The concurrent utilization of an adsorbent and absorbent for carbon dioxide (CO2) adsorption with synergistic effects presents a promising technique for CO2 capture. Here, 1-butyl-3-methylimidazole acetate ([Bmim][Ac]), with a high affinity for CO2, and the molecular sieve SAPO-34 were selected. The impregnation method was used to composite the hybrid samples of [Bmim][Ac]/SAPO-34, and the pore structure and surface property of prepared samples were characterized. The quantity and kinetics of the sorbed CO2 for loaded samples were measured using thermogravimetric analysis. The study revealed that SAPO-34 could retain its pristine structure after [Bmim][Ac] loading. The CO2 uptake of the loaded sample was 1.879 mmol g-1 at 303 K and 1 bar, exhibiting a 20.6% rise compared to that of the pristine SAPO-34 recording 1.558 mmol g-1. The CO2 uptake kinetics of the loaded samples were also accelerated, and the apparent mass transfer resistance for CO2 sorption was significantly reduced by 11.2% compared with that of the pure [Bmim][Ac]. The differential scanning calorimetry method revealed that the loaded sample had a lower CO2 desorption heat than that of the pure [Bmim][Ac], and the CO2 desorption heat of the loaded samples was between 30.6 and 40.8 kJ mol-1. The samples exhibited good cyclic stability. This material displays great potential for CO2 capture applications, facilitating the reduction of greenhouse gas emissions.

Efficient CO2/CH4 separation for biogas upgrading can be achieved by using ionic liquids (ILs) as absorbents. In this study, a novel index named “relative absorption ability” (RAA) was proposed for the first time to facilitate the screening and evaluation of potential absorbents based on their thermodynamic and kinetic properties for CO2/CH4 separation. Subsequently, the properties of 2009 ILs were predicted with the conductor-like screening model, and the top 10 ILs were screened. Finally, the cost of the screened top two ILs for CO2/CH4 separation was further estimated with process simulation. The results further prove the reliability of the new proposed RAA index in screening and evaluating, and the screened promising ILs can reduce the costs of CO2/CH4 separation by 53.9% and 51.9%, respectively, in comparison to the current commercial technology.

A series of TiO2 nanotube arrays (TNAs) with different diameters and roughness were prepared by electrochemical anodization method by changing the fluoride ion concentration [0.4%, 0.3%, 0.2%(mass)] and applied voltage(15, 25, 35, 45 V). The scanning electron microscopy (FESEM) and atomic force microscopy (AFM) results showed that the wall thickness of the prepared TNAs increased and the roughness decreased with the decrease of fluoride ion concentration in the electrolyte. The effects of surface roughness and diameter on the surface mechanical properties of TNAs and the interaction of Cytochrome C (Cyt C) were studied by AFM characterization. The results show that the adhesion is proportional to the contact area. With the increase of the diameter of the TNAs, the wall thickness decreases, the effective contact area between TNAs and Cyt C increases first and then decreases, and the forces of Cyt C with TNAs also increase first and then decrease. The roughness decreases when the diameter was fixed, the effective area of TNAs increases, and the interaction force also increases. It can be seen that the surface roughness and effective contact area of TNAs can be effectively controlled by changing the fluoride ion concentration of the electrolyte, which is further beneficial to promoting interaction with protein molecules.

CO2 capture and separation (CCS) is a key step to mitigate greenhouse gas emissions and develop renewable energy. The trade-off between the rate and efficiency in the CO2 separation process cannot be solved with the traditional process intensification. Using nano-interface to realize process intensification has been widely used in the chemical process with multi-phase transfer, and CO2 separation is one of examples. This review summarizes the research work from the establishment of CO2 transfer model at nano-interface and the resistance regulation, the acquisition of the CO2 chemical potentials at equilibrium and at the nano-interface (the driving force regulation) and the molecular simulation analysis of the interface enhancement mechanism. Based on the theoretical studies, the resistance distribution for the CO2 separation process in a real absorption tower is further analyzed and a "three-stage strengthening scheme" is proposed to decrease the investment and operating costs. © All Right Reserved.

Agitation power consumption (P) in the anaerobic digestion of biogas plants is a major part of the electric energy consumption. To reduce P by adjusting the rheological properties, in this work, the rheological properties of corn straw slurry were studied systematically with the consideration of the effects of TS, temperature and particle sizes. The P was calculated based on the rheological behaviour of corn straw slurry. The investigation shows that the thermophilic digestion is effective only for the slurry with a relatively high TS. The size-reduction is more effective at higher TS compared to the option of increasing temperature in order to improve the agitation power efficiency, and the value of P can be reduced by up to 48.11 %. Since the size-reduction can also increase the methane yield, the adjustment of particle sizes is a promising option to save P, especially at higher TS.

Interfacial transfer at mesoscale is a common issue for all the multi-phase chemical processes, and the related study remains as a scientific challenge due to the complexities. Investigating the interfacial interactions at mesoscale to find out the regulation strategies is the key to realize process-intensification of mass-transfer and reaction for the advanced chemical industries. To accurately describe the behavior of fluids at the interface, a new molecular thermodynamic model that can describe the complex fluid-solid interface interaction. When the molecular thermodynamic modeling method is extended to the nano-micro interfacial transfer needs to be developed, calling for the coordination of advanced experiments at nano-micro scale and molecular with molocular thermodynamic modelling. Atomic force microscopy (AFM), which possess the sensitivity down to nanoscale, can directly obtain the interfacial interaction at nano-micro scale. The quantification of AFM-measured forces can be used to construct the coarse-grained molecular model and describe complex interfacial interaction. Then, the coarse-grained molecular model can reveal the molecular thermodynamic mechanism of nano- and micro- interface transfer, realizing quantitative prediction.

The nanoparticles generally show abnormal properties compared to those in the bulk phase, and they exhibit significant potential in various applications such as catalysis and energy conversion. However, the theoretical work for describing the properties of nanoparticles is limited with poor prediction capacity. In this work, the Gibbs free energy was studied, from both macroscope and microscope, predictive models were proposed to study the thermodynamic properties of nanoparticles with a generalized description of the Gibbs free energy considering the effects of surface-energy and the substrate contacted. The proposed model from the microscope was based on the corresponding states theory to describe the effect of the substrate on the Gibbs free energy of nanoparticles, in which the molecular parameter with a generalized constant was obtained from the melting point of metals due to sufficient experimental information. The comparison with the new measured experimental results proves the reliability of the model prediction