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Equilibrium adsorption data are reported for methane, ethane, and ethylene on titanosilicate ETS-10 zeolite for pressures up to 1000 kPa and temperatures of (280, 300, 315, 325, and 350) K. The data are modeled using Toth, unilan, and virial three-constant isotherms. Unconstrained and constrained optimization techniques have been applied to derive the model parameters. Henry's constant and limiting enthalpies of adsorption are deduced from the virial three-constant model and compared to the values derived for the Toth and unilan models. The saturation concentration is deduced on the basis of the assumption of 95% occupancy of the free zeolite voidage with adsorbed-state molecular volumes estimated from liquid densities.

Binary and ternary equilibrium adsorption data of methane, ethane, and ethylene on titanosilicate ETS-10 zeolites are reported at temperatures of 280 K and 325 K and pressures of 350 kPa and 700 kPa. The experimental data are modeled using the ideal adsorbed solution theory (IAST) in conjunction with the pure isotherms of Toth, Unilan, and Virial. The fit of this model to these data is satisfactory. Values of the relative adsorptivity calculated from the data and the IAST fits of the data show that the separation of methane from ethane or ethylene is extremely feasible at any conditions. Also, the separation of ethane from ethylene is highly favorable on ETS-10, particularly at low temperature. The removal of methane or ethane from the ternary mixture methane + ethane + ethylene is extremely easy at any operating conditions.

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In this paper, carbon nanotubes (CNTs) impregnated with iron oxide nanoparticles were employed for the removal of benzene from water. The adsorbents were characterized using scanning electron microscope, X-ray diffraction, BET surface area, and thermogravimetric analysis. Batch adsorption experiments were carried out to study the adsorptive removal of benzene and the effect of parameters such as pH, contact time, and adsorbent dosage. The maximum removal of benzene was 61% with iron oxide impregnated CNTs at an adsorbent dosage 100 mg, shaking speed 200 rpm, contact time 2 hours, initial concentration 1 ppm, and pH 6. However, raw CNTs showed only 53% removal under same experimental conditions. Pseudo-first-order kinetic model was found well to describe the obtained data on benzene removal from water. Initial concentration was varied from 1 to 200 mg/L for isotherms study. Langmuir isotherm model was observed to best describe the adsorption data. The maximum adsorption capacities were 987.58 mg/g and 517.27 mg/g for iron oxide impregnated CNTs and raw CNTs, respectively. Experimental results revealed that impregnation with iron oxide nanoparticles significantly increased the removal efficiency of CNTs.