Enzymatic Hydrolysis: A Novel Approach to Direct Dye Removal

Friday, February 17, 2017
Exhibit Hall (Hynes Convention Center)
Tiernan Kennedy, Wachusett Regional High School, Holden, MA
This purpose of this experiment was to test the effect of cellulase and dye concentration on direct dye removal from paper waste. This dye removal would in turn would render paper waste a superior refuse derived fuel. It was hypothesized that as the amount of cellulase increased, the extent of hydrolysis would increase, therefore the extent in which London dispersion forces and structure dependent hydrogen bonding are interrupted, therefore increase the amount of dye removed. It was also hypothesis that as the dye concentration increased, more dyes would be concentrated to the same area, and therefore more dye would be removed per each hydrolysis reaction.

To conduct the experiment, three groups of paper were dyes with different concentrations of dye, 0.0mL dye per 400mL of water, 1.5mL dye per 400mL water, 3.0mL per 400mL water. This paper was then hydrolyzed by 0.0g, 0.1g, 0.05, and 0.02g of cellulase at each dye concentration. 0.50g of paper was used for each reaction, which took place in the condition of a 5Ph buffer in a water bath at 55degC. After the reaction was complete, the absorption of the solution at 570 nm was measured using a spectrophotometer.

It was found that as the dye concentration increases there was a significant increase in absorption at 570nm. Although there was a significant change in the control dye group between the control concentration of cellulase and each other concentration of cellulase, there was not a statically significant positive trend, while there was in the 1.5mL and 3.0mL dye groups, which suggests that the amount of dye removed increased in proportion to the amount of cellulase. It was also found that as the dye concentration increased, there the amount of dye removed increased significantly as well as the ratio of amount of dye removed per gram of cellulase.