Application of the Catalyst MnTACN onto Cotton Fabric as a Novel Approach in the H2O2/UV Decolourisation Process

In this article a novel approach for a catalytic advanced oxidation process using H 2 O 2 /UV/MnTACN is investigated, for the decolouration of Reactive Blue 4 (RB4) containing wastewater at room temperature. The catalyst 1,4,7-trimethyl-1,4,7-triazacyclononane (MnTACN) was not added to the batch reactor where the advanced oxidation process (AOP) was carried out conventionally, but was first applied to the cotton fabric to form a suitable catalyst carrier with a high specific surface area. With the given experimental parameters (0.777 g/ l H 2 O 2 ; a mercury (Hg) lamp at 500 W; 40 mg/ l solution of Reactive Blue 4; room temperature), complete decolourisation with the MnTACN catalyst was achieved in only 20 minutes. When the MnTACN catalyst adsorbed on the cotton fabrics is introduced into the process as a functional textile material, the decolouration of RB4 is much faster, and 100 % decolouration is achieved in 10 minutes. Although pretreatment of the fabric with acid and/or UV/ozone before application of MnTACN influences the amount of adsorbed MnTACN, the decolouration process is almost unaffected over time. Pre-treatment of fabric with chitosan before the application of MnTACN affects the final decolourisation rate and efficiency negatively, and does not act synergistically with the MnTACN. The same functional fabric with adsorbed MnTACN can be used in at least 5 consecutive AOPs, which makes the process more environmentally friendly and cost effective, but also opens the possibility to a continuous wastewater treatment process.