Glass capillaries with TiO2 supported on inner wall as microchannel reactors

Abstract

In this work, we have successfully immobilized TiO2 nanoparticles with small particle size and narrow size distribution on the inner surface of glass capillaries. By integrating the beneficial properties of nano-sized TiO2 particles with microreactors, the highly efficient catalytic system showed good performance in oxidation of dibenzothiophene (DBT) and photocatalytic discoloration of methyl orange (MO). The mean particle size and loading amount (Ti content: 0.21–2.81wt.%) are both controllable via the simple manufacturing procedure. The diameter varied from 6.8 to 20.8nm with the pH increased from 1.59 to 6.48 using ethanol as the solvent. Particles prepared by methanol showed the largest size (18.2nm) and broadest size distribution compared with those synthesized with ethanol and isopropanol. DBT was converted completely within 2.8min with an initial concentration of 20ppm, and 100% discoloration of MO was obtained after 40s. The highly efficient microreactor is easy to be integrated on a large scale, thus providing a highly promising alternative for a broad range of catalytic applications.