Article
Thermodynamics
Ze-Kai Gu, Chuan-Yong Zhu, Zhao-Qin Huang, Ming-Hai Xu, Liang Gong
Summary: The study found that functional groups on the surface of activated carbon increase the adsorption heat and capacity of aromatics at low pressures, while an increase in density decreases the saturation adsorption capacity and pressure. The molecular diameter and mesopore size of aromatics also significantly affect adsorption behavior.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Engineering, Environmental
Ana Luisa Galdino, Jose C. A. Oliveira, Madson L. Magalhaes, Sebastiao M. P. Lucena
Summary: A molecular simulation approach was used to understand the relationship between pore size and adsorption capacity in activated carbons for phenolic compounds removal. The results showed that the pore size of 8.9 angstrom was the most efficient, and a predictive model based on the representative pore methodology was proposed and validated. The method was also demonstrated to be extendable to other phenolic compounds.
WATER SCIENCE AND TECHNOLOGY
(2021)
Article
Environmental Sciences
Jose Carlos Alexandre de Oliveira, Paulo Ricardo Moura Rodrigues, Sebastiao Mardonio Pereira de Lucena
Summary: This study utilized molecular simulation and the representative pores method to predict the adsorption of phenol and related compounds on activated carbon with different pore sizes. The results showed the most effective pore sizes for adsorption and provided a predictive model for carbon selection and synthesis.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Biochemical Research Methods
Zihan Chen, Ren He
Summary: This study investigates the adsorption competition characteristics between multi-component gases at different pressures by using molecular simulation method. The results show that the selectivity of activated carbon to toluene is negatively correlated with the adsorption pressure, while the opposite is true for ethanol. The competitive order of the three VOCs is toluene > cyclohexane > ethanol at low pressure, which becomes ethanol > toluene > cyclohexane at high pressure.
JOURNAL OF MOLECULAR GRAPHICS & MODELLING
(2023)
Article
Environmental Sciences
Xiaolong Yao, Jingya Zhou, Zheng Liu
Summary: In this study, a starch-based activated carbon was prepared using carbonization activation, and it exhibited high adsorption capacity and performance for low-concentration methyl mercaptan. The well-developed microporous structure and surface functional groups played a crucial role in the adsorption of methyl mercaptan.
Article
Green & Sustainable Science & Technology
Zihan Chen, Ren He
Summary: This paper investigates the effects of pore size, functional groups, and water content on the adsorption performance of activated carbon for four gasoline evaporation volatile organic compounds (VOCs) through molecular simulation. The results show that capillary condensation increases the equilibrium adsorption capacity, while functional groups and water molecules reduce the effective adsorption volume. The threshold pressure depends on interaction energy and the number of adsorption sites, with the lowest threshold pressure observed for all VOCs. The presence of functional groups and water molecules increases the threshold pressure for n-butane, n-hexane, and p-xylene, while functional group modification and a certain amount of water molecules enhance the adsorption capacity of ethanol at low pressure.
ENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY
(2023)
Article
Materials Science, Multidisciplinary
Changwu Zou, Yu Li, Yini Du, Yang Huang, Yue Wu, Ting Zhao, Lingxuan Zhang, Xuemei Luo
Summary: This study investigated the adsorption behavior of water molecules on lignite-based activated carbon. It was found that the introduction of hydroxyl functional groups significantly increased the adsorption capacity, while the pore size distribution had a minor effect on the adsorption amount. However, at higher oxidation levels, the pore size distribution significantly limited the size of water clusters.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2022)
Article
Chemistry, Physical
Jose C. A. Oliveira, Daniel V. Goncalves, Pedro F. G. Silvino, Sebastiao Mardonio Pereira de Lucena
Summary: We compared the pore size distribution (PSD) obtained from CO2 adsorption isotherms on homogeneous and heterogeneous slit activated carbon models. The reactive molecular dynamics model (rMD) showed better fitting to the experimental isotherm and predicted a higher volume of ultramicropores in all activated carbons. Both PSD models accurately predicted light hydrocarbon isotherms, with rMD being more accurate. The study also revealed the limitations of implicit heterogeneous DFT-based models due to differences between AA and UA CO2 models in rMD heterogeneous ultramicropores.
ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY
(2023)
Article
Polymer Science
Ri-si Wang, Ya Li, Xi-xiang Shuai, Rui-hong Liang, Jun Chen, Cheng-mei Liu
Summary: Pectin/activated carbon microspheres (P/ACs) were prepared through simple gelation and showed good adsorption capacity for Pb2+, making them a potential candidate for heavy metal adsorbents. The adsorption process followed a pseudo-second-order model controlled by film diffusion, with maximum adsorption capacity estimated to be 279.33 mg/g. The mechanism of adsorption may involve ion exchange, electronic adsorption, complex formation, and physical adsorption.
Article
Chemistry, Multidisciplinary
Qi Zhang, Xiang C. Ma, Chang He, Qing L. Chen, Bing J. Zhang
Summary: Modification of raw activated carbon using chemical solvents, such as triethylenetetramine, can enhance its adsorption performance. Liquid impregnation experiments were conducted to investigate the adsorption of triethylenetetramine on activated carbon for modification. The Langmuir isotherm model and pseudo-first-order kinetic model fitted well with the experimental data, with R2 values of 0.9883 and 0.9954, respectively. The adsorption process was found to be spontaneous, endothermic, and monolayer physical adsorption.
Article
Environmental Sciences
Haitao Lin, Jianbo Lu, Azher M. Abed, Kaushik Nag, Mohamed Fayed, Ahmed Deifalla, Abdullah S. Bin Mahfouz, Ahmed M. Galal
Summary: This study presents a modeling and simulation of CO2 from natural gas using Pressure Swing Adsorption (PSA). PSA is a promising and cost-effective process for separating and capturing CO2 from industrial processes and power plants. The paper provides an overview of the PSA process, its application for CO2 capture, and discusses its advantages, limitations, and future research directions. The simulation solves the momentum, mass, and energy balance simultaneously, with four adsorption beds filled with activated carbon as adsorbent. The process involves two beds in adsorption conditions and the other two beds in desorption conditions, with desorption cycle including blow-down and purge steps. The linear driving force (LDF) and extended Langmuir isotherm are used for adsorption rate estimation and equilibrium between solid and gas phases respectively. The temperature changes through heat transfer and axial heat dispersion, and the set of partial differential equations is solved using implicit finite difference.
Article
Environmental Sciences
Ying Sheng, Mingyang Wang, Qingqing Dong
Summary: Adsorption is the most reliable technology for removing gaseous pollutants, and activated carbon is widely used as an adsorbent due to its good capacity and low cost. However, the presence of ultrafine particles (UFPs) can hinder the removal of gaseous pollutants and shorten the lifespan of activated carbon. This study used molecular simulation to investigate the adsorption of toluene on UFPs and analyzed the effects of UFPs' concentration, shape, size, and chemical composition on toluene adsorption.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Chemistry, Physical
S. M. P. Lucena, J. C. A. Oliveira, D. V. Goncalves, P. F. G. Silvino, S. Dantas, A. V. Neimark
Summary: A new kernel of heterogenous carbon surfaces was presented using the reactive molecular dynamics model, which explicitly incorporates edges and corrugations resulting from the oxidative etching of graphene walls. The model eliminates computational artifacts characteristic to homogeneous pore wall models. The rMD model performs similarly to the QSDFT model in reproducing carbon experimental isotherms, indicating it as a viable alternative for carbon characterization.
Article
Biochemistry & Molecular Biology
Yeray Alvarez-Galvan, Babak Minofar, Zdenek Futera, Marckens Francoeur, Corine Jean-Marius, Nicolas Brehm, Christelle Yacou, Ulises J. Jauregui-Haza, Sarra Gaspard
Summary: Adsorption is a successful method for removing heavy metal contaminants from water, and using residual biomass to produce adsorbents is an environmentally friendly approach. This study explored the transformation of Sargassum seaweed into activated carbon and characterized its properties. The adsorption capacity of the activated carbon was influenced by solution pH, temperature, contact time, and Cr(VI) concentration. Molecular dynamics simulations confirmed the experimental results and identified the influential functional groups in the adsorption process.
Article
Engineering, Environmental
Baogen Liu, Lingyun Yu, Huijun Wang, Xiancheng Ma, Zheng Zeng, Liqing Li
Summary: This study reveals the influence of oxygen doping on the surface heterogeneity and adsorption performance of volatile organic compounds (VOCs) through adsorption experiments and theoretical calculations. The results show that oxygen doping can significantly change the charge distribution on the carbon surface and enhance the adsorption capacity of methanol and acetone. The study also investigates the synergistic effect of oxygen-containing functional groups and finds no obvious synergistic effect.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Energy & Fuels
Somayeh Kolbadinejad, Hossein Mashhadimoslem, Ahad Ghaemi, Moises Bastos-Neto
Summary: In this study, artificial neural networks were utilized to accurately predict the adsorption amounts of different gases on zeolites and activated carbon, with Bayesian Regularization and Radial based functions algorithms showing high efficiency and accuracy.
CHEMICAL ENGINEERING AND PROCESSING-PROCESS INTENSIFICATION
(2022)
Article
Engineering, Chemical
Bianca Ferreira dos Santos, Juan Antonio Cecilia, Moises Bastos-Neto, Enrique Rodriguez-Castellon, Diana Cristina Silva de Azevedo, Enrique Vilarrasa-Garcia
Summary: Hollow microspheres of silica were synthesized with different ethanol/water ratios to investigate their morphology, porosity, and water adsorption capacity. Increasing ethanol/water ratio led to decreased pore volume and specific surface area, while the water adsorption capacity was similar to commercial adsorbents at high relative pressures but lower at low pressures. Regeneration of these samples required less energy, making them suitable for less demanding situations like coarse drying and water harvesting from air.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2022)
Article
Engineering, Chemical
Thalles S. Diogenes, Rafaelle G. Santiago, Debora A. S. Maia, Daniel V. Goncalves, Diana C. S. Azevedo, S. Mardonio P. Lucena, Moises Bastos-Neto
Summary: This study characterizes and investigates natural clinoptilolite through experimental and molecular simulation approaches. The obtained data can assist in the design of adsorption processes using clinoptilolite.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2022)
Article
Engineering, Chemical
Sebastiao M. P. de Lucena, Jose Carlos A. Oliveira, Daniel Goncalves, Lyssandra M. O. Lucas, Pedro A. S. Moura, Rafaelle G. Santiago, Diana C. S. Azevedo, Moises Bastos-Neto
Summary: Despite the industrial importance of zeolite LTA, there is still a lack of characterization methods based on adsorption for hindered diffusion of standard probe gases. In this study, the pore type distribution methodology was extended to zeolite materials for the first time. The methodology was applied to Na-LTA (4A) zeolite, and the individual contribution of supercages with different energy levels to total adsorption uptake was determined. The proposed methodology provides detailed and relevant information not obtained by existing methods and enables the use of adsorption for characterizing small pore sieves.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Bruno C. Amoni, Armando D. L. Freitas, Raquel A. Bessa, Cristiane P. Oliveira, Moises Bastos-Neto, Diana C. S. Azevedo, Sebastiao M. P. Lucena, Jose M. Sasaki, Jorge B. Soares, Sandra A. Soares, Adonay R. Loiola
Summary: An experimental investigation on the synthesis of zeolite A using treated fly ash showed that the treated fly ashes affected the synthesis yield and properties of the obtained zeolites, helping to decrease the viscosity of modified asphalt cement and improve its workability.
MATERIALS CHEMISTRY AND PHYSICS
(2022)
Article
Chemistry, Physical
Jose C. A. Oliveira, Daniel V. Goncalves, Pedro F. G. Silvino, Sebastiao Mardonio Pereira de Lucena
Summary: We compared the pore size distribution (PSD) obtained from CO2 adsorption isotherms on homogeneous and heterogeneous slit activated carbon models. The reactive molecular dynamics model (rMD) showed better fitting to the experimental isotherm and predicted a higher volume of ultramicropores in all activated carbons. Both PSD models accurately predicted light hydrocarbon isotherms, with rMD being more accurate. The study also revealed the limitations of implicit heterogeneous DFT-based models due to differences between AA and UA CO2 models in rMD heterogeneous ultramicropores.
ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY
(2023)
Article
Engineering, Chemical
Klaus F. S. Richard, Diana C. S. Azevedo, Moises Bastos-Neto
Summary: This paper investigates multiple machine learning methods for surrogate modeling and optimization of an experimentally validated pressure swing adsorption model, comparing their accuracy and precision with the commonly used artificial neural networks. It also explores ways to improve the model's accuracy using process knowledge, followed by the optimization of system parameters and quantification of computational time. All steps were successfully implemented using the open-source Python programming language, and the expected and unexpected results were discussed.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Physical
Daniel V. Goncalves, Danielle L. Montenegro, Jose C. A. Oliveira, Jhonny Villarroel-Rocha, Karim Sapag, Moises Bastos-Neto, Djalma R. da Silva, Sebastiao M. P. Lucena
Summary: We study the metastable phase α-alumina, β-alumina, and find that its pore shape is slit-like rather than cylindrical. Therefore, we propose a slit pore-based N-2 isotherm kernel method for characterizing the micropore range. The calculated results using this method show better agreement with experimental results compared to the method using cylindrical pores.
ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY
(2023)
Article
Chemistry, Physical
Jose C. A. Oliveira, Daniel V. Goncalves, Danielle L. Montenegro, Sebastiao M. P. Lucena
Summary: In this study, the prediction of hydrogen adsorption up to 700 bar using the Monte Carlo algorithm in the grand canonical ensemble and the representative pores method was proposed. The results showed a good agreement between the experimental and simulated data, and the maximum pressure where the highest adsorption of hydrogen occurs was determined.
ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY
(2023)
Article
Materials Science, Ceramics
Victor F. S. Alencar, Jose C. A. Oliveira, Andrea S. Pereira, Sebastiao M. P. Lucena
Summary: Molecular simulation and machine learning can be used to predict the modulus of elasticity of bioactive glasses and expand testing capacity. Sodium oxide and calcium oxide have the greatest impact on the modulus of elasticity, and glasses with 6% and 7% phosphorus pentoxide have higher modulus of elasticity and bioactivity. This study demonstrates the potential of molecular simulation and machine learning techniques in decision-making for glass synthesis with bioactivity.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2023)
Article
Chemistry, Physical
Jimmy D. L. Moreno, Daniele da S. Pereira, Thalita M. Azevedo, Darley C. de Melo, Debora A. S. Maia, Fateme Rezaei, Moises Bastos-Neto, Diana C. S. de Azevedo
Summary: This study investigates the protective effect of clay binder on the thermal fouling during zeolite adsorption drying process. The results show that the use of clay binder can effectively reduce the loss of adsorption performance in zeolite.
ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY
(2023)
Article
Chemistry, Applied
P. A. S. Moura, E. D. S. Ferracine, E. Rodriguez-Aguado, D. A. S. Maia, D. C. Melo, S. Valencia, D. Cardoso, F. Rey, M. Bastos-Neto, E. Rodriguez-Castellon, D. C. S. Azevedo
Summary: This study investigates the hydrothermal stability of cationic LTA zeolites and its impact on water adsorption and carbon deposition. The results show that the Si/Al ratio does not directly affect the crystallinity upon aging, but a high potassium content leads to amorphization. Aluminum migration from the outer surface to the inner cages occurs during aging. The presence of aluminum is correlated to carbon deposition. Acid sites in the zeolite enhance water adsorption but also lead to carbon accumulation. The sample with an intermediate Si/Al ratio and in Na-form exhibits excellent hydrothermal stability and high water affinity.