Deliverables A new textile effluent treatment process using immobilised enzymes Catalases were immobilised on alumina, which increased their stabilities. A horizontal and a vertical packed-bed enzyme reactor were constructed for the continuous degradation of hydrogen peroxide. An alumina based carrier material was developed with special shapes in order to ensure oxygen release from the reactor. Catalase treated bleaching effluents were used for lab-scale dyeing and it was shown (evaluation based on dE values), that acceptable staining levels can be obtained provided that the dyeing protocols are adjusted accordingly. The process was shown to be economically attractive for effluent treatment for reuse in dyeing especially in continuous bleaching/washing. Exploitable results Process for dye protection to the attack of peroxide, perborates or percarbonates Bleaching cotton with peroxide can affect the subsequent dyeing with reactive dyes. For this reason it is necessary to wash very well the material after bleaching, using a lot of water in the process. Reducing agents or enzymes that can be used to destroy the peroxide, or/and acid to neutralise the material. All these are however extra steps needed, which means time spent filling and emptying the machine and in the process itself, and extra water and energy. With bleaching after dyeing all these steps are avoided. For PE/CO blends the peroxide also clears the excess disperse dye substituting the reducing agent, hydrosulphite, which is very poluting. It also shortens the process since it does away with the intermediate rinsing.For these blends milder oxidants such as perborate can be used since whiteness of the cotton component is not so relevant, which means that a greater nunber of reactive dyes can be used. Searching for OpenAIRE data... There was an error trying to search data from OpenAIRE No results available
