Degradation of Rhodamine B dye in aqueous medium using electro-Fenton and sono-electro-Fenton process.

The electrochemical degradation of tetraethylrhodamine, commonly known as Rhodamine B (RhB) in acidic aqueous solutions, was examined utilizing a platinum grid anode and a stainless steel cathode. This dye is a substance used to impart color to cotton, silk paper, bamboo, weed, leather, and other materials as well as to prepare carbon paper, ball pen, stamp pad inks, paintings, etc. In case of being swallowed by humans and animals, this chemical compound causes an irritation to the skin, eyes, gastrointestinal and respiratory tract, in addition to phototoxic and photoallergic responses. Experimental evidence of carcinogenicity, reproductive and developmental toxicity, neurotoxicity, and chronic toxicity in people and animals has been established. The effects of various experimental parameters on the RhB dye degradation were investigated. The optimum conditions are: a current of 100 mA, Fe(II) = 10 mg/L, and Na2SO4 = 10 mg/L. All the experiments were carried out at pH = 2.5. The % removal = 98.75 after 120 min. The combination of electro-Fenton and ultrasonic irradiation with a low frequency (sono-electro-Fenton process) was also studied. Sonoelectrochemical treatment of RhB-contaminated water yielded a significant, considerable percentage of 99% after 90 min at a current of 100 mA. [ABSTRACT FROM AUTHOR]