Carbon dioxide Adsorption

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Experimental, Kinetics and Isotherm Modeling of Carbon Dioxide Adsorption with 13X Zeolite in a fixed bed column

Experimental, Kinetics and Isotherm Modeling of Carbon Dioxide Adsorption with 13X Zeolite in a fixed bed column

conditions, including pressure and time, on adsorption capacity were investigated. The experimental conditions include constant temperature, the range of pressure of 1-9 bars, and the registration of adsorption capacity with the passage of time. Experimental data were adjusted with adsorption isotherm models including two- and three- parameter isotherms. In addition, the process was studied in terms of kinetic models; after the implementation of the experimental data with kinetic models, the speed of the process equations was obtained. The first-order equation was selected as the best kinetic model for this process. The results showed that the adsorption capacity of 13X was 71.5 mg/g at a pressure of 8 bars. Also, the results indicate that 13X has a high capacity at low pressures. With regard to achieved results for adsorption isotherm modeling, the adsorption isotherm followed the three parameters and, among the three-parameter models, Toth isotherm can interpret the process. Also, the results of the fixed bed indicate very high adsorbent selectivity to carbon dioxide adsorption, and there is little oxygen and nitrogen adsorption.

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Carbon Dioxide Adsorption Using Activated Carbon via Chemical Vapor Deposition Process

Carbon Dioxide Adsorption Using Activated Carbon via Chemical Vapor Deposition Process

amine scrubbing. However, this technology presents several disadvantages because amine scrubbing process requires high energy to operate and to regenerate solvent. Moreover, amine scrubbing process requires also special management from specialists. Other technologies developing aims to reduce the cost in the capture steps, including adsorption with activated carbon which is absorbent that has high adsorption capacity at ambient pressure, insensitiveness to moisture, easy regeneration, and low cost [4].

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Investigation of Carbon Dioxide Adsorption on Amino-Functionalized Mesoporous Silica

Investigation of Carbon Dioxide Adsorption on Amino-Functionalized Mesoporous Silica

Scanning electron microscopy (SEM) images of as- synthesized samples are shown in Figure 6. It can be seen that the well regular shape and morphology are the same in all of unfunctionalized and functionalized silica materials. This suggests the shape of particles is not changed and morphology of amino-functionalized SBA- 3 materials have remained intact after functionalization. The adsorption isotherms of CO 2 on

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A novel bismuth based metal organic framework for high volumetric methane and carbon dioxide adsorption

A novel bismuth based metal organic framework for high volumetric methane and carbon dioxide adsorption

but also for the design of new carbon capture systems. 3 MOF materials exhibit three- dimensional extended structures incorporating both large accessible pore volume and high internal surface area, which are key features for high capacity gas adsorption. They are often based upon divalent late first row transition metals [eg. Cu(II) and Zn(II)] and polycarboxylate ligands, and can show low framework densities (0.22-0.9 g cm -3 ) leading to high gravimetric gas uptakes. 4 Thus, a great deal of current effort is focused on the synthesis of low density MOFs by using elongated organic ligands 4a-c and/or light metal ions (e.g. Li, 5 Be, 6 Mg 7 ), in order to maximise and enhance gravimetric gas uptakes.

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Carbon Dioxide Adsorption on Single Walled Bamboo-Like Carbon Nanotubes (SWBCNT): A Computational Study

Carbon Dioxide Adsorption on Single Walled Bamboo-Like Carbon Nanotubes (SWBCNT): A Computational Study

Initially the bamboo-like carbon nanotubes (BCNTs) (12, 0) and (5,5) were constructed. These structures are primarily optimized classically using molecular mechanics method [27] with (mm+) force field [25], so as to get equilibrium geometry with the lowest possible strain energy. The classically optimized geometrical structures are further optimized by applying PM3 (Modified Neglect of Differential Overlap Parametric Method Number 3) semiempirical method [28] with in Restricted Hartee-Fock (RHF) formulation [29], sufficient to study carbon systems. Semi empirical methods serve as sufficient computational tools which can yield fast quantitative estimates for a number of properties [30]. Compared with ab initio or density functional methods, semi empirical calculations are much faster, typically by several order of magnitude [31]. All the structures were then subjected to conjugate gradient geometry optimization (Polak-Ribiere method [32], setting convergence limit 0.001 kcal-mol -1 and rms gradient 0.001 kcal (Å-mol) -1 . The optimized calculations were performed using Hyperchem 7.5 molecular modeling program [33]. The electron density difference has been calculated by semiemperical module [34] of the Quantumwise Atomix Toolkit 12.8.0, program [35].

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Carbon Dioxide Adsorption by Metal Organic Frameworks (Synthesis, Testing and Modeling)

Carbon Dioxide Adsorption by Metal Organic Frameworks (Synthesis, Testing and Modeling)

class of material in many industrial applications including gas separation, adsorption and storage processes [7], heterogeneous catalysis [8], pharmaceutical manufacturing processes and drug delivery [9]. Consequently, new generations of CPM that can be used for carbon dioxide adsorption with high capacity at atmospheric pressure are intensively investigated [10, 11]. In this regard, metal organic frameworks (MOFs) are one of the most promising porous materials due to their outstanding properties, including extremely their high surface area and pore volume as well as their high structural and chemical diversity, which can be achieved by changing the nature of the organic linkers and/or changing the connectivity of the inorganic moieties. In addition, the pore size of the MOF materials is tunable from the microporous, i.e., Angstrom, to the mesoporous (i.e., nanometer) scale [9, 12, 13]. MOFs are a new class of CPM composed of metal ions (or metal clusters) connected by means of multi-functional organic ligands, e.g., carboxylates, tetrazolate, sulfonates, etc., in order to form a three-dimensional structure [14]. Several MOFs have shown remarkable surface area, adsorption, selectivity and capacity for CO 2 capturing. According to the literature, one

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Promoting Effect of Inorganic Alkali on Carbon Dioxide Adsorption in Amine-Modified MCM-41

Promoting Effect of Inorganic Alkali on Carbon Dioxide Adsorption in Amine-Modified MCM-41

cycles were tested for all samples at the same conditions. Figure 6a shows the cycle performance of TEPA-modified samples. For MCM-41-TEPA, the weight of adsorption after one adsorption/desorption cycle slightly decreases, but the weight gains after each adsorption have no obvious decrease. This may due to that the N 2 flow removes some of TEPA molecules existing on the

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Gas adsorption in active carbons and the slit-pore model 1 : pure gas adsorption

Gas adsorption in active carbons and the slit-pore model 1 : pure gas adsorption

We describe procedures based on the polydisperse independent ideal slit-pore model, Monte Carlo simulation and density functional theory (a ‘slab-DFT’) for predicting gas adsorption and adsorption heats in active carbons. A novel feature of this work is the calibration of gas-surface interactions to a high surface area carbon, rather than to a low surface area carbon as in all previous work. Our models are used to predict the adsorption of carbon dioxide, methane, nitrogen, and hydrogen up to 50 bar in several active carbons at a range of near-ambient temperatures based on an analysis of a single 293 K carbon dioxide adsorption isotherm. The results demonstrate that these models are useful for relatively simple gases at near-critical or supercritical temperatures.

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Gas adsorption in active carbons and the slit-pore model 2 : mixture adsorption prediction with DFT and IAST

Gas adsorption in active carbons and the slit-pore model 2 : mixture adsorption prediction with DFT and IAST

We describe procedures based on the polydisperse independent ideal slit-pore model, Monte Carlo simulation and density functional theory (a ‘slab-DFT’) for predicting gas adsorption and adsorption heats in active carbons. A novel feature of this work is the calibration of gas-surface interactions to a high surface area carbon, rather than to a low surface area carbon as in all previous work. Our models are used to predict the adsorption of carbon dioxide, methane, nitrogen, and hydrogen up to 50 bar in several active carbons at a range of near-ambient temperatures based on an analysis of a single 293 K carbon dioxide adsorption isotherm. The results demonstrate that these models are useful for relatively simple gases at near-critical or supercritical temperatures.

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Modeling of Adsorption Compression for Supercritical Carbon Dioxide

Modeling of Adsorption Compression for Supercritical Carbon Dioxide

This paper is reporting new finding in the field of adsorbate-adsorbate interaction for supercritical carbon dioxide adsorption by One-Kondo model analysis. Adsorption isotherms for supercritical carbon dioxide on activated carbon Filtrasorb 400 and on zeolite 13X have been evaluated and shown to demonstrate adsorption compression phenomenon at high pressure end just as in subcritical systems. Experimental isotherms for adsorption of supercritical carbon dioxide are plotted in Ono-Kondo coordinates with the Henry’s constant estimated based on results of modeling as well as calorimetric and chromatographic measurements. The linear sections of the results show the range of applicability of the classical Ono-Kondo model with constant energies of interactions. The slopes of these linear sections represent values and signs of these energies: negative slopes indicate repulsive interactions in adsorbed phase due to adsorption compression. Switching interactions from attractive to repulsive with an increase in the pressure for supercritical adsorption suggests that adsorbed phase has two regions. One is an attractive region at low-pressures and the other is a repulsive region at high pressures. It can be indicated that the shape of isotherms in Ono-Kondo coordinates can help to understand adsorbate-adsorbate energies; the slope of the line in Ono-Kondo coordinates gives the sign and magnitude of the energy as a function of adsorbate density.

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Macrocyclic complexes and their use as electrocatalysts for the electrochemical reducation of carbon dioxide

Macrocyclic complexes and their use as electrocatalysts for the electrochemical reducation of carbon dioxide

The next step was to look at the different solvents using the HMDE. Here it is only possible to investigate the Ni(n/I) redox couple since the mercury oxidises above 0 V vs SCE. The Ni(II/I) is observed in all solvents although the peak separation varies and in most cases does not approach the ideal 59 mV value (see Section 2.1.2). The actual kinetics of the electron transfer in organic solvents is slow while in aqueous or mixed solvents the system is almost Nemstian. When carbon dioxide is bubbled into the solution there is a change in the behaviour of the Ni(II/I) redox couple. The current associated with the reduction increases and the reversibility is lost. The most obvious feature in the catalytic current is that the peak potential shifts to more positive potentials in protic solvents. This observation is supported by other work, and reflects the need for protons in the reduction. Although catalysis is observed in MeCN (an aprotic solvent), this is possibly due to trace amounts of water allowing a small amount of catalysis at a highly negative potential - quite close to that for carbon dioxide reduction at a bare mercury electrode. With a limiting amount of protons (in 9:1 MeCN/H 2 0 ) then there is a higher current associated with the reduction and the potential shifts more positive. The best and lowest potential for carbon dioxide occurs in water, where the reduction occurs at -1.40 V, a potential lower than the reduction potential for the Ni(n/I).

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Control of carbon dioxide and other emissions from diesel operated engines using activated charcoal

Control of carbon dioxide and other emissions from diesel operated engines using activated charcoal

adsorb many microorganism, plants and animals. However, emissions and removal of carbon dioxide by this natural process tend to balance. Since the industrial revolution began around 1750, human activity have contributed substantially to by adding carbon dioxide and other heat trapping gases to atmosphere. Rajadurai et al. (2015) the efforts of humans to gain more energy output is dearly costing the entire planet in phase of carbon dioxide, emission of this gas can be controlled by implementing some major changes at the source of emissions. An inventive trend of using a chamber at the tailpipe of an exhaust system, which traps and stores the carbon dioxide from the exhaust gases. Modified charcoal made of coconut trunk and stem is used to trap and store carbon dioxide from the exhaust gases. The theory of storage and using of carbon dioxide can be helpful in many other industrial which uses carbon dioxide for many other purposes. MuhammedZaman and Jay Hyung Lee, et al. (2007) the total content of carbon dioxide emissions from diesel operated engine is lesser than that of petrol engine, in numerical terms its 27% and 17% petrol and diesel respectively. When the engine displacement is high then the consumption of fuel is also high. Catalytic convertor is another major part which plays an important role in the exhaust system, the process of oxidation and reduction of on dangerous gases emitted from the exhaust gases, there are

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Influence of Nitrogen on Structure, Guest Distribution and Hydrate Formation Conditions of the Mixed CO 2CH4 and CO 2CH4N2 Gas Hydrates

Influence of Nitrogen on Structure, Guest Distribution and Hydrate Formation Conditions of the Mixed CO 2CH4 and CO 2CH4N2 Gas Hydrates

solution theory of clathrate hydrate for multiple cage occupancy, host lattice relaxation and guest- guest interactions [34-38]. With this goal there have been determined the dependencies of the compositions of the gas hydrates formed from methane + carbon dioxide, nitrogen + carbon dioxide binary gas mixtures and methane + carbon dioxide + nitrogen ternary gas mixtures as well as of the formation conditions of these hydrates in dependence on temperature and pressure for different compositions of the gas phase.

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Carbonic Gas Randomness Effect on Reinforced Concrete Carbonation

Carbonic Gas Randomness Effect on Reinforced Concrete Carbonation

in the carbonation process. The reaction of hydrated composed of concrete with carbon dioxide induces pro- duction of water, more the amount of carbon dioxide released into the pores is greater, more the quantity of water formed during carbonation is important, this train- ing will also disrupt the process in the direction of slower reactions and increase the carbonation time.

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Converting Carbon Dioxide to Butyrate with an Engineered Strain of Clostridium ljungdahlii

Converting Carbon Dioxide to Butyrate with an Engineered Strain of Clostridium ljungdahlii

IMPORTANCE The development of a microbial chassis for efficient conversion of carbon dioxide directly to desired organic prod- ucts would greatly advance the environmentally sustainable production of biofuels and other commodities. Clostridium ljung- dahlii is an effective catalyst for microbial electrosynthesis, a technology in which electricity generated with renewable technolo- gies, such as solar or wind, powers the conversion of carbon dioxide and water to organic products. Other electron donors for C. ljungdahlii include carbon monoxide, which can be derived from industrial waste gases or the conversion of recalcitrant bio- mass to syngas, as well as hydrogen, another syngas component. The finding that carbon and electron flow in C. ljungdahlii can be diverted from the production of acetate to butyrate synthesis is an important step toward the goal of renewable commodity production from carbon dioxide with this organism.

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Carbon Dioxide Reduction in Gasoline Engine - A Comparative Study

Carbon Dioxide Reduction in Gasoline Engine - A Comparative Study

ABSTRACT: We have undertaken a study to artificially reduce carbon dioxide using different catalysts in a gasoline passenger caras our continued effort to control carbon dioxide in the atmosphere. Carbon dioxide absorption/adsorption efficiencyfrom the exhaust gas stream using different catalysts such as activated charcoal, activated alumina, ZSM-5 zeolite and activated ZSM-5 zeolite shows a clear trend and dependency on the mass flow rate and surface properties of catalysts. The CO 2 absorption efficiency of these catalysts aremeasured at two different

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Enhancement of the dissolution rate and bioavailability of fenofibrate by a melt-adsorption method using supercritical carbon dioxide

Enhancement of the dissolution rate and bioavailability of fenofibrate by a melt-adsorption method using supercritical carbon dioxide

In this study, an amorphous fenofibrate formulation was successfully prepared by melt adsorption using supercriti- cal CO 2 . Fenofibrate adsorbed onto Neusilin UFL2 exists in an amorphous form and shows an enhanced dissolution rate and bioavailability. The enhancement in oral absorp- tion of fenofibrate adsorbed onto Neusilin UFL2 was attributed to a higher dissolution rate as a result of the amorphous nature and reduction of particle size. This study demonstrates the usefulness of the supercritical method for improving the bioavailability of fenofibrate. Furthermore, the melt adsorption method using supercritical CO 2 does not require organic solvents and can be used to improve the bioavailability of other poorly water-soluble drugs with low melting points.

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Gaussian Process Prediction Model to Estimate Excess Adsorption Capacity of Supercritical CO 2

Gaussian Process Prediction Model to Estimate Excess Adsorption Capacity of Supercritical CO 2

many recent scholars[12,20,22]. These studies commonly include monolayer, multilayer and potential models. The typical monolayer models are the Toth, Langmuir, T-P, and Extended-Langmuir models. The multilayer approach includes different forms of BET models and also the potential model consists of D-R model, its modification and upgraded D-A model. These approaches have been utilized for estimation of adsorption of supercritical CO 2 . However, they have significant drawbacks including

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Adsorption equilibrium of carbon dioxide on ammonia modified activated carbon

Adsorption equilibrium of carbon dioxide on ammonia modified activated carbon

The separation and purification of gas mixtures by adsorp- tion is a potential option because of its ease of operation, high adsorption capacity, minimal environmental impact, low cost, and efficient recovery of the solute compared to conven- tional absorption with liquid solvents (Cavenati et al., 2004; Houshmand et al., 2012; Serna-Guerrero et al., 2010a). Par- ticularly, pressure-swing adsorption (PSA) has a number of attractive characteristics, such as its applicability over a rela- tively wide range of temperature and pressure conditions, its low energy requirements, and its low capital investment costs (Delgado et al., 2006; Mutasim and Bowen, 1991). The last three decades have seen a tremendous growth in research into and commercial applications of CO 2 removal from various flue-

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Adsorption of carbon dioxide and methane on alkali metal exchanged silicoaluminophosphate zeolite

Adsorption of carbon dioxide and methane on alkali metal exchanged silicoaluminophosphate zeolite

Ion exchanged was carried out in a two-step procedure using lithium and potassium cations. Characterization o f the prepared materials was carried out using X- ray diffraction (XRD) analysis to determine the crystallinity o f the prepared materials. Field Emission Scanning Electron Microscopy (FESEM) analysis to observe/visualize the topographical details and/or changes on the surface. Fourier Transform Spectroscopy (FTIR) analysis to identify the attachment o f functional groups on the samples and their effect after ion exchange. N 2 adsorption studies was performed to

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