Extraction of indium from sulfuric acid solutions to carbon composites modified with nanotubes

The regularities of the sorption extraction of indium from sulfuric acid solutions using composites based on activated carbons modified with carbon nanotubes are considered. Their surface was studied by scanning electron microscopy. The equilibrium and kinetic characteristics of the sorbents are obtained. Indium sorption isotherms have a convex shape and are described by the Langmuir equation. The approximation of kinetic data using pseudo-first and pseudo-second order models, internal diffusion, and Elovich showed that the highest correlation coefficient is observed when using a pseudo-second order model. The process of indium sorption is limited by external diffusion. The efficiency of the carbon composite during the extraction of indium in four sorption-desorption cycles has been verified.