separation of ten sedative- hypnotic drugs was performed by rp-hplc using mixed micellar mobile phase. effect of temperature, type and amount of organic modifier in mobile phase on efficiency (n) and asymmetry factor (b/a) showed that, the appropriate conditions for a good separation were 35°c and 7% (v/v) butanol in mobile phase.  variations of selectivity factor versus butanol concentration, ...

a second virial coefficient correlation suitable for two different temperatures ranges, (t*)-2£180 and (t*)-2>180, where t* is rt/dhvap is presented. the equation of state can be calculated for different, complicated non-polar, and slightly polar liquid mixtures at any temperature over the range from ttp to tc and up to high pressures. the latent heat of vaporization and density at the triple p...

in this study, a three–layer artificial neural network (ann) model was developed to predict the pressure gradient in horizontal liquid–liquid separated flow. a total of 455 data points were collected from 13 data sources to develop the ann model. superficial velocities, viscosity ratio and density ratio of oil to water, and roughness and inner diameter of pipe were used as input parameters of t...

this research includes both experimental and cfd investigation in the hydrodynamic behavior of a new type of column tray introduced as “concap” tray. the proposed column tray is used in contactor columns especially in stripping columns. the hydrodynamics of this concap tray is investigated in a 1.2m in diameter column. using air-water system, the experiments were performed for different liquid ...

In this study, liquid-liquid extraction process in a Kuhni extraction column was modeled and simulated. A non-equilibrium dynamic model was developed for modeling liquid-liquid extraction processes based on a rate-based model. The model equations are inclusive of partial and ordinary differential equations which were discretized in column height direction. The population balance model was used ...

platinum extraction from different secondary sources has been experimentally tested by many researchers. in this article, dissolution of platinum in aqua-regia solution from two types of spent catalysts (reforming and nitric acid production) was kinetically studied. a variety of kinetic models for heterogeneous solid-liquid reactions, including homogeneous diffusion model, shrinking core model,...

The kinetics of the potassium thiocyanate transport mediated by dicyclohexyl-18-crown-6 (L) through a bulk liquid membrane is studied experimentally and theoretically. The proposed model is based on the assumption of a pure diffusion of the complex salt [K·L]+SCN¯ through the liquid membrane stagnant films at the interfaces. It illustrates the ...

the aim of this paper is to study the local nusselt number of the symmetrical liquid-liquid jets emitting from a nozzle. equations obtained from theoretical works are arranged in the form of a computerized model. the validity of this model was tested by the data from an experimental paper [1]. after few adjustments the model predicted the experimental data with a reasonable accuracy. making sur...