When purchasing carbon anode scrap (a byproduct of aluminum smelting), you must prioritize Fixed Carbon content, which should ideally be above 97% or 98%. Other critical parameters include Sulfur content (typically <2.0% or <3.0% depending on grade), Ash content (<1.0%), and Volatile Matter (<1.0%). For metallurgical or fuel applications, the Calorific Value (often >7500 kcal/kg) and Moisture levels (<1.0% for dry scrap) are essential to ensure high thermal efficiency and low impurity injection in furnaces.