Methylene blue removal via photocatalysis by continuous tubular photoreactor with TiO2

Abstract

The Indonesian batik industry has dominated the global market with an export value in 2022 of around US$ 25.31 million or Rp 392.74 billion. Environmental implications are also substantial, as 10–20% of the total dye products utilized in batik dyeing are typically lost in effluent and discharged into bodies of water. Photocatalysis with TiO2 has been widely studied as a method that can be applied to wastewater treatment because it has high photoreactive properties and chemical stability compared to other materials. A tubular photoreactor system with continuous flow for processing dye waste in the batik industry has been successfully developed. This equipment consists of five reactors arranged in parallel connected by a 1/2-inch pipe and equipped with a circulation pump, flowmeter, feed tank, panel box, and flow valve. This system is used for the photocatalysis process with a TiO2 catalyst dose of 1.5 gr/l with flow rate variation. The results show that the color of the solution changed and the results of measurements using UV-VIS showed that the concentration of methylene blue decreased from 4.871 ppm to 0.081 ppm with the flow rate of 3 L/min. The kinetic constant for this variable is 0.01762/min with R2 = 0.98675.