BITS Faculty Publications
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Item Remediation of Waste Engine Oil Contaminated Soil using Rhamnolipid based Detergent Formulation(Elsevier, 2023) Jain, Amit; Gupta, Suresh; Chattopadhyay, PradiptaThe utilization of waste substrates for rhamnolipid synthesis is a worthy alternative to conventional substrates to reduce the production cost of rhamnolipids. Rhamnolipid produced by Pseudomonas aeruginosa gi |KP 163922| using waste engine oil as substrate was investigated in batch and semi-batch studies for soil bioremediation. Green liquid detergent formulations were prepared by using environment-friendly builder (sodium citrate) and filler (isopropyl alcohol). Rhamnolipid, a biosurfactant was utilized in place of chemical surfactant to prepare the liquid detergent formulation. The formulations at different rhamnolipid concentrations i.e., below critical micelle concentration (CMC), at CMC, and above CMC, were tested for soil remediation efficiency. Each detergent formulation was characterized based on emulsification index (EI24%), surface tension reduction, foam ability, and foam stability. The in-house rhamnolipid based formulations above CMC, recovered oil up to 82.02 ± 0.938 % from contaminated soil with maximum surface tension reduction and foam volume as 26.5 ± 0.412 mN/m and 51.10 ± 1.37 mL respectively. The proposed remediation strategy demonstrated that the recovery of oil is possible at room temperature conditions. The performance properties including detergency and foaming of rhamnolipid based liquid detergent formulations were also compared with commercial rhamnolipid and other detergents.Item Assessment of bimetallic Zn/Fe0 nanoparticles stabilized Tween-80 and rhamnolipid foams for the remediation of diesel contaminated clay soil(Elsevier, 2023-01) Roy, Banasri; Chattopadhyay, PradiptaDiesel contamination of soil due to oil spills, disposal of refinery waste, oil exploration constitutes a major environmental problem. This paper reports the remediation of diesel contaminated clay soil using Zn/Fe0 bimetallic nanoparticle stabilized Rhamnolipid (RMLP) and Tween-80 (TW-80) surfactant foams. Fe0, and Zn (x wt%)/Fe0 (x = 0.2, 2.0, and 10.0) bimetallic nanoparticles are synthesized by using sodium borohydride reduction method. The average particle size (from FESEM) is calculated to be 62, 57, 42 and 35 nm for the Fe0, Zn (0.2)/Fe0, Zn (2)/Fe0 and Zn (10)/Fe0 nanopowders, respectively. The highest foamability and foam stability of 109.6 and 108.5 mL, respectively are observed for the RMLP (12 mg/l) surfactant foam stabilized with 6 mg/l Zn (10)/Fe0 nanoparticles. The surface tension values reduce to the lowest value of 28.1 and 31.4 mN/m with the addition of 6 mg/l of Zn (10)/Fe0 powder in RMLP and TW-80 solutions of 12 mg/l, respectively. The maximum diesel removal efficiency of 83.8 and 59%, is achieved by RMLP (12 mg/l) foam stabilized by Zn (10)/Fe0 nanoparticles (6 mg/l) for the clay soil contaminated with 100 and 500 μl/g of diesel, respectively. The physicochemical properties of the nanoparticles are studied to explain the foam properties and the remediation behavior. These findings regarding the nanoparticle stabilized foams can offer a cost-effective environment friendly commercial solution for soil remediation in the future.Item Foam Over’ Temperatures Using Glass Coker Experimentation: A Case Study(IUP, 2011-09) Chattopadhyay, PradiptaIn petroleum refineries, excessive foaming in process equipments leads to inefficiency and higher maintenance cost. A very relevant aspect of current petroleum refinery operations is the heating up of vacuum resid in a coke drum and the subsequent generation of unwanted foam. This research paper describes the foam produced by heating vacuum resid in a glass coker experimental set up in terms of foam over temperature. The vacuum resids for analysis were obtained from major US oil companies like Chevron, Shell, Petrobras, etc. Run data are provided that illustrate the variation of foam over temperature for different vacuum resids and at what time the foam over phenomenon started during the glass coker run. Also the production of white vapors (an intermediate stage for foam generation), in terms of the first incidence of white vapor temperature have been reported. The experimental results clearly lead to the fact that foaming during a glass coker run is dependent on the resid (feedstock) properties and run operating conditions.Item Experimental Determination of Foaming Characteristics of Aqueous Iso-Propanol Solution by Addition of Surfactants(WRA, 2011) Chattopadhyay, PradiptaFoams are colloidal systems in which a gas phase is dispersed throughout a continuous liquid phase. The development and stability of aqueous foams have long been of great practical interest because of their widespread occurrence in everyday life. Which parameters influence and govern the aqueous foam development and lead to stable foam formation are critical for soap and detergent manufacturing industries. In the series of experiments conducted, aqueous isopropanol was used as the chief solution where the foaming would be observed. The detergents Surf Excel Blue and Tide were used as surfactants for the foam production. As a result of the tests performed, Foaminess or foam producing capability and foam persistence time were obtained. The results show a distinct correlation between foaming characteristics and concentrations of aqueous isopropanol and surfactants used.Item Optimum Ethanol-Hexanol Foams for Formulation of Detergents(IJCS, 2015) Chattopadhyay, PradiptaThe accurate and speedy characterization of aqueous foams generated by the use of surfactants are critical for the formulation of soaps and detergents. This paper describes details of experimental studies directed towards measurement of foaming properties of mixture of ethanol, hexanol and sodium lauryl sulfate (SLS). The experimental results are of great relevance with respect to the formulation of detergents, which can be generated by use of alcohol-surfactant mixtures. The foams were generated by the injection of air at a constant flow rate of 5 mL/sec into aqueous mixtures of ethanol, hexanol with sodium lauryl sulfate. The foams were then characterized using a Dynamic Foam Analyzer (Kruss GmbH, Germany). The foamability, stability parameters like foam capacity, RMI 30, were determined and their variation with changes in ethanol, hexanol and SLS amounts added to solution were noted. Model equations for foam capacity and RMI 30 were developed by using the Central Composite Experimental Design (CCD) approach of Response Surface Methodology (RSM), statistically analyzed and validated. The responses obtained in the study were foam capacity (FC) and RMI 30 in mL. Numerical optimization for two different strategies for the responses, were subsequently performed by using Design-Expert Software version 9.0.4.1. The optimum responses FC and RMI 30 were found to be in reasonable agreement with the experimental results.Item Optimum Dodecanol-detergent foam performance for formulation of eco-friendly surfactants(WRA, 2016-03) Chattopadhyay, PradiptaOptimum foam performance is of tremendous importance from the standpoint of formulation of biodegradable, environmental friendly surfactants. To gain deeper understanding on foams required for judging such surfactants, aqueous foams generated by the use of mixtures of dodecanol, n-butanol and popular detergent Surf Excel were first characterized using a Dynamic Foam Analyzer DFA 100 (Kruss GmbH, Germany) for parameters like foam capacity and RMI 30. Mathematical models for foam capacity and RMI 30 were developed by using the Central Composite Experimental Design (CCD) approach of Response Surface Methodology and then statistically analyzed and validated. The responses obtained in the study were foam capacity (FC) and RMI 30 in mL. Numerical optimization for the responses, using the model equations developed, was performed by using Design- Expert Software version 9.0.4.1. The optimum values of responses FC and RMI 30 were found to be in reasonable agreement with the experimental resultsItem Optimum Isopropanol foams for soil remediation applications(WRA, 2016) Chattopadhyay, PradiptaItem An in-Depth Analysis of Ethanol Based Aqueous Foams for Environmental Applications(IJCS, 2016) Chattopadhyay, PradiptaThe foamability parameters of surfactant generated aqueous ethanol based foams are critical for remediation of petroleum hydrocarbon contaminated soil. To gain more insight into foams that will be suitable for this application, different aqueous foams were generated by the use of ethanol, surfactant Sodium Lauryl Sulfate (SLS), constant injection of air and then tested for foaming capability, using a Dynamic Foam Analyzer (Kruss GmbH, Germany). The results showed that 30 volume % ethanol solution with 10 mg of SLS added was the best in terms of foamability and thus well suited for soil remediation.Item Remediation of Diesel Contaminated Soil by Tween-20 Foam Stabilized by Silica Nanoparticles(IJCEA, 2017-06) Chattopadhyay, PradiptaDiesel oil spills into soil from petroleum storage areas, pipelines are a major environmental hazard. There is thus an increasing demand for new, efficient agents for remediation of diesel contaminated soil. The aim of this study therefore was to analyze the efficiency of application of nanoparticle stabilized nonionic surfactant foams for remediation of diesel contaminated soil. Stable foams were produced from dispersions of hydrophilic, hydrophobic silica nanoparticles with nonionic surfactant Tween-20. The foam generated was then transferred to a column containing the contaminated soil. The maximum diesel oil removal efficiency obtained by applying Tween-20 foam stabilized with 0.5 wt% hydrophobic silica nanoparticle was 78%- much higher than that obtained for Tween-20 foam stabilized with 0.5 wt% hydrophilic silica nanoparticles. The Tween-20 surfactant solution alone showed only 42% maximum oil removal efficiency.Item Characterization and Application of Surfactant Foams Produced from Ethanol-Sodium Lauryl Sulfate-Silica Nanoparticle Mixture for Soil Remediation(Wiley, 2017) Chattopadhyay, PradiptaSoils contaminated with diesel oil spilling from industrial areas, pipelines constitute a major environmental problem. This subsequently leads to the contamination of groundwater as well. Hence recently there is an increasing trend of usage of better techniques and agents that can perform diesel oil contaminated soil remediation with greater efficiency. The aim of this study is to report the potential, efficiency of using silica nanoparticle stabilized anionic surfactant foams for diesel contaminated soil remediation and also the different characteristics of the foam produced. Also comparison in terms of soil remediation efficiency using surfactant dispersions only were performed. The foams were produced from dispersions comprising of ethanol, anionic surfactant sodium lauryl sulfate (SLS) and silica nanoparticles, both hydrophobic and hydrophilic. The foamability and stability of the different foams were determined using the Dynamic Foam Analyzer DFA 100 (Kruss GmbH, Germany). The surfactant foams generated were then applied to the contaminated soil using a fabricated column. The results showed the gradual stabilization of the SLS foams by the use of the silica nanoparticles. The maximum diesel oil removal efficiency obtained by applying foam stabilized with 0.3 wt% hydrophobic silica nanoparticle, 10 vol% ethanol, 0.1 vol% SLS was 94.5%. The 0.3 wt% hydrophobic silica nanoparticle, 10 vol% ethanol, 0.1 vol% SLS surfactant solution showed only 61.5% maximum oil removal efficiency.