Carbon Dioxide Adsorption Capacity Research Articles

Efficiency increase in hypercrosslinked polymer based on polystyrene in CO2 adsorption process

In this investigation, a hypercrosslinked polymer based on polystyrene as an adsorbent was used for CO2 adsorption. Design of experiment with response surface methodology is considered to optimize the synthesis parameters for obtaining the maximum carbon dioxide adsorption capacity. The independent parameters including the crosslinker amount (mmol), synthesis time (h) and catalyst type (FeCl3 and AlCl3) and adsorption capacity (mg/g) are considered as the dependent parameter in design of experiment method. The optimum values of crosslinker amount, synthesis time, and catalyst type to maximize adsorption capacity achieved 17.7 mmol, 14.6 h, and FeCl3, respectively. Additionally, isotherm and kinetic modeling were carried out to determine the adsorbent behavior. The results showed that Hill and Elovich models have a better precision between other isotherm and kinetic models. Finally, thermodynamic modeling was accomplished using the optimized adsorbent and the results show that physisorption is the main of CO2 adsorption by polystyrene-based adsorbent. The values of − 13.498 kJ/mol, − 0.018 kJ/mol.K, and − 8.224 kJ/mol were obtained for enthalpy differences, entropy differences, and Gibbs free energy change at 293 K and 5 bar, respectively.

Aminopropyltriethoxysilane functionalized MCM-41 and SBA-15 nanostructured materials for carbon dioxide adsorption

The design of effective CO2 capture materials is a current challenge. Here, we report the synthesis of aminosilanes-functionalized MCM-41 and SBA-15 materials with high efficiency toward carbon dioxide adsorption. The functionalization of the mesoporous silicas involves a post-synthesis method by impregnation with 3-aminopropyltriethoxysilane. The carbon dioxide adsorption capacities for the samples were carried out under ambient pressures. The results evidenced that aminosilanes with a terminal amine were functionalized through covalent coupling of this group onto the channels' surface in the ordered mesoporous silica. It means that the amine is anchored on the surface of the largest pores of the MCM-41 and SBA-15 supports. The Lagergren kinetic model evidenced the enhanced carbon dioxide adsorption capacity and stability of the functionalized ordered mesoporous molecular sieves.

Empty cotton boll crop-residue and plastic waste valorization to bio-oil, potassic fertilizer and activated carbon – A bio-refinery model

Empty cotton boll and plastic waste (@ 5% w/w) were slow pyrolyzed in a fixed bed pilot scale reactor at 500 °C in vacuum. The proposed bio-refinery model involves: (1) application of bio-oil as alternative fuel in existing engine facility, (2) water leaching of bio-char followed by synthesis of potassic fertilizer, and (3) chemical activation of spent char to porous carbon. Thorough investigation of moisture free bio-oil fuel properties supported its applicability in the engine. Moisture free bio-oil was blended with commercial gasoline in proportions of 10–30% (v/v). The effect of engine functioning parameters: compression ratio, engine load and blend proportion on engine performance and emission was optimized using response surface methodology. Almost 93 wt% of water leachable potassium available in the bio-char was leached out via two stage counter current leaching. Route of selective precipitation using tartaric acid converted ∼98 wt% of potassium available in leachate to potassium nitrate. Porous carbon with surface area of 1381.40 m2/g was derived via chemical activation of spent char at 700 °C in nitrogen atmosphere. The porous carbon showed carbon-dioxide adsorption capacity of 5.1 mmol/g at 25 °C and 1 atm pressure.

New Porous Silicon-Containing Organic Polymers: Synthesis and Carbon Dioxide Uptake

The design and synthesis of new multifunctional organic porous polymers has attracted significant attention over the years due to their favorable properties, which make them suitable for carbon dioxide storage. In this study, 2-, 3-, and 4-hydroxybenzaldehyde reacted with phenyltrichlorosilane in the presence of a base, affording the corresponding organosilicons 1–3, which further reacted with benzidine in the presence of glacial acetic acid, yielding the organic polymers 4–6. The synthesized polymers exhibited microporous structures with a surface area of 8.174–18.012 m2 g−1, while their pore volume and total average pore diameter ranged from 0.015–0.035 cm3 g−1 and 1.947–1.952 nm, respectively. In addition, among the synthesized organic polymers, the one with the meta-arrangement structure 5 showed the highest carbon dioxide adsorption capacity at 323 K and 40 bar due to its relatively high surface area and pore volume.

Enhancement of CO2 Adsorption Containing Zinc-ion-exchanged Zeolite NaA Synthesized from Rice Husk Ash

Carbon dioxide is main causes the greenhouse effect and it contributes to global warming. Zeolite NaA is an excellent adsorbent among other materials but its potential as a carbon dioxide adsorption still needs to be developed. Therefore, this research was to synthesize zeolite NaA from rice husk ash under different temperatures and crystallization times. The synthesized zeolite NaA was modified with zinc by an ion exchange method. Adsorbents were tested for the carbon dioxide adsorption at different operating temperatures and flow rates. The results showed that the zeolite NaA was successfully synthesized from rice husk ash under optimal conditions of the crystallization temperature at 333.15 K and time for 2 h. The zeolite NaA can be synthesized at low crystallization temperature and time resulted in this adsorbent has low cost while achieving high efficiency. The results of zeolite NaA modification with zinc playing a key role to increase the BET surface area, micropore volume and total pore volume resulted in an increase of carbon dioxide adsorption capacity. High carbon dioxide adsorption at 89.08% with the operating temperature at 573.15 K and carbon dioxide flow rate of 1 L/h were shown with 5 wt.% zeolite NaA.

Co-valorization of delayed petroleum coke – palm kernel shell for activated carbon production

In this study, a binary mixture of petroleum coke and palm kernel shell had been investigated as potential starting materials for activated carbon production. Single-stage potassium carbonate (K2CO3) activation under nitrogen (N2) atmosphere was adopted in this research study. Effect of several operating parameters that included the impregnation ratio (1−3 wt./wt.), activation temperature (600−800 °C), and dwell time (1−2 hrs) were analyzed by using the Box-Behnken experimental design. Influence of these parameters towards activated carbon yield (Y1) and carbon dioxide (CO2) adsorption capacity at an atmospheric condition (Y2) were investigated. The optimum conditions for the activated carbon production were attained at impregnation ratio of 1.75:1, activation temperature of 680 °C, and dwell time of 1 h, with its corresponding Y1 and Y2 is 56.2 wt.% and 2.3991 mmol/g, respectively. Physicochemical properties of the pristine materials and synthesized activated carbon at the optimum conditions were analyzed in terms of their decomposition behavior, surface morphology, elemental composition, and textural characteristics. The study revealed that the blend of petroleum coke and palm kernel shell can be effectively used as the activated carbon precursors, and the experimental findings demonstrated comparable CO2 adsorption performance with commercial activated carbon as well as that in literatures.

Nanoporous activated biocarbons with high surface areas from alligator weed and their excellent performance for CO2 capture at both low and high pressures

We report on the preparation of highly efficient nanoporous activated biocarbons (NABs) from alligator weed with high surface areas, pore volumes, tunable microporosity and oxygen functional groups for carbon dioxide adsorption. Alligator weed is converted into a non-porous carbon at 600 °C, which is then activated using potassium hydroxide at 800 °C through liquid state chemical activation. The simple synthesis provides easy control over experimental conditions which are carefully manipulated to yield the optimized material with a high specific surface area (3106 m2 g−1) and a high pore volume (1.62 cm3 g−1). It is also demonstrated that the microporosity and surface oxygen functional groups can be controlled with a simple adjustment of the amount of potassium hydroxide. Owing to the excellent textural features, the optimized material adsorbed a high amount of carbon dioxide at 0 °C (30.4 mmol g−1), 10 °C (27.7 mmol g−1) and 25 °C (23.3 mmol g−1) at a high pressure of 30 bar, which is much higher than that of activated carbon, ordered nanoporous carbon and mesoporous silicas. It also shows a low value of isosteric heat of adsorption (~22 kJ mol−1) that indicates physical adsorption. The material with high microporosity shows impressive carbon dioxide adsorption capacity of 6.4 mmol g−1 at 0 °C and low pressure of 1 bar. The high and low pressure carbon dioxide adsorption values indicate that the materials are promising adsorbents for carbon dioxide and the physical adsorption implies an easier regeneration. These findings suggest that biomass alligator weed can be utilized for devising advanced nanomaterials with high porosity for carbon capture.

Synthesis, characterization and gas adsorption analysis of solvent dependent Zn-BTC metal organic frameworks

ABSTRACT Multidentate 1,3,5-benzene tricarboxylic acid copolymerizes with Zinc to form framework with rigid porosity for gas adsorption application. One of the barriers in commercialization of these MOFs for gas adsorption application is the usage of costly solvents and this research is based on identifying the effect of solvents on zinc and 1,3,5-benzene tricarboxylic acid-based MOFs, their gas adsorption capacities and costs. All the MOFs prepared were characterized and further tested for carbon dioxide adsorption capacities. The results highlight that the textural properties of prepared MOFs depend largely on solvents utilized and high surface area MOFs have high adsorption capacity. Also the carbon dioxide adsorption capacity of MOFs prepared using DMF showed better adsorption as compared with the one prepared with Ethanol:De-ionized water. This research also elaborates the fact that there is a possibility of replacing the expensive solvents for Zn-BTCs synthesis with low-cost solvents without compromising the gas adsorption performance.

Thermodynamic effects of cycling carbon dioxide injectivity in shale reservoirs

Carbon dioxide injectivity has always been considered as one of the optimum enhanced recovery techniques, especially in tight reservoirs regarding the feasible mobilization of gas through porous media. To have a better understanding of carbon dioxide injectivity performances, it would be of importance to consider crucial parameters and their effects on the carbon dioxide adsorption and oil recovery factor. In this paper, the profound impact of crucial parameters such as temperature, pressure, carbon dioxide soaking time, and core stimulation on the oil recovery enhancement were investigated. Moreover, the considerable influence of pressure and temperature on the carbon dioxide adsorption capacity storage were performed and analyzed. According to the result of this experiment, temperature increase led to reducing carbon dioxide storage capacity, which has a reverse pattern with oil recovery factor by increasing temperature. When the core samples were unstimulated, the oil recovery factor has higher than stimulated core samples. Furthermore, pressure increase resulted in the carbon dioxide storage capacity enhancement, which has a similar increase pattern with oil recovery factor by increasing pressure. The maximum carbon dioxide storage capacity is 91% and 90% at the pressure of 1500 psi and temperature of 20 °C respectively. Soaking time rising between oil and carbon dioxide led to producing more oil volume.

Defects and Conductive Nitrogen-Carbon Framework Regulated ZnInOx Nanosheets for Boosting CO2 Electrocatalytic Reduction

Reducing the dimension and creating defects are effective approaches to increase the active sites of catalysts. Herein, the defective ZnInOx/NCF catalyst was successfully prepared under the inspiration of 3D porous structure of melamine sponge. The functionalized ZnInOx/NCF features larger electrochemical active surface area, higher carbon dioxide adsorption capacity and faster charge transfer rate, which is conducive to electrochemical reduction CO2 to HCOO-. ZnInOx/NCF exhibits the highest Faradaic efficiency (FE) of 90.5% for HCOO- production at a moderate overpotential of 0.9 V with a good stability. The study of catalysts structure and reaction mechanisms demonstrate that the superior activity is attributed to the synergistic effect among the MS-derived NCF conductive matrix and the reduced dimensionality and abundant defects of ZnInOx.

Improved CO2 adsorption onto chemically activated spherical phenol resin

This study reveals the significant improvement of adsorption capacity of carbon dioxide (CO2) onto spherical phenol resin (PR) activated by potassium hydroxide (KOH), designated KOH6-PR. Experiments were performed using a gravimetric adsorption measurement instrument for the wide range of temperatures 20–70 °C and pressure up to 7 MPa. The measured excess uptakes were found steadily increase up to 5.7 MPa at 25 °C and reached the value of 1.69 g g−1. After that, a declining trend was observed, which is corrected by the adsorbed gas density and pore volume of the adsorbent. The measured isotherm data were examined using the modified Dubinin-Astakhov (D-A) model, and the Tóth model within a 3.7 % root mean square deviation (RMSD). The maximum CO2 adsorption capacity of microporous KOH6-PR was found 2.36 cm3 g−1 using the modified d-A model. The adsorption capacity showed more than 50 % enhancement compared to the widely used Maxsorb III. The average value of heat of adsorption is calculated employing the Clausius-Clapeyron and the modified d-A equations. The cooling performance of an adsorption cycle using the KOH6-PR/CO2 pair is predicted. These analyses are necessary for utilizing CO2 as a refrigerant in adsorption heat pumps and gas storage applications.

Nitrogen and sulfur-enriched porous bithiophene-melamine covalent organic polymers for effective capture of CO2 and iodine

Low-cost bithiophene and melamine were constructed into a new nitrogen and sulfur-enriched organic framework (TPFM) by one-pot Shiff-base type reaction without any catalysts and post-treatment procedure. The as-synthesized TPFM exhibits the sphere-like morphology and mesopore-dominated porous structure with 611.3 m2 g−1 surface area. Profiting from the pore channels with abundant –NH groups on TPFM, it presents efficient carbon dioxide adsorption capacity with 77.5 cm3 g−1 (about 16 wt%) at 273 K. The donated lone pair electrons in S and N atoms on TPFM contributed to its fast and efficient iodine adsorption capacities of 293.3 mg g−1 in cyclohexane solution within several minutes.

Preparation of new carbon molecular sieves for optimized carbon dioxide adsorption and product yield

Chemical vapor deposition (CVD)from methane on activated carbon prepared by zinc chloride activation of residue extracted from sunflower seeds, has been optimized to produce carbon molecular sieves using the Taguchi method, targeted at achieving maximum CO2 adsorption capacity and an increased product yield. The carbon molecular sieves were characterized by N2 adsorption, CO2 adsorption, elemental analysis, SEM and FTIR. The CO2 adsorption capacities were measured at 1 bar/273 K. The optimized carbon molecular sieve with the highest product yield of 91 wt.% had amaximum CO2 adsorption of 2.6228 mmol g-1. Both nitrogen and oxygen surface functional groups and the narrow micropores are crucial for CO2 adsorption. The Taguchi method is a powerful tool to simultaneously optimize the carbon dioxide adsorption capacity and the yield of carbon molecular sieves.

Role of amine-impregnated activated carbon in carbon dioxide capture

ABSTRACT In this work, two types of amine-impregnated activated carbons have been prepared from green coconut shell: Monoethanol amine-impregnated activated carbon (M-AC) and Diethanol amine-impregnated activated carbon (D-AC). Carbon dioxide (CO2) adsorption was determined by a batch adsorption analysis. Effects of the time and relative pressure on CO2 adsorption capacity of amine-impregnated activated carbon were studied. From the result, it has been observed that amine-impregnated activated carbons have higher adsorption capacity for CO2 although there is a decrease in the surface area of activated carbon due to amine impregnation. Among the two impregnated amine activated carbon and monoethanol amine-impregnated activated carbon, impregnation ratio 0.4 shows the highest carbon dioxide adsorption capacity i.e. 36.84 mg g−1.

Examination of adsorption behaviors of carbon dioxide and methane in oxidized coal seams

The injection of CO2 to enhance coalbed methane recovery is a promising way for carbon dioxide sequestration and exploitation of coal-bed methane. In this work, molecular simulation is conduced to investigate the adsorption and diffusion behaviors of carbon dioxide and methane in coal seams. The effect of coal oxidation is further evaluated. The adsorption amount and isosteric heat of CH4 and CO2 in mono-component and binary mixture are compared. The results reveal that the partial oxidation of coal will weaken the carbon dioxide adsorption capacity and isosteric heat. In contrast to the mono-component, the CH4 adsorption in a binary mixture is greatly reduced owing to the presence of CO2. Meanwhile, the effect of coal oxidation on gas diffusion is also examined. The results demonstrate that the coal oxidation will promote the gas diffusion.

Soil with high porosity as an excellent carbon dioxide adsorbent carbon-rich soil as an effective adsorbent for carbon dioxide

Carbon dioxide, a type of greenhouse gases has drawn world wide’s attention as major contributors to global warming and climate change. Thus, several methods have been developed to mitigate this problem such as through adsorption. There are numerous types of adsorbents available, for instance is carbon-based adsorbent that can be synthesised from various type of biomass as reported in previous studies. However, there are very few studies used soil as an adsorbent for gases. Soils are porous medium developed in the uppermost layer of Earth’s crust which are available in several forms, abundance and cheap. In this study, three types of carbonised soils were used as carbon-based adsorbent to investigate its adsorption capacity for carbon dioxide. Influence of moisture content in this study is negligible as it is too low. Due to the nature of raw materials used, ash content for all sample was incredibly high which almost all exceeded 90%. Determination of densities by pycnometer showed that carbonised soil 2 has the lowest particle and bulk density of 2.4802 g/cm3 and 0.5248 g/cm3 respectively. Then the adsorption capacity of each sample was determined by sorption measuring instrument with magnetic suspension balance. Results showed that carbonised soil 2 with high surface area, pore volume, and small pore size has the highest adsorption capacity of 6.4 mg/g at 25 ˚C under atmospheric pressure. Therefore, soils exhibit prominent potential to be developed as carbon dioxide adsorbent with desirable properties.

Probing the bent bonds in cyclopropane systems for gas storage and separation process: A computational study.

The hydrogen, carbon dioxide, and carbon monoxide gas adsorption and storage capacity of lithium-decorated cyclopropane ring systems were examined with quantum chemical calculations at density functional theory, DFT M06-2X functional using 6-31G(d) and cc-pVDZ basis sets. To examine the reliability of M06-2X DFT functional, a few representative systems are also examined with complete basis set CBS-QB3 method and CCSD-aug-cc-pVTZ level of theory. The cyclopropane systems can bind to one Li+ ion; however, the corresponding the methylated systems can bind with two Li+ ions. The cyclopropane systems can adsorb six hydrogen molecules with an average binding energy of 3.8 kcal/mol. The binding free energy (ΔG) values suggest that the hydrogen adsorption process is feasible at 273.15 K. The calculation of desorption energies indicates the recyclable property of gas adsorbed complexes. The same number of CO2 and CO gas molecules can also be adsorbed with an average binding energy of -14.4 kcal/mol and -10.7 kcal/mol, respectively. The carbon dioxide showed ~3-4 kcal/mol better binding energy as compared to carbon monoxide and hence such designed systems can function as a potential candidate for the separation of these flue gas molecules. The nature of interactions in complexes was examined with atoms in molecules analysis revealed the electrostatic nature for the interaction of Li+ ion with cyclopropane rings. The chemical hardness and electrophilicity calculations showed that the gas adsorbed complexes are rigid and therefore robust as gas storage materials.

Estimation of adsorption capacity of CO2, CH4, and their binary mixtures in Quidam shale using LSSVM: Application in CO2 enhanced shale gas recovery and CO2 storage

Carbon dioxide enhanced shale gas recovery depends strongly on adsorption properties of carbon dioxide and methane. In this work, Least Squares Support Vector Machine (LSSVM) optimized by Particle Swarm Optimization, has been proposed to learn and then predict adsorption capacity of methane and carbon dioxide from pure and binary gas mixtures in Jurassic shale samples from the Qaidam Basin in China based on input parameters pressure, temperature, gas composition and TOC. A literature dataset of 348 points was applied to train and validate the model. The predicted values were compared with the experimental data by statistical and graphical approaches. The coefficients of determination of carbon dioxide adsorption were calculated to 0.9990 and 0.9982 for training and validation datasets, respectively. For CH4 the numbers are 0.9980 and 0.9966. The model was extrapolating reasonable trends beyond measurement ranges. More extensive datasets are needed to properly parameterize the role of shale properties.

Poly(ionic liquid)-Modified Metal Organic Framework for Carbon Dioxide Adsorption.

The design and synthesis of solid sorbents for effective carbon dioxide adsorption are essential for practical applications regarding carbon emissions. Herein, we report the synthesis of composite materials consisting of amine-functionalized imidazolium-type poly(ionic liquid) (PIL) and metal organic frameworks (MOFs) through complexation of amino groups and metal ions. The carbon dioxide adsorption behavior of the synthesized composite materials was evaluated using the temperature-programmed desorption (TPD) technique. Benefiting from the large surface area of metal organic frameworks and high carbon dioxide diffusivity in ionic liquid moieties, the carbon dioxide adsorption capacity of the synthesized composite material reached 19.5 cm3·g−1, which is much higher than that of pristine metal organic frameworks (3.1 cm3·g−1) under carbon dioxide partial pressure of 0.2 bar at 25 °C. The results demonstrate that the combination of functionalized poly(ionic liquid) with metal organic frameworks can be a promising solid sorbent for carbon dioxide adsorption.

A Universal Machine Learning Algorithm for Large-Scale Screening of Materials.

Application of machine learning (ML) methods for the determination of the gas adsorption capacities of nanomaterials, such as metal-organic frameworks (MOF), has been extensively investigated over the past few years as a computationally efficient alternative to time-consuming and computationally demanding molecular simulations. Depending on the thermodynamic conditions and the adsorbed gas, ML has been found to provide very accurate results. In this work, we go one step further and we introduce chemical intuition in our descriptors by using the "type" of the atoms in the structure, instead of the previously used building blocks, to account for the chemical character of the MOF. ML predictions for the methane and carbon dioxide adsorption capacities of several tens of thousands of hypothetical MOFs are evaluated at various thermodynamic conditions using the random forest algorithm. For all cases examined, the use of atom types instead of building blocks leads to significantly more accurate predictions, while the number of MOFs needed for the training of the ML algorithm in order to achieve a specified accuracy can be reduced by an order of magnitude. More importantly, since practically there are an unlimited number of building blocks that materials can be made of but a limited number of atom types, the proposed approach is more general and can be considered as universal. The universality and transferability was proved by predicting the adsorption properties of a completely different family of materials after the training of the ML algorithm in MOFs.