Equilibrium and kinetics analysis of carbon dioxide capture using immobilized amine on a mesoporous silica

Abstract

in Wiley Online Library (wileyonlinelibrary.com).Thermogravimetric analysis is used to study the adsorption kinetics, equilibrium, and thermodynamics of CO 2 on immobilized polyethylenimine sorbent impregnated on a mesoporous silica over the range of 300-390 K and 5-100% CO 2 concentration. Adsorption isotherm models were fitted to the experimental data indicating that a change in adsorption mechanism occurred near 70 C. Below this temperature, the adsorption data followed the heterogeneous isotherms, while data taken at higher-temperatures followed isotherms for homogeneous surfaces. Heat of sorption was estimated to be 130 kJ/mole for the low-temperature regime, but this decreased to 48 kJ/mole above 70 C. The rate of CO 2 fractional uptake decreased as temperature increased. A phenomenological kinetic model was derived from the Weibull distribution function using a nucleation growth theory to describe the two-step process. The kinetic model was used to predict the uptake at different operating conditions and resulted in good agreement with experimental data. Published 2012 American Institute of Chemical Engineers AIChE J, 59: 923-935, 2013 Experiment MaterialsMethanol (reagent grade) and PEI (MW N 423) used in the preparation of the immobilized sorbents were purchased from Sigma-Aldrich Chemical and used without purification.

Catalytic Methanation of Carbon Dioxide by Active Oxygen Material CexZr1−xO2 Supported NiCo Bimetallic Nanocatalysts

“…In this regard, catalytic CO 2 methanation for the synthesis of fuels and valuable products has attracted considerable interest. 1,2 Numerous supported catalysts based on group VIII (noble metals) based supported catalysts have been tested for CO 2 methanation. [3][4][5][6][7] Notably, Ni catalysts supported on oxide supports were most widely applied attributed to their higher activity and selectivity.…”

CO2 Adsorption: Experimental Investigation and CFD Reactor Model Validation

“…More information is available on the adsorption process. Kinetic analysis for fluid bed adsorption in these sorbents was consistent with the TGA data [24,29]; however, the proposed nucleation and growth rate expressions are too numerically unstable to incorporate into computationally intensive CFD models.…”

“…Monazam et al [29] found that a mesoporous PEI based sorbent exhibits 2-dimensional nucleation growth diffusion controlled rates within this composite structure. The adsorption rate is controlled by the transport of CO 2 into the deeper PEI layers in the mesopores.…”

Bis (2‐mercapto‐ethyl) amine modification of macroporous sulfonic resin catalyst in bisphenol‐a synthesis

“…35 Meanwhile, 1/n < 1 also corresponds to a normal L-type Langmuir isotherm. 32,36 Moreover, the presence of solvent water also can decrease the heterogeneity of SSDB surface. 37 Based on these views, the Langmuir isotherm may be a better model which indicates the adsorbent surface is described by homogeneous adsorption sites.…”

“…32,33 The Langmuir model assumes monolayer surface coverage on equivalent sites. The Freundlich model, on the other hand, assumes a heterogeneous adsorption surface with sites that have different adsorption energies.…”