provided anaerobic-aerobic sequential treatment to the ultrasonically pretreated textile wastewater containing two new generation diazo dyes namely, reactive black 5 (RB5) and reactive red (RR120), along with other chemical constituents. Ultrasonic pretreatment produced approximately 52% color and 48% COD reduction efficiency at an optimized power of 200 W and 180 min sonication time. For the hybrid reactor treating ultrasonically pretreated textile wastewater, a maximum of 98% COD and 92% color removal efficiencies were obtained at an HRT of 32 h [organic loading rate (OLR)=0.74 kg COD m-3d-1] and 24 h (OLR=1.0 kg COD m-3 d-1), respectively. Significant levels of aromatic amines formation were observed in the anaerobic phase. However, those were effectively eliminated in the subsequent aerobic phase inside the hybrid bioreactor. Volatile fatty acids to bicarbonate alkalinity (VFA/B-alk.) ratios, one of the health indicators of the bioreactor operation, were found in the range of 0.23-0.32 at different hydraulic retention times (HRTs), thus indicating the adequate buffering capacity for stability of the bioreactor. The study demonstrates the importance of ultrasonic pretreatment for mineralizing organic and inorganic impurities present in textile wastewater, which significantly improves the performance of subsequent hybrid bioreactor. � 2016 American Society of Civil Engineers.
Assessing possible applications of waste organic solid substances as carbon sources and biofilm substrates for elimination of nitrate toxicity from wastewater
(2017) Rout P.R.; Bhunia P.; Dash R.R.
This work aimed to find inexpensive alternatives that could serve both as carbon source and biofilm carrier for heterotrophic denitrification in treating nitrate contaminated waters. To ascertain cost efficiency, the effectiveness of four different waste organic solid substances (WOSS) like sugarcane bagasse (SB), coconut shell (CS), aegle shell (AS), groundnut shell (GS), and the equal-volume mixture of all (Mix) were assessed in batch experiments. Subsequently, the best performing (Mix) substrate was evaluated in column mode of experiments under different experimental conditions and the optimized values were verified as bed depth of 30-40 cm, hydraulic retention time (HRT) of 24-26 h, and flow rate of 1.5 mL/min. In optimum conditions, real domestic wastewater was successfully denitrified over a period of 2 months. The first-order reaction with R2 in the range of 0.96-0.99 better described the denitrification process both in batch and column studies. Mix substrate further contributed to a speedy establishment of active denitrifying consortia consisting of Stenotrophomonas, Bacillus, and Ochrobactrum as the dominant genuses. The study validated the possible application of the selected Mix substrate as a potential substrate for biological denitrification process.
Carbonaceous organics removal kinetics in an upflow anaerobic sludge blanket (UASB) reactor treating physico-chemically pre-treated textile wastewater
(2015) Verma A.K.; Bhunia P.; Dash R.R.
In the present study, physico-chemically pre-treated textile wastewater with a residual chemical oxygen demand (COD) of 780 � 10 mg L?1 was treated using a lab-scale upflow anaerobic sludge blanket (UASB) reactor at variable HRTs of 30.8 to 8 h, and organic loading rates (OLRs) of 0.62�2.4 kg COD m?3 d?1. Using a new composite coagulant at dosage of 800 mg L?1 for pre-treatment, more than 99% of colour was removed from the feeding influent to UASB reactor. The optimum OLR was found as 0.95 kg COD m?3 d?1 at which maximum COD reduction (98%) was achieved. Modified Stover-Kincannon, Grau second-order, Monod, Haldane and Contois models were applied to evaluate the carbonaceous substrate removal kinetics inside the UASB reactor. The experimental results of this analysis revealed that modified Stover-Kincannon and Grau second-order kinetics were suitable for predicting the performance and to estimate the kinetic coefficients of UASB reactor. � 2014, � 2014 Balaban Desalination Publications. All rights reserved.
COD removal index � A mechanistic tool for predicting organics removal performance of vermifilters
(2018) Singh R.; Bhunia P.; Dash R.R.
The present study was aimed at developing a mathematical COD removal index (CRI) based on the key variables of vermifiltration such as hydraulic retention time (HRT), organic concentration and earthworm density (EWD). In the maiden attempt of framing such an index, many experimental runs were conducted by varying the COD strength of the wastewater from 2.0�4.0 kg/m3, EWD and HLR were from 0 to 10,000 earthworms/m3 and 1.8�4.5 m3/m2�d, respectively. The sensitivity analysis of the developed CRI reveals that the EWD, bedding volume, concentration of organics and the flow applied to the vermifilter can immensely affect the model response. However, flow applied to the system is observed to be the most sensitive among other parameters incorporated in the model. In addition, from the sensitivity analysis, it was also revealed that the removal efficiencies were observed to increase with the increase in CRI values in the COD range of 0.2�6.0 kg/m3. In addition, the plot between the reported removals from literatures on vermifiltration of domestic wastewater and CRI values yielded an R2 value of 0.76. Such a high correlation suggests that the developed CRI index can be applied for other wastewaters also. The results of this study indicate that the developed index can successfully be applied in determining and predicting organics removal from vermifiltration of wastewaters. � 2018 Elsevier B.V.
A comparative study of macrophytes influence on performance of hybrid vermifilter for dairy wastewater treatment
(2018) Samal K.; Dash R.R.; Bhunia P.
Population increase and speedy urbanization are two major driving factors for scarcity of water in present time. To fulfil such water demand, reuse of industrial wastewater is necessary after essential purification. Vermifilter coupled with macrophyte filter is one of the promising technology for the treatment of organics and nutrient rich wastewater. In the present study, various macrophytes have been planted in vermifilter to study their effect on pollutants removal efficiency. Four sets of reactors R1, R2, R3 and R4 were designed and each set of reactor consisted of two units: vertical flow (VF) and horizontal flow (HF) unit. R1, R2 and R3 were planted with Canna indica, Saccharum spontaneum and Typha angustifolia, respectively, whereas R4 was without any macrophyte. Earthworm Eisenia fetida was inserted in all the four reactors. VF units of all hybrid vermifilter were loaded with synthetic dairy wastewater at hydraulic loading rate (HLR) of 0.6�m d-1. Effluents were collected at the bottom of the VF unit and channelled to the HF unit. Final effluent was collected at the end of the HF unit. The order of average percentage removal of COD was R1 (82.8%) > R3 (78.9%) > R2 (75.5%) > R4 (69.4%). Organics and nutrients were targeted to remove in the filter as these pollutants make major fraction in real dairy wastewater compare to antibiotics and other emerging contaminants. Presence of very few kind and low amount of antibiotics in dairy wastewater like lincomycin, chlortetracycline, etc. have been reported in literature. � 2018 Elsevier Ltd. All rights reserved.
Design and development of a hybrid macrophyte assisted vermifilter for the treatment of dairy wastewater: A statistical and kinetic modelling approach
(2018) Samal K.; Dash R.R.; Bhunia P.
Global urbanization, exponential increase in population and sophisticated life style of the present generation are the major causes leading to a rapid increase in water demand in recent years. In order to nullify this rising water demand, it's high time to reuse domestic as well as industrial effluent after providing suitable chemical/biological treatment. Macrophyte filter incorporated with earthworm is identified as one of the most economic system for the treatment purpose in developing countries. However, very few literatures and technical information are available to scale up the design and its easy operation. This paper aims to develop a hybrid system and assess its performance for the purification of dairy wastewater. In the present study, two stage macrophyte assisted vermifilters (MAVFs) have been designed. The 1st stage encompassed a vertical flow (VF) unit, and the 2nd stage contained a horizontal flow (HF) unit. Both the units were inoculated with earthworm Eisenia fetida and were planted with Canna indica. Box-Behnken model was applied to design the system and study the effect of various parameters. It was observed that hybrid MAVF system removed a maximum of 83.2% COD and 57.3% TN at HLR 0.6 m/d and an active layer depth of 30 cm. Ammonification and nitrification typically occurred in the active layer (earthworm inoculated zone) of VF unit due to high activity of earthworms and its associated gut microbes, whereas HF unit facilitate denitrification process. Earthworm growth characteristics in the system were monitored, which is an imperative factor for the design of MAVF reactor. Kinetic modelling of 1st order, grau 2nd order and Stover-Kincannon model were performed and the Stover-Kincannon model showed high regression coefficient (COD, R2 0.9961 and TN, R2 0.9353) supporting its applicability as compared to the other models. � 2018
Development of an integrated system for the treatment of rural domestic wastewater: Emphasis on nutrient removal
(2016) Rout P.R.; Dash R.R.; Bhunia P.
With the aim of enhancing the nutrient removal from rural domestic wastewater while reducing the cost of the treatment process, a novel, integrated treatment system consisting of a multi-stage bio-filter with drop aeration and a post positioned attached growth carbonaceous denitrifying bio-reactor was designed and developed in this study. The bio-filter was packed with 'dolochar', a sponge iron industry waste, as an adsorbent mainly for phosphate removal through a physicochemical approach. The denitrifying bio-reactor was packed with many waste organic solid substances (WOSS) as carbon sources and substrates for biomass attachment, mainly to remove nitrate in the biological denitrification process. The performance of the modular system, treating real domestic wastewater was monitored for a period of about 60 days and the average removal efficiencies during the period were as follows: phosphate, 99.48%; nitrate, 92.44%, ammonia, 96.64%, with mean final effluent concentration of 0.153, 5.5, and 1.06 mg L-1, respectively. This treatment system would allow multipurpose reuse of the final effluent. Moreover, the saturated dolochar can be used as a nutrient supply in agricultural practices and the partially degraded carbonaceous substances can also be used as an organic fertilizer after composting. Thus, the system displays immense potential for treating domestic wastewater significantly by decreasing the concentrations of nutrient and most importantly, facilitating the conversion of the waste materials into usable ones. � 2016 The Royal Society of Chemistry.
Effect of hydraulic loading rate and pollutants degradation kinetics in two stage hybrid macrophyte assisted vermifiltration system
(2018) Samal K.; Dash R.R.; Bhunia P.
Three cylindrical vertical flow (VF) (1st stage) and three horizontal flow (HF) vermifilters (2nd stage) were designed and planted with Canna indica to study the effect of HLR. The vermifilters were loaded (to VF) with synthetic dairy wastewater at three HLRs of 0.3, 0.6 and 0.9 m d?1 and operated for 100 days. Removal rate constants were higher at HLR 0.6 m d?1 and the value of KBOD5, KCOD, KNH4+-N, KTN, KTP (for VF + HF unit) were 0.51, 0.41, 0.32, 0.23, 0.26, respectively. Efficiency of VF reactor were higher than HF reactor in case of all types of pollutants. The average removal of BOD5 was found to be 90.43% at HLR 0.3 m d?1 and 85.75% at HLR 0.6 m d?1, while for COD it was found to be 85.59% and 79.64%, respectively. In the present study, the overall theoretical oxygen transfer rate (OTR) for HLR 0.3, 0.6 and 0.9 m d?1 (VF + HF unit) were 36, 92 and 195.6 g m?2 d?1, respectively. The OTR value for HF reactor was very less. The present value is much higher than other studies and it may be due to earthworm respiration and their burrowing and tunnelling activities. The percentage increase of earthworm number in all VF reactors were in the range of 28.3�31.5 and in HF reactor in the range of 19.1�26.2. � 2018 Elsevier B.V.
Effective utilization of a sponge iron industry by-product for phosphate removal from aqueous solution: A statistical and kinetic modelling approach
(2015) Rout P.R.; Bhunia P.; Dash R.R.
Dolochar, a solid waste generated from sponge iron industry during the process of direct reduction of iron by rotary kiln, is explored as an adsorbent for phosphate removal in this study. The depiction of the adsorption process was done by X-ray diffraction (XRD), Fourier transferred infra-red spectroscopy (FTIR), and Energy dispersive spectroscopy (EDS) analysis. The appearance of phosphorous peak in EDS spectra of spent dolochar confirmed phosphate adsorption. Application of response surface methodology (RSM) and analysis of variance (ANOVA) for modelling and optimization of phosphate removal in batch study and breakthrough time in column study, suggested quadratic models for both the responses. Experimental validation of the optimization process resulted in 98.13% phosphate removal and 24.67h breakthrough time. Pseudo second order kinetic and Langmuir isotherm illustrated best fit to the experimental data with R2=0.98 and R2=0.99, respectively. The values of separation factor (1>RL>0), Freundlich exponent (n>1) and thermodynamic parameters (?G�, -3442.6kJ/mol and ?H�, 6627kJ/mol) specified favourable spontaneous and endothermic adsorption process. The adsorbent displayed 80% of the original adsorption capacity in the 3rd cycle of reuse. The results of this study support the utility of dolochar as a low cost and highly efficient adsorbent for phosphate removal from aqueous solution. � 2014 Taiwan Institute of Chemical Engineers.
Effectiveness of aegle shell (AS) and groundnut shell (GS) as carbon sources for bio-denitrification of nitrate rich aqueous solution
(2016) Rout P.R.; Dash R.R.; Bhunia P.
Many of the waste organic solid substances (WOSS) can be biologically degraded into smaller organic molecules that in turn can be used by the microbial community as carbon and energy sources. The attempt of this work aims at making the organic sources available to the denitrifying biomass, which in turn helps in removing nitrates from aqueous solution. In this study we have explored the effectiveness of many WOSS like sugarcane baggage (SB), coconut shell (CS), aegle shell (AS), groundnut shell (GS) etc. as carbon source and substrate for biomass attachment in biological denitrification process. Among the examined substances, AS and GS responded effectively both to the batch and continuous mode of denitrification experiments. The results of the batch test showed the denitrification efficiency to be 98% and 96.5%, while that of soluble chemical oxygen demand (SCOD) utilization being 87% and 97%, respectively for AS and GS. There was negligible amount of accumulation of nitrite and ammonium ions in both the cases. In continuous experiments the denitrification efficiency for AS and GS were found to be 98.5% and 96%, respectively. Negligible amounts of nitrite and ammonium accumulation and 100% SCOD utilization were other findings of continuous experiments. The results of this study advocates for the possible application of AS and GS, as carbon sources and substrates for biomass attachment in biological denitrification process. � 2016 American Scientific Publishers. All rights reserved.
Effectiveness of aluminum chlorohydrate (ACH) for decolorization of silk dyebath effluents
(2012) Verma A.K.; Bhunia P.; Dash R.R.
The present study focuses on the decolorization of real silk dyebath effluents using analytical-grade magnesium chloride (MCl) with and without guar gum (GG) as a coagulant aid and industrial-grade polyaluminium chloride (PACl) and aluminum chlorohydrate (ACH) as coagulants. A higher decolorization efficiency of 97% at a very high dosage of 1800 mg L -1 was observed for MCl. However, considering the purity, dosage, decolorization efficiency, and quantity and quality of sludge production, ACH was found to be the best coagulant, giving 91% decolorization efficiency at a dose of just 100 mg L -1. To achieve this high degree of decolorization efficiency, the dosage for PACl was found to be approximately 50% higher than that of ACH. Effective decolorization (>90%) at a very low dosage (100 mg L -1) and minimal quantity of sludge production by ACH demonstrate that ACH is an effective coagulant for decolorization of silk dyebath effluents. � 2012 American Chemical Society.
Effects of physico-chemical pre-treatment on the performance of an upflow anaerobic sludge blanket (UASB) reactor treating textile wastewater: Application of full factorial central composite design
(2015) Verma A.K.; Bhunia P.; Dash R.R.; Tyagi R.D.; Surampalli R.Y.; Zhang T.C.
The aim of this work was to study the influence of the pre-treatment step, influent chemical oxygen demand (COD), and hydraulic retention time (HRT) on the decolourization and COD removal efficiency of the upflow anaerobic sludge blanket (UASB) reactors for treating textile wastewater. Statistical models were formulated based on these three variables to optimize the decolourization and COD removal efficiency in the UASB reactor using a full factorial central composite design. The high correlation coefficients (R2=0.99) and the low p-values (?0.0001) reveal that the models and model terms are significant, which can be used to optimize the operational variables in an adequate way for the prediction of response variables. The COD removal efficiency of 70% and decolourization efficiency of 81% were observed for real textile wastewater treatment by UASB reactor without pre-treatment. Whereas for pre-treated real textile wastewater, these were 95% and 100%, respectively. The pre-treatment using a pre-investigated composite coagulant (MC+ACH) was vital in the overall treatment efficiency of the UASB reactor. Validation of model predictions for the treatment of synthetic and real textile wastewaters reveals the efficacy of these models for enhancing the decolourization and COD removal efficiency. � 2015 Canadian Society for Chemical Engineering.
Erratum: Nutrient removal from binary aqueous phase by dolochar: Highlighting optimization, single and binary adsorption isotherms and nutrient release (Process Saf. Environ. Prot. 100 (2016) 91-107 10.1016/j.psep.2016.01.001)
(2016) Rout P.R.; Dash R.R.; Bhunia P.
[No abstract available]
Evaluation of kinetic and statistical models for predicting breakthrough curves of phosphate removal using dolochar-packed columns
(2017) Rout P.R.; Bhunia P.; Dash R.R.
The sustainability in utilizing dolochar packed columns under dynamic conditions for phosphate removal from aqueous solutions, has been carried out in this study. The assessment of efficacy of the bed under varying experimental conditions of bed depth, flow rate and influent phosphate concentration revealed that, an increase in bed depth and initial phosphate concentration or a decrease in flow rate resulted in increased breakthrough and exhaustion time. Thomas, modified dose response (MDR) and Clark models were applied to simulate the experimental breakthrough curves following nonlinear regression analysis. Also bed depth service time (BDST) model was engaged to scale up the adsorption process by means of linear regression approach. All the models with a very high coefficient of correlation (R2�>�0.93) predicted the breakthrough curves equally well. Good consistency was observed among experimental bed adsorption capacity (8.56�mg�g?1) and those predicted by Thomas (9.21�mg�g?1) and MDR models (8.81�mg�g?1). Statistical modeling proposed quadratic models for breakthrough and exhaustion time, with R2 values of 0.99 in both the cases. Soil column analytical test confirms slow release of phosphate from spent dolochar. The results confirm the sustainable application of dolochar packed columns for phosphate abatement in large scale accompanied by the utilization of spent dolochar as a source of phosphate. � 2017 Elsevier Ltd
Fundamentals of Biological Treatment
(2014) Bhunia P.
This chapter provides important information on the fundamentals and engineering aspects of biological wastewater treatment. Understanding the behavior of the naturally occurring microorganisms and their biochemical reactions plays a vital role in the successful design and operation of biological wastewater treatment plants. With proper analysis and design, almost all wastewaters containing biodegradable organics can be treated biologically. The main objectives of this chapter are to (1) give an overview of the biochemical reactions, (2) classify the different types of microorganisms, (3) establish different aspects of microbial metabolism, (4) understand the stoichiometry and energetics of bacterial growth, (5) establish comprehension of the bacterial growth kinetics, and (6) to introduce the role of environmental factors influencing the different biological processes. The methods used to describe and solve the problems presented are those used by biochemical engineers, based on mass balances that are valid for specific systems. � 2014 Elsevier Inc. All rights reserved.
Impact of organic loading rate and earthworms on dissolved oxygen and vermifiltration
(2019) Singh R.; Bhunia P.; Dash R.R.
In order to facilitate an affordable, sustainable, and technologically viable alternative to traditional brewery wastewater remediation technologies, vermifiltration was explored in this study. The impacts of high organic loading rates (OLRs) on removal of organics and nutrients from a vermifilter and their relationship with earthworm inoculation rates were the principal focus. The current study also investigated the role of dissolved oxygen (DO) in vermifiltration. To conduct this study, OLRs ranged 2.25-11.25 kgCOD=m 3 � d, while earthworm numbers varied 0-10,000 perm 3 . The average effluent DO was in the range 0.8-0.9 mg=L from biofilters and 1.5-2.1 mg=L from vermifilters. A chemical oxygen demand (COD) removal efficiency of 92%-96% and a NH 4 + -N conversion efficiency of 81%-85% were observed when OLRs ranged 2.25-3.15 kgCOD=m 3 � d and earthworm density (EWD) ranged 5,000-10,000 � NO 3 - -N generation was also observed to be in parity with NH 4 + -N conversion from the system. The impact of DO on COD removal, nitrification, and denitrification was found to be significant. A maximum total nitrogen (TN) removal efficiency of 24% was observed at an EWD of 10,000. Unlike nitrogen removal, phosphorous removal was mostly dependent on adsorption due to dolochar and fine soil particles produced by earthworms. Maximum removal efficiencies of 61% and 44% were observed for PO 4 3- -P and total phosphates (TP), respectively. The results obtained indicate that DO plays a crucial role in vermifiltration and that EWD and OLR play pivotal roles in maintaining DO in the effluents obtained from vermifiltration. � 2019 American Society of Civil Engineers.
A mechanistic approach to evaluate the effectiveness of red soil as a natural adsorbent for phosphate removal from wastewater
(2015) Rout P.R.; Bhunia P.; Dash R.R.
The present study was conducted to investigate the efficacy of red soil (RS), as a natural adsorbent, for phosphate removal from wastewater. The chemical composition of the adsorbent was determined by proton-induced X-ray emission and proton-induced ?-ray emission methods. Apart from evaluating the influence of major experimental parameters, the equilibrium data were analyzed by different isotherm models and kinetic models. Experimentally obtained values, such as separation factor (RL), 0.0297, Freundlich exponent (n), 2.994, and Gibb�s free energy change (?G�), ?1.279 kJ mol?1, suggest that the phosphate adsorption by RS was a favorable and spontaneous process. The presence of coexisting anions showed no competing effects on phosphate removal efficiency. For synthetic initial phosphate concentration of 20 mg L?1 and contact time of 90 min, phosphate removal efficiency was 96.47% in batch mode and 19 h of breakthrough time in column mode. Whereas with real domestic wastewater having 5.62 mg L?1 of initial phosphate concentration, removal efficiency was as high as 99.8% in batch mode and 70 h breakthrough time in column mode. The results of this study suggested that RS can be used as a low-cost and highly efficient adsorbent for phosphate removal from wastewater. � 2014, � 2014 Balaban Desalination Publications. All rights reserved.
A mechanistic review on vermifiltration of wastewater: Design, operation and performance
(2017) Singh R.; Bhunia P.; Dash R.R.
With global population explosion, the available water resources are slowly being polluted due to the excessive human interference. To encounter this, it is the need of this hour to find out sustainable pollution remediating technologies to meet the stringent discharge standards for domestic as well as industrial wastewaters. In addition, those techniques should have the capabilities for effective implementation even in developing countries. Based on the available literatures, one such technique, named vermifilter, has been identified which takes care of almost all the sustainable and economical criteria for its effective implementation even in developing countries. The aim of this meta-analysis is to provide a comprehensive review on assessment mechanisms involved, factors affecting the process and performance of vermifiltration under different scenarios. The present review envisages the current state of the knowledge regarding physical, chemical and biological aspects related to the treatment mechanisms and effective functioning of earthworms. This review has also proposed several suggestive plans on its application at any proposed site. � 2017 Elsevier Ltd
Modeling isotherms, kinetics and understanding the mechanism of phosphate adsorption onto a solid waste: Ground burnt patties
(2014) Rout P.R.; Bhunia P.; Dash R.R.
The objective of the present study was to investigate the adsorption behavior of grounded burnt patties (GBP), a solid waste generated from cooking fuel used in earthen stoves, as an adsorbent for phosphate removal from aqueous solution. The characterization of adsorbent was done by proton induced X- ray emission (PIXE), and proton induced ?-ray emission (PIGE) methods and the adsorption mechanisms by Fourier transferred infra-red spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. The effects of adsorbent dose, contact time, initial solution concentration, agitation, etc. on the uptake of phosphate by the adsorbent in batch mode were examined. The equilibrium data were fitted to different types of adsorption isotherms and kinetic models. Freundlich isotherm model and pseudo-second-order kinetic model illustrated best fit to the data. The favorability and spontaneity of the adsorption process are established by the values of experimentally calculated parameters such as separation factor (RL), 0.03, Freundlich exponent (n), 3.57 and Gibb's free energy change (?G�), -1.32 kJ/mol. The presence of coexisting anions showed no competing effects on phosphate removal efficiency. Breakthrough curves obtained from column study revealed that the lower flow rate and higher bed heights result in longer column saturation time. The results of this study suggested that GBP can be used as a low cost, highly efficient adsorbent for phosphate removal from aqueous solution. � 2014 Elsevier Ltd.