Anatase TiO2 was immobilized on a silicate fabric with the water glass binder and used in a photocatalytic flow reactor (295 mm in length, 68 mm in diam., Hg lamp, irradn. wave length 250-800 nm) for decompn. of the Acid Red 18 dye in aq. soln. (initial concn. 10 mg/L, soln. vol. 2 L, recilculation How 36 L/h). The full decoloration of the soln. was achieved after 20 h in the first test and after 15 h in the next tests. The reaction rate const. for the first test was 0.2772/h and for the third one 0.1934/h.