A novel method for highly effective removal and determination of binary cationic dyes in aqueous media using a cotton-graphene oxide composite.

The presence of dyes in industrial wastewater is a serious problem that hazards the surrounding environment. Therefore, this work investigates the removal of a binary dye system composed of Methylene Blue (MB) and Crystal Violet (CV) using an innovative composite (cotton fiber-graphene oxide (C-GO)). The simultaneous determination of the concentrations of the dyes in the binary system is a challenge. Thus, a new method was investigated to simultaneously detect the concentration of the dyes in the binary system using first-order derivative UV spectra to avoid the complex overlap of the maximum peaks in the original zero-order absorption spectra. Different parameters affecting the filter sorption mode, such as the concentration of the dyes, the dose of the (C-GO) composite, the dose of NaCl, flow rate, temperature, and pH, were investigated. The data obtained showed high adsorption efficiency for the binary dye system (>99%). This was approved based on the maximum sorption capacity (°) value obtained for the Langmuir model. Furthermore, this technique was developed, evaluated and applied to treat real industrial waste. The obtained data showed that the C-GO composite was highly efficient in treating industrial wastewater containing such dyes when a sufficient quantity is used. Therefore, it can be used as a promising adsorbent for such dyes in wastewater treatment processes.