Fast removal of methylene blue from aqueous solution using porous soy protein isolate based composite beads

Soy protein isolate (abbreviated as SPI) was chemically immobilized on deacetylated konjac glucomannan (abbreviated as DKGM) in the current work. The obtained porous SPI/DKGM composite beads were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR) and zeta potential analysis. Adsorption performances of porous SPI/DKGM composite beads were tested to remove methylene blue from aqueous solution. Benefiting from the combined merits of SPI, high adsorption capacity and fast adsorption of methylene blue (MB) by porous SPI/DKGM composite beads are achieved. The maximum methylene blue adsorption capacities were shown to be 272.4   mg   g −1 for porous SPI–DKGM composite beads. These results confirm that the porous SPI–DKGM composite beads have a potential for methylene blue removal from wastewater.