Enhanced photocatalytic degradation of methylene blue using MWCNTs
Hussein A. Khalaf, Rawaa A. Faris
Abstract
• Methylene blue (MB) is a carcinogenic pollutant widely known for its hazardous impacts on humans and marine life. • This study highlights the fundamentals and factors involved in the degradation reaction of MB. • Although the removal methodologies of adsorption and catalytic degradation are also one of the most widely reported removal methodologies in the case of dyes, the photocatalytic removal of the pollutants possess several advantages (including utilization of renewable resource (sunlight), Laser light. The presence of dyes, medications, and a number of other contaminants in wastewater is crucial due to the negative effects on human health and the environment. This study investigates the effect of different wavelengths of laser and sunlight on the degradation process of Methylene blue dye in the presence of MWCNTs. Different exposure time of sunlight and laser light (30, 60, 120, 180, and 240) minutes were utilized to induced MB photodegradation. The results show that both the diode laser 632 nm and sunlight were more efficient in degrade the Methylene blue (MB) dye. Kinetic analysis shows that the degradation follows pseudo-second-order model. In these findings, when MB solution exposed to sunlight for 240 min, the maximum dye degradation rate was 71.5 % after adding 0.0 75 g of MB. When exposed to a diode laser with a wavelength of 632 nm for 240 min, the maximum degradation rate was 79.69 % and 80.91 %, respectively, with 0.125 g of MWCNTs, which can provide reference for practical application.