Development of a Laboratory-Scale Electrochemical Mercerization and Bleaching System for Technological Evaluation

The development objective is aimed to provide a laboratory-scale ecological bleaching and mercerization process for replacement of the conventional polluting process, which are often employed harmful oxidants such as hypochlorite, hydrogen peroxide or perborates, perphosphates to remove colour from the mercerized cotton fabric. This bleaching process generates large quantities of waste water and requires high pollution treatment cost. In addition, the consumption of large amount of bleaches causes high production cost. The proposed electrochemical process could offer a cleaner production process as it doesnot need any harmful chemicals. The process offer the advantages of low cost, low power consumption and pollution free. In this electrochemical system which uses a proton exchange membrane to separate the cathode and anode respectively, fabric moves through both the cathode compartment and the anode compartment. In the cathode compartment, oxygen gas is reduced to form the hydroxide and hydrogen peroxide for preliminary bleaching and mercerization of the fabric where the anode will generate the hypochlorite for second stage bleaching. As estimation, the proposed technology would lead to 40% integrated cost reduction due to substantial saving in energy, effluent, and chemicals.