isotherm equation is one of the important scientific bases for adsorbent selection. there are different isotherms that do not account for an adsorbate, different chemisorption geometries on the nanoporous surface. it is interesting to introduce a general isotherm, which considers different chemisorption geometries of an adsorbate on nanoporous surfaces. in this study, an isotherm for non-dissoci...

background and objectives: analytical methods for volatile organic compounds (vocs) in different samples need extraction of compounds, by applying hazardous solvents. solid phase micro-extraction (spme) is a solvent-free equilibrium extraction method, in which proper calibration can allow quantitative determinations of vocs at a very good sensitivity without the use of any organic solvent. vocs...

background: determination of organic pollutants usually requires extraction of the pollutants from samples, using hazard­ous solvent. solid phase micro-extraction (spme) is a solvent-free equilibrium extraction method, in which, proper calibra­tion can allow quantitative measurements of organic pollutants at a very good sensitivity without the use of any organic sol­vent. because individual voc...

acetonitrile used as a solvent in manufactures and affects to central nervous system from inhalation exposure. the aim of this study was to develop a micro-solid phase extraction method for  the determination of acetonitrile in the air matrix. the sampling was performed with a small diameter fused silica fiber coated with a thin film of stationary phase and was subsequently desorbed and analyze...

heat transfer phenomena in batch fluidized bed dryer have been studied and analyzed using three phase model including solid phase, interstitial gas phase and bubble phase based on rizzi model. new correlations of heat transfer coefficient to surrounding and convection heat transfer coefficient between solid and interstitial gas are being proposed. in addition, some modifications have been done ...

This paper presents a numerical investigation for laminar forced convection flow of a radiating gas in a rectangular duct with a solid element that makes a backward facing step. The fluid is treated as a gray, absorbing, emitting and scattering medium. The governing differential equations consisting the continuity, momentum and energy are solved numerically by the computational fluid dynamics t...

effective methodologies for efficient preparation of semicarbazones from aldehydes or ketones via milling and the subsequent regeneration of the parent carbonyls by gaseous nitrogen dioxide are described under solid-solid and gas-solid reaction conditions, respectively. these methods are fast, simple and environmentally benign which do not require the use of any auxiliaries such as catalysts or...

n this work, computational fluid dynamics of the flow behavior in a cold flow of fluidized bed is studied. An improved finite volume based finite element method has been introduced to solve the two-phase gas/solid flow hydrodynamic equations. This method uses a collocated grid, where all variables are located at the nodal points. The fluid dynamic model for gas/solid two-phase flow is based on ...

the local solid flow structure of gas-solid bubbling fluidized bed was investigated to identify and characterize the particle clusters. extensive mathematical calculations were carried out using the energy-minimization multi-scale (emms) approach for evaluating cluster properties including the velocity, the size and the void fraction of clusters in the dense phase of the bed. the results showed...

in this paper, the development of a new potassium carbonateon alumina support sorbent prepared byimpregnating k2co3 with an industrial grade of al2o3 support was investigated. the co2 capturecapacity was measured using real flue gas with 8% co2 and 12% h2o in a fixed-bed reactor at atemperature of 65 °c using breakthrough curves. the developed sorbent showed an adsorptioncapacity of 66.2 mgco2/...