â a model is developed for separation of multicomponent gas mixtures in a countercurrent hollow fiber membrane module. while the model’s solution in countercurrent module usually involves in a time consuming iterative procedure, a proper initial guess is proposed for beginning the calculation and a simple procedure is introduced for correcting the guesses, hereby the cpu time is decreased ess...

because most contaminants in water create strong interactions with hydrophobic surfaces, there are usually problems such as flux decline and pore blocking in polyethylene (pe) membranes due to irreversible adsorption of foulants on their intrinsic hydrophobic surface. therefore, in this work, attempts were made to improve the properties of pe membranes in terms of water flux and membrane foulin...

In nanofiltration (NF), solution and membrane chemistry determine the charge density. multi-component electrolytes solutions, it is important to consider interaction between ions NF membranes. For instance, in presence of divalent ions, reversal can take place due counterions with charged functional groups membrane. This paper presents a model based on state-of-the-art mean-field theory that in...

A PVC membrane electrode based on 1-[({[(butylsulfunyl)carbothioyl]disulfanyl} carbothioyl)sulfanyl]butane as a suitable ion carrier for determination of lanthanum(III) ion was prepared. This electrode revealedsuch a good selectivity toward La3+ ion over a wide variety of other metal ions. Some experimental parametersuch as membrane composition, nature, and amount of plasticizer, the amount of ...

This study investigated the effect of Cloisite15A (C15A) organoclay in the substrate layer on the performance of reverse osmosis (RO) membranes. The substrate of the RO membranes was modified using different loading of C15A (ranging from 0.3 - 0.7 wt%) within polysulfone (PSf) substrate and the polyamide (PA) selective layer was formed on the top. Effect of the modified substrate layer on the w...

1. It is shown that when part of the gelatin in a solution of gelatin chloride is replaced by particles of powdered gelatin (without change of pH) the membrane potential of the solution is influenced comparatively little. 2. A measurement of the hydrogen ion concentration of the gelatin chloride solution and the outside aqueous solution with which the gelatin solution is in osmotic equilibrium,...

the current study presents synthesis and characterization of high impact polystyrene - tio2 nanoparticles mixed matrix membranes for separation of carbon dioxide from nitrogen. the solution-casting method was used for preparation of membranes. the nano mixed matrix membranes were characterized using scanning electron microscopy to ensure the suitable dispersion of nano particles in high impact ...

An optimization-based procedure for estimating unknown parameters in solution-diffusion models of membrane pervaporation is presented. Permeation of two components through a polymer membrane is described by distinct solution and diffusion models. The solution model is based on a modified form of Flory-Huggins theory that accounts for interactions between the two penetrants. The diffusion model ...