Heats of Adsorption from Liquid Solutions and from Pure Vapor Phase:  Adsorption of Thiophenic Compounds on NaY and 13X Zeolites

Ma, Liping; Yang, Ralph T.

doi:10.1021/ie070336i

Cited by 13 publications

(5 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Also, we found that transition metal ion exchanged zeolites exhibit excellent properties for the adsorption of the sulfur-containing compounds and the measured adsorption strength for each mole sulfur adsorbed on Y zeolites is in the order of CuY > NiY > NaY because of the formation of the π -complexes (Jiang and Ng 2006). Recently, our results on the heat of adsorption are further confirmed by Yang and coworkers based on the calculation by using the ClausiusClapeyron equation and according to the measurement of the heats of adsorption both from liquid solutions and from pure vapor phase (Ma and Yang 2007b).…”

Section: Introductionsupporting

confidence: 81%

Production of low sulfur diesel fuel via adsorption: an equilibrium and kinetic study on the adsorption of dibenzothiophene onto NaY zeolite

Jianzhun

2010

Adsorption

View full text Add to dashboard Cite

The adsorption of dibenzothiophene (DBT) in hexadecane onto NaY zeolite has been studied by performing equilibrium and kinetic adsorption experiments. The influence of several variables such as contact time, initial concentration of DBT and temperature on the adsorption has been investigated. The results show that the isothermal equilibrium can be represented by the Langmuir equation. The maximum adsorption capacity at different temperatures and the corresponding Langmuir constant (K L ) have been deduced. The thermodynamic parameters ( G 0 , H 0 , S 0 ) for the adsorption of DBT have also been calculated from the temperature dependence of K L using the van't Hoff equation. The value of H 0 , S 0 are found to be −30.3 kJ mol −1 and −33.2 J mol −1 K −1 respectively. The adsorption is spontaneous and exothermic. The kinetics for the adsorption process can be described by either the Langmuir model or a pseudo-second-order model. It is found that the adsorption capacity and the initial rate of adsorption are dependent on contact time, temperature and the initial DBT concentration. The low apparent activation energy (12.4 kJ mol −1 ) indicates that adsorption has a low potential barrier suggesting a mass transfer controlled process. In addition, the competitive adsorption between DBT, naphthalene and quinoline on NaY was also investigated. NomenclatureDBT dibenzothiophene t contact time, min c 0 initial concentration of adsorbate in the solution, mmol L −1 c t the concentration of adsorbate at contact time t, mmol L −1 c e equilibrium concentration of adsorbate in the solution, mmol L −1 c DBT the concentration of DBT, mmol L −1 k 0 temperature independent factor, g mmol −1 min −1 k 2 pseudo-second-order rate constant, g mmol −1 min −1 k ads adsorptive constant, L g −1 min −1 k d desorptive constant, mmol g −1 min −1 K L Langmuir constant, L mmol −1 q e adsorptive amount of adsorbate after equilibrium, mmol g −1 q L a solution of the second-order polynomial expression, mmol g −1 q m adsorptive amount of adsorbate to its maximum, mmol g −1 q t adsorptive amount of adsorbate at time t, mmol g −1 θ dimensionless ratio of coverage of the surface of adsorbent v 0 initial adsorptive rate, mmol g −1 min −1 v ads rate of adsorption, mmol g −1 min −1 v d rate of desorption, mmol g −1 min −1 v t rate of adsorption at time t, mmol g −1 min −1 V the volume of solution, L W the mass of adsorbent, g R 2 regression coefficient E a activation energy of adsorption, kJ mol −1 550 Adsorption (2010) 16: 549-558 R g the universal gas constant, 8.314 J mol −1 K −1 T temperature,°C T K temperature in Kelvin, K G 0 Gibbs free energy, kJ mol −1 H 0 enthalpy, kJ mol −1 S 0 entropy, J mol −1 K −1

show abstract

Section: Introductionsupporting

confidence: 81%

Production of low sulfur diesel fuel via adsorption: an equilibrium and kinetic study on the adsorption of dibenzothiophene onto NaY zeolite

Jianzhun

2010

Adsorption

View full text Add to dashboard Cite

show abstract

“…The micropore volumes are 0.269 cm 3 /g for NaX and 0.244 cm 3 /g for NaY based on the DubininÀAstakhov (DA) method. The micropore volume for our NaX sample is close to the value of 0.26 cm 3 /g reported for a commercial faujasite-type zeolite (13X) in pellet form 33 but is less than reported values of 0.30 cm 3 /g for the sample in powder form 34 and 0.32 cm 3 /g in crystal form. 35 For NaY zeolite, our sample has a lower micropore volume compared to reported values of 0.30 cm 3 /g for the sample in powder form 34 and 0.36 cm 3 /g for a lab-synthesized NaY.…”

Section: ' Introductionsupporting

confidence: 80%

High Pressure Excess Isotherms for Adsorption of Oxygen and Nitrogen in Zeolites

et al. 2011

View full text Add to dashboard Cite

High-pressure oxygen is an integral part of fuel cell systems, many NASA in situ resource utilization concepts, and life support systems for extravehicular activity. Due to the limited information available for system designs over wide ranges of temperature and pressure, volumetric methods are applied to measure adsorption isotherms of O(2) and N(2) on NaX and NaY zeolites covering temperatures from 105 to 448 K and pressures up to 150 bar. Experimental data measured using two apparatuses with distinctly different designs show good agreement for overlapping temperatures. Excess adsorption isotherms are modeled using a traditional isotherm model for absolute adsorption with a correction for the gas capacity of the adsorption space. Comparing two models with temperature-dependent coefficients, a virial isotherm model provides a better description than a Toth isotherm model, even with the same number of parameters. With more virial coefficients, such as a cubic form in loading and quadratic form in reciprocal temperature, the virial model can describe all data accurately over wide ranges of temperature and pressure.

show abstract

“…The adsorption isotherms of thiophene were calculated at the low-concentration range of thiophene for modeling the sulfur compound in oil fuels . As a comparison, the adsorption isotherms from experiments for the thiophene/ n -octane binary mixture on the NaX and NaY are also shown in Figure . The simulated results underpredicted the adsorption isotherms of thiophene in the same type of zeolite.…”

Section: Resultsmentioning

confidence: 99%

Monte Carlo Simulations of Adsorption of Thiophene/Benzene in NaX and NaY Zeolites from Model Fuel

Zhong

et al. 2020

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

The process of adsorptive desulfurization requires sorbents to have high adsorption capacity and selectivity for thiophene in contrast to aromatics or alkanes. We investigated the adsorption of thiophene, benzene, and their mixtures in the presence of n-octane by the sodium-exchanged FAU zeolite using the grand canonical Monte Carlo simulations. The adsorption isotherms were computed and compared with available experimental data. The simulation results show that the change in the Si/Al ratio of zeolite may cause significant differences in adsorption selectivity, which was also observed by experiments. The NaX zeolite shows a higher adsorption selectivity than the NaY zeolite. The location of cations in the zeolites results in a change of pore size and creates an additional type of adsorption site, which subsequently results in different adsorption selectivities between thiophene and benzene in model fuel.

show abstract

Heats of Adsorption from Liquid Solutions and from Pure Vapor Phase: Adsorption of Thiophenic Compounds on NaY and 13X Zeolites

Cited by 13 publications

References 52 publications

Production of low sulfur diesel fuel via adsorption: an equilibrium and kinetic study on the adsorption of dibenzothiophene onto NaY zeolite

Production of low sulfur diesel fuel via adsorption: an equilibrium and kinetic study on the adsorption of dibenzothiophene onto NaY zeolite

High Pressure Excess Isotherms for Adsorption of Oxygen and Nitrogen in Zeolites

Monte Carlo Simulations of Adsorption of Thiophene/Benzene in NaX and NaY Zeolites from Model Fuel

Contact Info

Product

Resources

About