AUTHOR=Niu Yanhui , Yu Wenbin , Yang Shuguang , Wan Quan 

TITLE=Pyrolytic Behavior of Long-Chain Alkyl Quaternary Ammonium Bromide Inside Nanopores

JOURNAL=Frontiers in Energy Research

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2021.799237

DOI=10.3389/fenrg.2021.799237

ISSN=2296-598X

ABSTRACT=<p>The pyrolytic behavior of organic matter inside nanopores was studied by simultaneous thermogravimetric/differential scanning calorimetry analyzer coupled with Fourier transform infrared spectroscopy (STA/TG-FTIR). Nanoporous silica was prepared by a hydrothermal method using long-chain alkyl quaternary ammonium bromide (C<sub>n</sub>TAB, <italic>n</italic> = 12, 14) as a template. The pyrolytic behavior of C<sub>n</sub>TAB inside nanopores with different diameters was investigated and compared with that of C<sub>n</sub>TAB inside and outside nanopores. The results showed that the pyrolytic removal process consisted of the following features: 1) C<sub>n</sub>TAB underwent carbon chain decomposition and oxidation; 2) the DSC exothermal peak of C<sub>n</sub>TAB came mainly from its oxidative combustion, and the oxidative combustion temperature decreased with increasing pore size; 3) the C<sub>n</sub>TAB inside nanopores underwent crystallization–amorphous state phase transition, and C<sub>n</sub>TAB got trapped inside the calcined nanopores. In addition, the pyrolytic behavior of C<sub>n</sub>TAB inside the calcined nanopores was found to be similar to that of the uncalcined nanopores. This study aims to understand the storage and transformation processes of organic hydrocarbons under nanopore-confinement effect.</p>