the molecular sieves are selective adsorbents. they can adsorb some kind of molecules that are different in size or shape from the others. in separation of n-paraffins from iso-paraffins and aromatics, sa molecular sieve is the suitable adsorbent, and can adsorb n-paraffins to separate them from other hydrocarbons. in this paper equilibrium isotherms of n-cs, n-c6 and n-c7 from an inert solvent...

poly urea-formaldehyde was synthesized simply and rapidly from urea and formaldehyde by condensation polymerization and studied for the sorption of trace acid blue from aqueous solution. the optimum ph value for sorption of the acid blue was 4. experimental results showed that the sorption capacity of poly urea-formaldehyde for acid blue was determined. the synthetic polymer can be reused for 5...

The present work was carried out to evaluate the removal of p-nitrophenol by adsorption onto olive cake based activated carbon having a BET surface area of 672 m²/g. The batch adsorption experimental results indicated that the equilibrium time for nitrophenol adsorption by olive cake-based activated carbon was 120min. The adsorption data was modeled by equilibrium and kinetic models. The pseudo...

The occurrence of contaminants in wastewaters, and their behavior during wastewater treatment and production of drinking water are key issues to re-use water resources. The present research aims to remove caffeine from aqueous solutions via adsorption technique, using Multi-Wall Carbon Nanotubes (MWCNTs) as an adsorbent under different experimental conditions. The processing variables such as p...

In this study adsorption of 1-chloro-4-nitrobenzene on single walled carbon nanotubes has been investigated.  The effect of contact time, pH, initial concentration of 1-chloro-4-nitrobenzene, adsorbent dosage and temperature on its adsorption has been carried out in order to find optimum adsorption conditions. Adsorption isotherms and related constants were also determined. Results showed that ...

The adsorption and desorption of paraquat (1, l'-dimethyl-4,4'-dipyridylium dichloride) in two tropical soils was determined under laboratory conditions. The two soils were taken from rice fields located in the North West of Perak state. The adsorption equilibrium time was 2 hours for both soil types. This adsorption equilibrium time was used to determine the effect of concentration on adsorpti...

Adsorption on activated carbon is one of the most reliable and efficient technologies for the remediation of water polluted by heavy metals. In groundwater remediation, it actually found practical application in both pump-and-treat systems and permeable adsorbing barriers. One of the most significant limits to the practical adsorption of heavy metals in water streams is the absence of experimen...

Ala~ntct--Tbe performance characteristics of two activated carbons and eight synthetic adsorbents are compared. The comparison addresses both the equilibrium capacities and mass transport properties of the adsorbents. A new empirical adsorption isotherm is employed for description of adsorption equilibrium data. A' predictive mathematical model is used for forecasting adsorption bed performance...

Adsorption equilibria were analyzed on the basis of general equilibrium constant expression for the development of fundamental adsorption equations (Freundlich, Langmuir, and BET) in connection with the establishment of a general approach towards physical interpretations of adsorption parameters. Theoretically it was proved that Freundlich plot analysis cannot be used to find useful parameters ...

Fine particles Silicoaluminophosphate-34 were synthesized by hydrothermal sol-gel method. The effect of crystallization time, as one of the important synthesis factors on particle size and crystallinity, kinetic and equilibrium adsorption, and selectivity of CO2 / CH4 has been studied in this work. The adsorption isotherms are obtained at mod...