Functions, advantages and disadvantages of bleaching chemicals Chemica Function Pul Advantage disadvantag pS es Na2S20 Reduce and MEasy to use;Decomposes decolorize ow capital readily Limited lignin in high cost brightness gain yield pulps Xylans Catalyze xylan c Easy to use; Limited hydrolysis and ow capital effectiveness aid in lignin cost COS removal NaOH Hydrolyze C Effective Darkens pulp chlorolignin and solubilize Economic lignin al EDTA Removal Improves Cost peroxide DTPA meta selectivity andChemica l Function Pul p Advantage s disadvantag es Na2S2O 4 Reduce and decolorize lignin in high￾yield pulps M Easy to use; Low capital cost Decomposes readily; Limited brightness gain Xylanas e Catalyze xylan hydrolysis and aid in lignin removal C Easy to use; Low capital cost Limited effectiveness; cost NaOH Hydrolyze chlorolignin and solubilize lignin C Effective Economic al Darkens pulp EDTA DTPA Removal metal ions C Improves peroxide selectivity and efficiency Cost Functions, advantages and disadvantages of bleaching chemicals