Nitric Oxide (NO) separation from flue gas by chemical modified mesoporous silica

Three kinds of chemically modified silica were prepared to adsorb NO by surface modifying with vinyltriethoxysilane, acrylic acid and acryl amide respectively, and characterized by N 2 adsorption experiments, Fourier transform infrared spectroscopy, scanning electron microscopy and thermo-gravity analysis. The results showed that COOH and CONH 2 in the monomers had been grafted on the silica surface, and the pore volumes of S 1 , S 2 and S 3 decreased and exhibited the mesoporous structure; all the modified adsorbents could maintain steady under 300 °C. NO adsorption experiments were also carried out and the results suggested that the silica modified with acryl amide had the best NO adsorption capacity due to the relative large surface area and the stronger hydrogen bonds between NO molecules and the functional groups. The adsorbed NO molecules could be well desorbed by purging with N 2 so that the adsorbents could be recycled and NO resource also had the chance to be reused.