NOPR Collection:

Effect of the membrane operating parameters on the separation of oxygen and hydrogen disulphide

2016-07-20T05:35:06Z

Title: Effect of the membrane operating parameters on the separation of oxygen and hydrogen disulphide Authors: Asadi, S; Mosavian, M T Hamed; Ahmadpour, A Abstract: The processes of separating oxygen in air and H₂S in the acid gas feed using a membrane process are based on the relative permeability of components in the feed and are done due to the pressure difference between membrane sides. The mathematical modeling and simulations of the membrane separation processes is solved using EES software without the need for programming outside of the simulator. Passing flow through the membrane is considered counter current and the simulation is done according to the characteristics of hollow fibre membranes. In this study, using this simulator, the percentage of separating components (oxygen and H₂S) of the air and sour gas in the two output flow of the membrane and effect of different parameters on the separation percentage of these components is reviewed. With increasing the feed flow (air and acid gas feed), oxygen and H₂S concentration output of the membrane is decreased. However, concentrations of these components have direct correlation with the selectivity and membrane surface area. In addition, the effect of the feed pressure on the oxygen and H₂S percentage output of the membrane is a function of the permeate pressure. Page(s): 77-80

Spectrophotometric determination of Pt(IV) with N-decylpyridine-4-amine from succinate media

2016-07-20T05:31:40Z

Title: Spectrophotometric determination of Pt(IV) with N-decylpyridine-4-amine from succinate media Authors: Bagal, M R; Dhokte, A O; Vaidya, S R; Lande, M K; Arbad, B R Abstract: N-decylpyridine-4-amine in xylene is used for the extractive separation of platinum(IV) from succinate media. Platinum(IV) has been extracted quantitatively with 10 mL of 1 × 10^-4M reagent in xylene from 0.025 M succinic acid . It is stripped from organic phase with water and estimated spectrophotometrically with stannous chloride. The effect of metal ions, acid, reagent concentrations and various foreign ions has been investigated. The method affords quantitative binary separation of platinum from base metals, and is applicable to the analysis of synthetic mixtures and alloys. The method is fast, accurate and precise. The molar absorptivity and Sandell’s sensitivity of Platinum(IV)-N-decylpyridine-4-amine complex is found to be (4.9×10⁵L mol^-1 cm^-1) and (0.0078 µg cm^-2), respectively which indicates the applicability of the method. Page(s): 71-76

Determination of chloride and sulfate in bio-ethanol by ion chromatography

2016-07-20T05:29:04Z

Title: Determination of chloride and sulfate in bio-ethanol by ion chromatography Authors: Tomić, Tatjana; Milčić, Martina; Nasipak, Nada Uzorinac; Babić, Sandra Abstract: Bio-ethanol is produced from biomass or biodegradable waste and is used as a blending component in commercial gasoline fuel. Bio-ethanol can be contaminated with chloride and sulfate ions which can cause various unwanted side effects. European norm, EN 15376 defines the maximum permitted level of ions present and by that maximum chloride and sulfate content should not exceed 6.0 mg·kg^-1and 4.0 mg·kg^-1, respectively. The optimization and validation of ion chromatography method for the quantitative determination of chloride and sulfate ions in bio-ethanol by direct injection ion chromatography using anion-exchange stationary phase, carbonate/hydrogen carbonate mobile phase and conductivity detection has been described. The method is optimized regarding mobile phase composition and flow rate as well as the length of the chromatographic column. Validation of the method has been performed in order to confirm its applicability. The developed method is applied for the determination of chloride and sulfate ions in real bio-ethanol samples used for inter-laboratory comparative testing. The obtained results are compared with the official tests results and z-score has been determined. For chloride determination higher z-scores is obtained (from 1.4 to >3) than for the determination of sulfate (from -0.9 to 0.1). Page(s): 65-70

Characteristics of gas pressure drop of a countercurrent-flow rotating packed bed

2016-07-20T06:00:37Z

Title: Characteristics of gas pressure drop of a countercurrent-flow rotating packed bed Authors: Qi, G S; Wang, H; Liu, Y Z; Zhu, Z W; Tian, J X; Fu, J Abstract: The gas pressure drop of rotating packed bed (RPB) is an important indicator for measuring its performance. This work examines pressure drop using air-water system in which the RPB can be operated from 0 to 800 r/min and the gas flow rate can be ranged from 200 to 1100 m³/h and the liquid flow rate can be varied from 0 to 9 m³/h. Results show that the pressure drop of dry bed increases with increase in gas flow rate and rotor speed while that of wet bed is the same without flooding. The phenomenon of flooding occurs in range of lower rotor rate when the gas flow rate is large enough. The pressure drop of dry bed is lower than that of wet bed when the rotor rate is low, vice versa counter. This work lay the foundation for the design and application of RPB industrialized on both the theoretical and experimental side. Page(s): 59-64