CO2 capture by amino-functionalized graphene oxide

Human activity is increasing CO2 atmospheric concentration contributing to global warming. In this situation CO2 reversible capture and storage, what it is known as carbon capture and conversion (CCC), can be part of the solution. In this context, searching for a suitable material for this application is necessary. The present study was carried out to investigate the CO2adsorption of amino-functionalized graphene oxide on its surface. Amino-functionalized graphene oxide samples were prepared by different methods with two kind of molecules: 3-aminopropyltrimethoxysilane (APTMS) and polyethylenimine (PEI). A characterization study of the prepared samples was done with thermal analysis, thermogravimetry (TG) and differential scanning calorimetry (DSC), and X-ray photoelectron spectroscopy (XPS). To evaluate the CO2adsorption of the samples CO2 adsorption isotherms were done. These isotherms correspond with a type I and shows an improvement in CO2 chemisorption regarding graphene oxide.This work was supported by “Help Industrial Doctorate” granted by the University of Cantabria in its 2014 call associated with the project Nº 51.DI03.648 and it is gratefully acknowledged

Highly hydrophobic organic coatings based on organopolysilazanes and silica nanoparticles: evaluation of environmental degradation

Hydrophobic coatings have potential applications in various fields, including for corrosion and weathering protection. In this study, we investigated the use of organopolysilazanes (OPSZs) combined with hydrophobic nanoparticles (NPs) on steel as a substrate to obtain hydrophobic coatings. The coatings were characterized using various techniques, and their hydrophobic properties and corrosion and weathering resistance were evaluated under near-shore marine conditions with high salinity, humidity and UV radiation. Our results show that the coatings exhibited excellent hydrophobic properties and significantly improved corrosion and weathering resistance compared to an uncoated steel and a pristine polymer. These findings suggest that the developed coatings have the potential to provide protection against corrosion for atmospheric and splash exposures in marine environments.This research was funded by the Ministry of Science, Innovation and Universities of Spain, through the Torres Quevedo Program, grant number PTQ2018-009743

CO2 capture at low temperature by nanoporous silica modified with amine groups

MCM-41 and SBA-15 were chosen as nanoporous materials based on silica for its modification with aminegroups. This modification was done by two methods: grafting method and wet impregnation method. The firstmethod grafted-amine groups by chemical reaction between surface silanol groups in the nanoporousmaterials and 3-aminopropyltrimetoxilane (APTMS).In the wet impregnation method, low molecular weightpolyethylenimine (PEI) is incorporated trough this method. These modified materials capture CO2 at lowtemperature. CO2 capture on the sorption sites by amine loading is believed to occur via chemisorptionmechanism by formation of ammonium carbamate. The evaluation and analysis of CO2 adsorption was carriedout by two methods: static mode and dynamic mode. The static mode is a pure CO2 adsorption-desorptionisotherms at 298K. The isotherms of the functionalized materials show a behavior by chemisorption, captureat low pressure, being the desorption branch almost horizontal, while nanoporous silica isotherms is due aphysical adsorption, low CO2 capture at low pressure and dependence with pressure, a complete reversibilityof the desorption process. The dynamic mode is a thermogravimetry study at different N2/CO2 concentrations.Isothermal CO2 captures at 298K were carried out to evaluate the suitability of the samples for cyclicoperation. The mass increase during the capture step was interpreted as CO2 adsorption capacity of thesamples. The results obtained by both methods were compared, and, its differences were analyzed