Fabrication of the annular photocatalytic reactor using large-sized freestanding titania-silica monolithic aerogel as the catalyst for degradation of glyphosate

A facile one pot method has been applied to fabricate large-sized freestanding titania-silica monolithic aerogels (TSMA). The obtained TSMA was characterized by scanning electron micrograph (SEM), Energy dispersive spectrometer (EDS), X-ray powder diffraction (XRD) and nitrogen adsorption measurements. SEM results show the TSMA has bicontinuous inner structure and large macropores (through-pores), which are favorable for the liquid infiltration. XRD results demonstrate the TSMA is anatase and nitrogen adsorption results reveal its high specific surface area of 445.9 m 2 /g. To maximize the catalytic activity of the as-prepared TSMA, an annular photocatalytic reactor has been specially designed and fabricated. With the apparatus, the as-prepared TSMA exhibited outstanding catalytic performance, which degraded glyphosate completely within 180 min of photocatalytic reaction. The kinetic rate (k value) of the photocatalytic reaction reaches 0.0242 min −1 . Ion chromatography results indicate that glyphosate was mainly mineralized to inorganic ions such as PO 4 3− and NO 3 − , etc.