Sayan Roychowdhury

Bio: Sayan Roychowdhury is an academic researcher from University of Calcutta. The author has contributed to research in topics: Pervaporation & Phenanthrene. The author has an hindex of 3, co-authored 5 publications receiving 18 citations.

Separation of phenanthrene/N‐tetradecane mixtures (model diesel) via pervaporation using an aromatic polyimide membrane

Abstract: The present investigation focuses on the separation of phenanthrene (a polyaromatic hydrocarbon) from n-tetradecane (model diesel composition) via pervaporation using a fabricated aromatic polyimide membrane. The experiments demonstrate preferential permeation of the polyaromatic for all films within the studied experimental range. The influence of operating temperature, membrane pretreatment time, membrane composition, and membrane thickness on the pervaporative performance were investigated. Statistical software Design Expert 7.1.4 was used to derive the regression equation describing the effect of the above mentioned factors on the pervaporation separation index. These factors are optimized using response surface methodology. The highest value of pervaporation separation index obtained is 1.5277 kg m−2 h−1 and the corresponding optimized condition is: operating temperature 493 K, pretreatment time 16.55 h with a membrane composition of 2.76 wt% of phenanthrene in polyamic acid and thickness 53.22 µm. POLYM. ENG. SCI., 57:392–402, 2017. © 2016 Society of Plastics Engineers

Fabrication of Aromatic Polyimide Membrane to Study the Pervaporative Separation of Phenanthrene/n-tetradecane Mixtures (Model Diesel) and Process Optimization Using Response Surface Methodology

Abstract: To meet stringent fuel specifications, separation of aromatics from aliphatics is an everyday challenge for a refiner. In the present investigation, an aromatic polyimide membrane is fabricated and explored for the separation of a polyaromatic hydrocarbon (phenanthrene) from a model diesel composition (n-tetradecane) via pervaporation. The pervaporative membrane is prepared by casting a solution of polyamic acid, N,N-dimethylacetamide (DMAc), and phenanthrene using a simple and low-cost procedure. Scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FTIR), and swelling in feed solution of the synthesized membrane have been conducted for its characterization. The membrane allows preferential permeation of phenanthrene. The influence of different physico-chemical parameters, on permeation flux and enrichment factor for n-tetradecane/phenanthrene mixtures, has been studied. Statistical software Design Expert 7.1.4 is used to derive the regression equation, which describes the effect o...

Separation of benzo[a]pyrene and n-tetradecane mixtures using pervaporation technique and optimization

Abstract: Benzo[a]pyrene is a carcinogen often present in diesel. For pervaporative removal of benzo[a]pyrene from n-tetradecane, representing a model diesel composition, both conventional as well as statistically designed experimental methods have been carried out. The effect of membrane composition, thickness, the effect of membrane pretreatment time and operating temperature on pervaporative separation have been investigated by response surface methodology, RSM for efficient permeation of target compound. The suitable membrane has been further used to study the effect of different physico-chemical parameters on permeation conventionally. RSM has also been applied to optimize the operational conditions of pervaporation process to maximize the response, i.e., the pervaporation separation index. With the design of experiments, the quadratic response surface models have been developed to link the response with input variables via mathematical relationships. The maximum value of Pervaporation Separation Index obtained is 1.9654 kg m−2 h−1. The optimized process condition’s run time is 10.79 h, the feed PAH concentration is 166.34 ppm with a permeate side pressure of 0.73 mmHg and an operating temperature of 451.25 K.

The Design and Analysis of Experiments

Abstract: THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

Desulfurization performance of polydimethylsiloxane membranes by pervaporation: Effect of crosslinking agents

Abstract: Polydimethylsiloxane (PDMS), as one of the typical membrane, has been widely applied in gasoline desulfurization via pervaporation. In this work, the PDMS/PVDF composite membranes were prepared by curing PDMS with three different crosslinking agents. They were 3-Aminopropyltrimethoxylsilane (APTMS), 3-Glycidyloxypropyltrimethoxylsilane (GPTMS), and 3-Mercaptopropyltrimethoxylsilane (MPTMS), respectively. These PDMS/PVDF composite membranes were characterized by Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM), and then evaluated by static tensile test, swelling degree test and surface detach experiment. The results showed that A-PDMS membrane had highest crosslinking density, best anti-swelling ability and excellent combination between the separation layer and support layer. Moreover, the effect of operation temperature and the feed sulfur content on separation performance were investigated systematically. Experimental results indicated that PDMS membrane crosslinked with APTMS presented the highest enrichment factor with 3.46°C at 45°C, and PDMS membrane crosslinked with MPTMS presented the highest permeation flux with 21.19 kg/(m2·h) at 45°C. Finally, long-term stability test showed that these PDMS membranes all have desirable stability. POLYM. ENG. SCI., 57:1127–1135, 2017. © 2017 Society of Plastics Engineers

Optimization of electro-kinetic process for remediation of soil contaminated with phenanthrene using response surface methodology

Abstract: The objective of this work was to investigate the modification of soil contaminated with phenanthrene (PHE) by electro-kinetic remediation (EKR) process using response surface methodology (RSM). The soil sample was obtained from the subgrades (0–30 cm) of an area close to Shahroud City, Northeast of Iran. The effect of variables such as initial pH, voltage, electrolyte concentration, and reaction time on PHE removal was studied. Based on the results obtained from the central composite design (CCD) experiment, the highest and lowest amount of PHE removal was 97 and 20%, respectively. In this study, the variables A, B, C, AB, AC, and C2 with a p value < 0.05 were significant model terms and the parameter of the lack of fit was not significant (p value = 0.0745). Findings indicated that the “predicted R-squared” of 0.9670 was in reasonable agreement with the “adj R-squared” of 0.9857 and the plot of residual followed a normal distribution and approximately linear. Also, the kinetic rates of the removal PHE by the EKR process best fitted with a first-order kinetic model (R2: 0.926). Results of the investigation of the effective variables showed that in values of pH 3, time of 168 h, voltage of 3 V, and electrolyte concentration of 4 mg/L, the removal efficiency of PHE reached 96.6%.