Study of Photocatalytic Properties of Ag/AgCl-Decorated Soybean Protein Knitting Fabric Against Acid Blue 260 Dye by Factorial Design

Photocatalytic materials have been the focus of several studies due to their excellent optical photoexcitation properties for waste treatment. However, their use promotes the generation of inorganic secondary waste, due to their nanometric grain size, which can cause several environmental hazards. The optimization and immobilization of such photocatalysts for treatment after the catalytic process have thus attracted much attention. In this work, Ag/AgCl nanoparticles were immobilized by hydrothermal treatment on soybean knitted fabric. The photocatalytic activity of the resulting Ag/AgCl-functionalized soybean knitted fabric was estimated based on the reduction of the concentration of Acid Blue 260 dye. The response surface factorial design methodology was applied, varying the Ag/AgCl concentration, nanocatalyst immobilization time, and hydrothermal process temperature, to analyze the individual effect of and interaction between the variables, besides establishing a mathematical model of the process. The photocatalytic results showed that addition of Ag/AgCl to the fabric favored its use and reuse for the degradation of the Acid Blue 260 dye. The mathematical model together with the response surfaces showed that the residence time in the hydrothermal bath was the most significant variable in terms of the dye reduction, favoring this advanced treatment method.