Carbon Filters Effects of Starting Material on Activated Carbon Characteristics and Performance

The objective of this article is to demonstrate how the choice of starting material determines potential carbon product properties. Activation can only "develop " an activated carbon skeleton, using the building blocks supplied by the original starting material. The resultant activated carbon skeleton defines the adsorption pore structure and thus all the physical adsorption characteristics of the ensuing activated carbon products, and these in turn dictate the performance of the activated carbon product in any application. This article gives evidence of the effects of starting material selection on the adsorbing pore structure of activated carbon, the resultant performance for removal of trace levels of volatile organic compounds (VOCs) from water, and de-chlorination efficiencies and effectiveness in de-chlorination applications. This evidence will demonstrate the importance of proper starting material selection in determining the optimal carbon for process water treatment applications. Activated carbon can be described as a crude graphite. Graphite is the material used as a lubricant and as the "lead " in pencils. Activated carbon and graphite are among the few pure forms of carbon, with almost not nitrogen, hydrogens, sulfur, or oxygen (as produced). From the perspective of a chemist, activated carbon is an imperfect form of graphite. Its chemical bonding is much like graphite, but it has a fixed rigid structure, no lubricating properties (it’s actually abrasive in nature), and several other non-graphitic properties. What is Activated Carbon? Activated carbon also has a more random carbon structure than graphite, and is often referred to as amorphous carbon. This structure results in a high degree of porosity, with more than a million-fold range in pore sizes. The pores range from visible cracks and crevices, to gaps an