Hierarchical structures based on natural carbons and zeolites

Abstract

Hierarchical porous structures have been widely synthesised to provide the most beneficial flow and surface area characteristics for a range of liquid and gas phase processes. We present three novel hierarchical porous structures based on carbonised olive seeds, coconut shells and coconut fibres coupled with zeolite Y. The structures are synthesised using a new seeding technique based around milling commercially available zeolite Y to provide nano-seeds for the growth step. The efficacy of the structures for the removal of ionic cobalt and arsenic contaminants is demonstrated with complete arsenic removal at simulated pollution levels. In addition, the vitrification of the structures to completely encapsulate cobalt ions, allowing no detectable release, is also described. All steps of the synthesis are tailored to produce the most economically viable materials using inexpensive starting materials and replacing, costly, colloidal seeds of zeolite Y with ball milled replacements.