Bleaching was performed conventionally with Chlorine and its compounds. These bleaching agent yielded high bleaching efficiency at room temperature and with lower consumptions of chemicals but consumed huge amounts of water and resulted immense quantities of water containing numerous hazardous compounds. Hydrogen peroxide replaced these agents but its chemistry restricted its use it requires high temperature and pH control despite which it cause tendering effect. Ozone has now been recognized as an excellent bleaching agent with high efficiency for and sorts of fabrics as well as paper pulp. It consumes lesser water, energy and additional chemicals and saves cost of bleaching. This study examined improvement in ozone bleaching efficiency with the addition of isopropanol and sodium boro hydride and the quality of effluent generated in comparison with hydro peroxide bleached effluent. Absorbency and whiteness and burst strength were the bleaching efficiency parameter and EC, turbidity, TDSand COD were the effluent quality parameters, considered in this study. AATCC standard methods and APHA standard methods were used in the analysis. Absorbency was measured with the stop watch, whiteness was measured withDatacolor SF 600+, burst strength was measured with machine Version 9.0.0.37977, CRT ball burst test. Machine type: Titan- Universal strength Tester by James. H. Heal & Co. Ltd (Standard ASTM D3787) and TDS was measured gravimetrically, COD was measured by titration, EC was measured with EC meter(HI 8633 meter) and turbidity was measured with turbidity was measured with turbidity meter (HI 93703 MICROPROCESSOR TURBIDITY METER).Description and inferential statistical analyses were applied using SPSS 20 and MINITAB-17.Results show that the different additives and their concentrations in the bleached water bath strongly influence the test
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parameters except for absorbency.Methanol has been found as the best additive for all the parameter (bleaching efficiency) on the basis of the average performance of the additives. Increase in its dose causes increase in whiteness(65.02 WCIE compared to 50.56 WCIE with blank) and the burst strength (95.5 lbf compared to 87lbf with blank) as well as improvement in absorbency (12sec compared to 50sec with blank) since it increases ozone stability and selectivity assisting it in bleaching. Oxalic acid, due to its acidic nature, has caused decrease in whiteness(40.92 WCIE compared to 50.56 WCIE with blank)and strength (78.24lbf comparedto 87lbf with blank) due to ozone hydrolysis. Isopropanol has shown a trend similar to methanol since it is also an alcohol and acts as scavenger for OH radical. Sodiumborohydride has also shown a similar trend. It help ozone access fabric micro-pores and remove impruties, it has resulted increase in fabric strength (89.39lbf compared to 87lbf with blank)and whiteness(59.54 WCIE compared to 50.56 WCIE with blank)with higher dose. All the additives have shown increase in pollutant concentration in the effluent with increase in their concentration in the bleach water bath since they have assisted ozone in performing its bleaching function.