(32e) Kinetic Study of Degradation of Pharmaceutical Drugs By Ozone Microbubbles

Surabhi Patel¹, Rohit Agarwal¹, S. K. Majumder^1*, P. Das² and Pallab Ghosh¹

¹Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati-781039, India, Email: p.surabhi@iitg.ernet.in; agarwal.rohit@iitg.ernet.in; skmaju@iitg.ernet.in; pallabg@iitg.ernet.in;

²Department of Chemical Engineering, Jadavpur University, Kolkata-700032, India, Email: papitasaha@gmail.com

*Corresponding and presenting author’s email: skmaju@iitg.ernet.in

The frequent occurrence of pharmaceuticals in the aquatic environment as well as in drinking water has raised a concern about their potential impact on environmental and public health. However, their elimination using conventional treatment methods has not been an easy task. The study on the kinetics of ozonation by ozone microbubbles for pharmaceutical drugs at room temperature is reported in this present work. The results showed that at pH 5, the ozonation of carbamazepine in aqueous solution reduced the concentration to about half of its initial value which was 6.35×10^-5 M. As per model, the rate constant for carbamazepine is found to be 5.638×10^-1 M^-1s^-1. The concentration of ibuprofen (IBP) in aqueous solution reduced from 3.6×10^-6 M to 0.26×10^-6 M in 41 munites which reflects 92.2% removal. The estimated value of second order rate constant for IBP is 11.58 M^-1s^-1 at pH 5. In case of methylisothiazolone (MIT) it is observed that its concentration reduced from 10×10^-6 M to 0.32×10^-6 M in 50 s. In this case the calculated value of second order rate constant for MIT is 138.12 M^-1s^-1at pH 5. In case of ranitidine the value of pseudo first order rate constant ‘k_obs’ is increasing from 0.01505 s^-1 to 0.03961 s^-1 with increasing inlet ozone concentration at pH 5 while the value of second order rate constant ‘k’ is decreasing from 144.43 M^-1s^-1 to 95.03 M^-1s^-1with increasing inlet ozone concentration. The present study may be helpful for further understanding the advanced oxidation of phermaceutical drugs to impliment ahead the wasteawter treatment processes.

KEY WORDS: Ozonation, microbubble, pharmaceutical drugs.

REFERENCES:

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