Investigation of single stage bleaching of bacterial celluse

In this thesis study, purification of bacterial cellulose produced by fermentation with ethyl alcohol and sodium hydroxide stages, bleaching with sodium borohydride, sodium percarbonate and hydrogen peroxide stages were studied. Optical properties of the test papers produced within the scope of the study were measured and FTIR-ATR and SEM characterizations were performed. In the study, the color change effect of the purification process compared to the control (ΔE) was determined as 29.34. The highest ISO brightness result in the study was determined as 70.82% in the test samples to which 2% active oxygen containing hydrogen peroxide and 1.5% sodium hydroxide were applied. Successful results were also obtained with the alkaline sodium percarbonate application used as an alternative to hydrogen peroxide. ISO brightness value was measured as 68.9% with the sodium percarbonate application containing 3% AO. The best results in terms of yellowness value were obtained in test samples to which hydrogen peroxide containing 2% active oxygen and 1.5% sodium hydroxide were applied. It was determined that sodium percarbonate application partially increased the yellowness value compared to hydrogen peroxide. As a result of SEM image analysis of the test samples, it was also determined that the applied processes did not damage the structure of the fibers.