Advanced dual-artificial neural network system for biomass combustion analysis and emission minimization.

Management of agricultural waste is an important part of plantation operations. Not all wastes are suitable for composting or the process is simply inefficient and time-consuming. In their case, thermal treatment is acceptable, but it is necessary to optimize the process to minimize greenhouse gas emissions.

Artificial neural networks to differentiate the composition and pyrolysis kinetics of fresh and long-stored maize.

In this study, a novel methodology to determine plant biomass composition using artificial neural networks (ANN) is presented. This study was performed to determine the changes in the composition of fresh and 12 month-long stored biomass samples. The production of biofuels is a common method used to manage agricultural waste.

Analyzing the kinetics of waste plant biomass pyrolysis via thermogravimetry modeling and semi-statistical methods.

This article presents a methodology for determining the kinetic parameters of biomass based on thermogravimetric analysis and the Coats-Redfern procedure with 27 model equations. Maize samples stored for approximately one year were used herein. The first sub-stage of pyrolysis was a first-order reaction with nuclei growth of n = 1, and the second sub-stage indicated a different kinetic order (1.

The pump-mixed anaerobic digestion of pig slurry: new technology and mathematical modeling.

Biogas production is a relatively novel and developing branch of the renewable fuel sector, which allows agricultural waste, and more, to be used as a feedstock. New technologies have been integrated into the process to improve its efficiency. In this study, a pump-mixed anaerobic digestion concept is considered for both experimental and modeling approaches.

Innovations in anaerobic digestion: a model-based study.

Background: Increasing the efficiency of the biogas production process is possible by modifying the technological installations of the biogas plant. In this study, specific solutions based on a mathematical model that lead to favorable results were proposed. Three configurations were considered: classical anaerobic digestion (AD) and its two modifications, two-phase AD (TPAD) and autogenerative high-pressure digestion (AHPD).

A DFT Study of CO Hydrogenation on Faujasite-Supported Ir Clusters: on the Role of Water for Selectivity Control.

Reaction mechanisms for the catalytic hydrogenation of CO by faujasite-supported Ir clusters were studied by periodic DFT calculations. The reaction can proceed through two alternative paths. The thermodynamically favoured path results in the reduction of CO to CO, whereas the other, kinetically preferred channel involves CO hydrogenation to formic acid under water-free conditions.

The role of Ir4 cluster in enhancing the adsorption of CO2 on selected zeolites - GCMC simulations.

We have investigated the adsorption of CO2 molecules inside the EMT, SAO, SBS, SBT and IWS zeolites with respect to the influence of the Ir4 clusters on the adsorption capabilities of these materials. We have determined that the capabilities of CO2 adsorption depend on the combined effect of the framework topology and the position of the Ir4 cluster. Adsorption intensifies despite the fact that a fraction of the pore volume is occupied by the Ir4 cluster, and thus, the adsorption is more intense than that on empty zeolite.

GCMC simulations of CO2 adsorption on zeolite-supported Ir4 clusters.

We have studied the adsorption of CO2 molecules inside the pores of faujasite zeolite and evaluated the influence of the Ir4 clusters on the intensity of the adsorption. The force field designed for CO2 adsorption in zeolites has been extended with the parameters for the CO2/Ir4 interactions, taking the Density Functional Theory (DFT) energies as a reference. We have found that despite the fraction of the pore volume that is occupied by the Ir4 cluster, the adsorption is more intense than that of empty faujasite.

DFT modeling of CO2 adsorption on Cu, Zn, Ni, Pd/DOH zeolite.

This study is the analysis of the adsorption process of the CO2 molecule on the cationic sites of the DOH zeolite. Based on the DFT method, we have been able to identify several adsorption sites containing extra-framework cations and evaluate the value of the adsorption energy with respect to the distance from the adsorption site. The zinc cation has been found to cause the strongest interaction with the CO2 molecule.

Adsorption equilibria of hydrocarbons in the structure of the reforming catalyst: molecular modeling.

Molecular modeling was used to analyze the phenomena involved in the sorption of hydrocarbons by the Pt/Al2O3 reforming catalyst. The interactions between the atoms of the catalyst structure and the molecules of the model reforming compounds were described in terms of the universal forcefield. Making use of the GCMC algorithms, the adsorption isotherms for the reagents in the catalytic system and the temperature dependence of the Henry constant were determined.

Effect of Pt and Sn on the adsorption of n-heptane in gamma-Al2O3 catalyst models.

The Grand Canonical Monte-Carlo (GCMC) method has been used to carry out simulations of the adsorption of n-heptane in models of naphtha-reforming catalysts. Models used in the study differed in the number and distribution of metal atoms-Pt and Sn. The number of adsorbed n-heptane molecules grows linearly with increasing number of metal atoms.

Simulating adsorption of n-heptane in the Pt/Al2O3 model: influence of platinum.

The molecular modeling method refered to in the literature as Grand Canonical Monte Carlo was used to analyze the phenomenon of n-heptane adsorption on the Pt/gamma-Al(2)O(3) catalyst. In order to describe relevant interactions, use was made of the forcefield methods (UFF and CVFF). With the conditions adopted for the purpose of the study, Pt was found to exert an advantageous effect on the adsorption of n-heptane.

Diffusion of hydrocarbons in the reforming catalyst: molecular modelling.

This is an analysis of the diffusion and adsorption of the model reagents involved in the reforming process (heptane, methylcyclohexane and toluene) in the support (gamma-Al2O3) and catalyst (Pt/gamma-Al2O3) made use of in this process. Since the properties of these catalytic systems are influenced by the interactions between the atoms of the catalyst structure (host) and the atoms of the reagents (guest), analysis was carried out at the molecular level, using advanced computer simulations (molecular dynamics and forced diffusion) implemented in the MSI Software. The virtual host-guest model constructed with this software enabled a simulation of the real reforming system (reforming catalyst-reagents) and analysis of the diffusion phenomenon in this system.