Multiscale analysis of CO adsorption mechanisms on porous carbon: An investigation into the impact of intrinsic defects and pore size.

Porous carbon adsorption represents a critical component of CCUS technologies, with microporous structures playing an essential role in CO capture. The preparation of porous carbon introduces intrinsic defects, making it essential to consider both pore size and these defects for a comprehensive understanding of the CO adsorption mechanism. This study investigates the mechanisms of CO adsorption influenced by intrinsic defects and pore size using multiscale methods, incorporating experimental validation, Grand Canonical Monte Carlo simulations, and Density Functional Theory simulations.

Quantitative simulationSimulation of nitrogen doping effects on benzene selective adsorption by activated carbon in aqueous conditions.

Investigating the impact of nitrogen doping on the selective adsorption of benzene on activated carbon under aqueous conditions holds significant importance in regulating nitrogen content on activated carbon precisely and enhancing benzene adsorption in the air. This study utilizes quantum chemical simulation to systematically compute the pairwise interactions of pyridine nitrogen, pyrrole nitrogen, graphite nitrogen, and their coexistence on carbon materials, including electrostatic potential, van der Waals potential, and polarity changes. We examine the adsorption of benzene and water on nitrogen-doped carbon materials and calculate the type and proportion of weak interactions in the adsorption process through energy decomposition analysis.

Degradation of phenol by metal-free electro-fenton using a carbonyl-modified activated carbon cathode: Promoting simultaneous HO generation and activation.

The low yield of hydrogen peroxide, narrow pH application range, and secondary pollution due to iron sludge precipitation are the major drawbacks of the electro-Fenton (EF) process. Metal-free electro-Fenton technology based on carbonaceous materials is a promising green pollutant degradation technology. Activated carbon cathodes enriched with carbonyl functional groups were prepared using a two-step annealing method for the degradation of phenol pollutants.

Optimization Strategy for Formaldehyde Removal by Carbon Cathode Electro-Fenton: Enhancement of Formaldehyde and Oxygen Co-adsorption by Rational Nitrogen Doping Types.

This study investigates the effect of N-doped coal-based activated carbon cathode on formaldehyde-oxygen coadsorption. Further investigation investigates the effect of formaldehyde-oxygen coadsorption on HO generation and formaldehyde removal in an electro-Fenton system. Nitrogen doping enhances formaldehyde and oxygen coadsorption by modulating competitive adsorption.

The promotion mechanism of different nitrogen doping types on the catalytic activity of activated carbon electro-Fenton cathode: Simultaneous promotion of HO generation and phenol degradation ability.

Doping with nitrogen atoms can improve the catalytic activity of activated carbon cathodes in electro-Fenton systems, but currently there is a lack of understanding of the catalytic mechanism, which limits the further development of high-performance activated carbon cathodes. Here, a multi-scale exploration was conducted using density functional theory and experimental methods to investigate the mechanism of different nitrogen doping types promoting the redox performance of activated carbon cathodes and the degradation of phenol. The density functional theory results indicate that the introduction of nitrogen atoms enhances the binding ability between carbon substrates and oxygen-containing substances, promotes the localization of surrounding electrons, and makes it easier for O to bind with protons and catalyze the hydrogenation reaction of *OOH.

Mechanisms of efficient indoor formaldehyde removal via electro-Fenton: Synergy in ·OH generation and utilization through a modified carbon cathode.

Indoor formaldehyde poses a significant carcinogenic risk to human health, making its removal imperative. Electro-Fenton degradation has emerged as a promising technology for addressing this concern. In the electro-Fenton system, ·OH is identified as the primary active species responsible for formaldehyde removal.

A new strategy for improving the energy efficiency of electro-Fenton: Using N-doped activated carbon cathode with strong Fe(III) adsorption capacity to promote Fe(II) regeneration.

Fe(II) regeneration plays a crucial role in the electro-Fenton process, significantly influencing the rate of ·OH formation. In this study, a method is proposed to improve Fe(II) regeneration through N-doping aimed at enhancing the adsorption capacity of the activated carbon cathode for Fe(III). N-doping not only enriched the pore structure on the surface of activated carbon, providing numerous adsorption sites, but also significantly increased the adsorption energy for Fe(III).

Effect of different defects on the competitive adsorption of formaldehyde and water on the surface of carbon materials: Density functional theory study.

The adsorption of formaldehyde by carbon materials is extremely limited and is also greatly influenced by the competitive adsorption of water. Therefore, it is of great significance to investigate the effect of different defects on the competitive adsorption of formaldehyde and water on the surface of carbon materials, and consequently the targeted modification of carbon materials to promote the adsorption of formaldehyde in air. In this study, multi-scale simulations were conducted to explore the problem of competitive adsorption of water and formaldehyde on the surface of carbon materials by quantum chemistry and molecular dynamics.

Investigation of the Mechanisms of CO/O Adsorption Selectivity on Carbon Materials Enhanced by Oxygen Functional Groups.

Power plant flue gas and industrial waste gas are produced in large quantities. Using these as feedstocks for CO electroreduction has important practical significance for the treatment of excessive CO emissions. However, O in such sources strongly inhibits the electrochemical conversion of CO.

Strategies for promoting the degradation of phenol by electro-Fenton: Simultaneously promoting the generation and utilization of HO.

The use of the electro-Fenton process to continuously generate HO and efficiently degrade organic pollutants is considered a promising technology. The ratio of generation of HO is usually regarded as the critical step; however, how the HO is utilized is also of particular importance. Herein, activated carbon was activated at different temperatures and used to explore the effect of nitrogen doping on the production and utilization of HO in the electro-Fenton-based degradation of organic pollutants.

Synergistic mechanism of formaldehyde adsorption by intrinsic defects and carboxyl groups on the surface of carbon materials.

The adsorption of formaldehyde on the original carbon material is limited. Determining the synergistic adsorption of formaldehyde by different defects on the carbon material is necessary for comprehensively understanding the mechanism of formaldehyde adsorption on the surface of the carbon material. The synergistic effect of intrinsic defects and oxygen-containing functional groups on formaldehyde adsorption on the surface of carbon materials was simulated and verified by experiments.

Quantitative analysis on the oil content of oilfield wastewater based on a convolutional neural network model and ultraviolet transmission spectroscopy.

Oil content (OC) is one of the important evaluation indicators in oilfield wastewater (OW) treatment. The purpose of this study is to realize online real-time detection of OC in OW by combining ultraviolet spectrophotometry with the convolutional neural network (CNN). In this paper, 80 groups of OW transmission data were measured for model establishment.

Effect of oxygen functional groups on competitive adsorption of benzene and water on carbon materials: Density functional theory study.

It is important to study the effect of oxygen-containing functional groups on the competitive adsorption mechanism of benzene and water on the surface of carbon materials, and to directional modification of activated carbon to improve its selective adsorption of benzene in air. In this study, the adsorption characteristics of benzene and water on original and linked ester, carboxyl, hydroxyl, carbon materials linked by ether groups were calculated by quantum chemical simulation based on density functional theory. The types and proportions of weak interactions in the adsorption process were calculated by energy decomposition analysis, and the adsorption mechanism of carbon materials for water and benzene was described.

Promotion of formaldehyde degradation by electro-Fenton: Controlling the distribution of ·OH and formaldehyde near cathode to increase the reaction probability.

The mismatch of pollutant concentration and ·OH concentration is the key reason for the inefficient degradation of formaldehyde in the electro-Fenton system. Therefore, formaldehyde and ·OH are adsorbed near the cathode, and the high concentration reaction region is constructed to increase the reaction probability, which is called control of the reaction region. Through nitrogen doping modification of the activated carbon cathode, the adsorption capacity of the modified cathode for formaldehyde and active species, and the selectivity of the two-electron oxygen reduction reaction were deeply analyzed.

DPD simulations on mixed polymeric DOX-loaded micelles assembled from PCL-SS-PPEGMA/PDEA-PPEGMA and their dual pH/reduction-responsive release.

The design of mixed polymeric micelles by a combination of two or more dissimilar polymers is a potential strategy to achieve multiple stimuli-response for anti-cancer drug delivery. However, their drug loading co-micellization behavior and multiple stimuli-responsive drug release mechanism have been poorly understood at the mesoscopic level, especially in the system that involves reduction-response due to the difficulty of simulation on the cleavage of chemical bonds. In this work, the co-micellization behavior, drug distribution regularities and dual pH/reduction-responsive drug release process of mixed micelles formed by disulfide-linked polycaprolactone-b-polyethylene glycol methyl ether methacrylate (PCL-SS-PPEGMA) and poly(ethylene glycol) methyl ether-b-poly(N,N-diethylamino ethyl methacrylate) (PDEA-PPEGMA) were studied by dissipative particle dynamics (DPD) mesoscopic simulations.

Cost-effective method of benzene-containing wastewater treatment using floating electro-Fenton system.

Traditional electro-Fenton systems must continuously supply oxygen to the cathode, which leads to extensive volatilisation of benzene in solutions. In this study, we adopted a floating cathode electro-Fenton system without bubbling oxygen into the solution to treat benzene-containing wastewater. The effects of the floating cathode position and main reaction parameters on benzene degradation were analysed, and the degradation cost was estimated.

Numerical study for removing wax deposition by thermal washing for the waxy crude oil gathering pipeline.

Exploring the wax removal process by numerical simulation is beneficial for guiding field operations. In this paper, enthalpy-porosity and volume of fluid (VOF) methods were adopted to simulate the melting process of wax in the crude oil gathering pipeline. The melting patterns and liquid fraction of the wax were used to validate the mathematical model.

Roles of free radicals in NO oxidation by Fenton system and the enhancement on NO oxidation and HO utilization efficiency.

Low HO utilization efficiency is the main problem when Fenton system was used to oxidize NO in flue gas. To understand the behaviour of the free radicals during NO oxidation process in Fenton system is crucial to solving this problem. The oxidation capacity of [Formula: see text] and [Formula: see text] on NO in Fenton system was compared and the useless consumption path of [Formula: see text] and [Formula: see text] that caused the low utilization efficiency of HO were studied.

Optimization of NO oxidation by H2O2 thermal decomposition at moderate temperatures.

H2O2 was adopted to oxidize NO in simulated flue gas at 100-500°C. The effects of the H2O2 evaporation conditions, gas temperature, initial NO concentration, H2O2 concentration, and H2O2:NO molar ratio on the oxidation efficiency of NO were investigated. The reason for the narrow NO oxidation temperature range near 500°C was determined.

Free radical behaviours during methylene blue degradation in the Fe/HO system.

Behaviours of the free radicals during the methylene blue (MB) oxidation process in the Fe/HO system were studied to reveal the reason for the low utilization efficiency of HO. The roles of , and radicals were proven to be different in the MB oxidation process. The results showed that radicals had a strong ability to oxidize MB; however, they were not the main active substances for MB degradation due to the low concentration in the traditional Fe/HO system.

The role of quinone cycle in Fe-HO system in the regeneration of Fe.

The reaction between Fe and HO generates highly reactive ·OH. However, the weak conversion from Fe to Fe limits its continuous reaction. Here, the difference between the Fenton system and modified Fenton system for the regeneration of Fe was analyzed.