In a single-stage fabric preparation process, the rate of decomposition of sodium hypochlorite is high at pH 9 compared to pH 10 and 11, both in the absence and presence of cotton. The extent of chlorate formation is high in the absence of cotton, whereas oxygen evolution is greater in the presence of cotton. The degradation of cotton is minimum at higher alkaline conditions. Around 30-35% more sodium hy pochlorite is required in the single-stage process compared to conventional bleaching.
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