Adsorption/desorption study of proteins onto multi-walled carbon nanotubes and amino multi-walled carbon nanotubes surfaces as adsorbents

Abstract Two proteins, i.e. bovine serum albumin and egg white lysozyme are used as model adsorbents for the food industry (dairy) wastewater and multi-walled carbon nanotubes (MWCNT) and amine functionalized multi-walled carbon nanotubes (MWCNT-NH 2 ) surfaces were used as adsorbents. Various effective parameters such as contact time, the initial concentration of proteins, initial pH levels, and temperature were well investigated and optimized using batch adsorption study. Upon optimization, it was observed that the on increasing the initial concentration the adsorption of both the proteins also increases. The equilibrium adsorption data of Lysozyme using MWCNTs and MWCNT-NH 2 as adsorbents were well fitted and in good agreement with the type (II) Langmuir isotherm model and Freundlich isotherm model, respectively, while on the other hand, for serum albumin adsorption using MWCNTs and MWCNT-NH 2 as adsorbents were described was well fitted and in good agreement with type (II) Langmuir isotherm model.