Informatics Publishing Limited

Sahil Garg ¹, A. M. Shariff ¹, M. S. Shaikh ¹, Bhajan Lal ¹, Asma Aftab ¹, Nor Faiqa ¹

Affiliations
1 Research Centre for CO2 Capture (RCCO2C), Department of Chemical Engineering, Universiti Teknologi PETRONAS, Seri Iskander, Perak Darul Ridzuan 32610, MY

Abstract

Objectives: To investigate experimental data of surface tension of aqueous sodium salt of L-phenylalanine (Na-Phe) at temperatures ranging from 298.15 to 343.15 K and concentration ranging from 0.05 to 0.40 (w). Methodology: This work was carried out through an optical contact angle tensiometer (OCA 15 EC). It is a video based instrument which employs a pendant drop method for contact angle measurement. Findings: It was observed that surface tension values rise as aqueous Na-Phe concentration increases and decrease with the increase in system’s temperature. Experimental surface tension data were used to calculate the dervied surface thermodynamic properties such as surface enthalpy and entropy. Surface enthalpy was found to increase with concentration and tend to decrease with the rise in temperature. While, estimated surface entropy values were found to decrease with the increase in Na-Phe concentration. Temperature and concentration dependent empirical correlation was utilized to predict the surface tension data. A good agreement was found between the experimental and correlated data. Applications/Improvements: The findings reported in this study could be helpful significantly for the selection of appropriate solvent, and in the calculations for the efficient design of absorption column.

Keywords

L-Phenylalanine, Surface Tension, Sodium Salt, Surface Enthalphy, Surface Entropy.

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Muhammad Saad Khan ¹, Bhajan Lal ¹, Cornelius B. Bavoh ¹, Lau Kok Keong ¹, Azmi Bustam ¹, Nurhayati Bt Mellon ¹

Affiliations
1 Chemical Engineering Department, Universiti Teknologi PETRONAS, 32610 Bandar Seri Iskandar, Perak Darul Ridzuan, MY

Abstract

Objectives: In natural gas transmission pipelines hydrate formation is major flow assurance challenge. This communuication presents as brief review focuses on the potentially applicable area of Ammonium based compounds (ACs) as gas hydrate inhibition. Methods/Statistical Analysis: For avoiding gas hydrate formation, oil and gas industry spent millions of dollar annually without any permanent solution. In most of the cases insertion of chemicals (inhibitor) established as the utmost supreme route for gas hydrate mitigation. Quantary ammonium salts had widely been applied as commercial hydrate inhibitors. Ammonium based Ionic Liquids (AILs) also recently applies as work as potential gas hydrate inhibitor for hydrate mitigation. Findings: The systematic review on ACs proves that higher concentration of ACs provides more effective thermodynamic inhibition. The alkyl chain length of ACs playsan important part, as the chain length increases it decrease their effectiveness as inhibitors. Usually, imidazolium based ILs employed as gas hydrate inhibitors contains fluorinated anions which categorized as toxic compound. ACs holds the strong tendency to act as the dual function chemical inhibitor for possible replacement of widely used imidazolium based ILs due to their cheaper source, easy synthesis along with fairly better environmentally friendly nature. Application/Improvements: This study will highlight the recent advancements achieved in the field of ACs, highlighting the vigorous prospects of ACs as potential gas hydrate inhibitors and provide the avenue to accomplish flow assurance problems caused due to gas hydrates

Keywords

Ammonium based Compounds (ACs), AIL, Gas Hydrate, Inhibitors, KHI, THI.

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Anwar Ali ¹, Anil Kumar Nain ¹, Bhajan Lal ¹

Affiliations
1 Department of Chemistry, Jamia Millia Islamia (Central University), Jamia Nagar, New Delhi-100025, IN

Abstract

The ultrasonic speeds, U and densities, ρ of pure benzene, n-butanol, iso-butanol, sec-butanol and tert-butanol and their binary mixtures with benzene as a common component were measured at 30°C over the whole composition range. The dependence of ultrasonic speed on composition of the mixture was checked by using an empirical relation. From the experimental data, the values ofisentropic compressibility, ks, intermolecular free length, L_f, relative association, R_A, acoustic impedance, Z, molar sound speed, R_m, deviations in isentropic compressibility, Δk_s, excess intermolecular free length, L^E_f, deviations in ultrasonic speed, ΔU, excess acoustic impedance, Z^E, apparent molar compressibilities, K_∅,1 and K_∅,2 and partial molar compressibilities, ̅K°_∅,1 and ̅K°_∅,2 of benzene in alcohols and alcohols in benzene, respectively, at infinite dilution were calculated. The variation of these parameters with composition indicates the presence of weak interactions between the component molecules and this interaction decrease in the order: n-butanol>iso-butaitol>sec-butanol>tert-butanol. Further, the ultrasonic speeds in these mixtures were theoretically calculated with the help of several theories and empirical relations by using data on pure components. The relative merits of these theories and relations for the present systems have been discussed.

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