phosphate in a phosphoric acid activated carbon in a third approach phosphoric acid is added to an activated carbon that already contains some residual phosphoric acid such as wood based wv b and wv a 1100 from meadwestvaco corporation or does not contain any substantial amount of phosphoric acid such as steam activated coal based cpg from calgon corporation or wood based tac 900 from meadwestvaco corporation the added phosphoric acid is subsequently converted to a polymerized phosphate by a heat treatment as described in the first approach finally one or more transition metals can be added to an activated carbon that already contains some residual transition metals such as steam activated coal based cpg from calgon corporation or wood based tac 900 from meadwestvaco corporation or does not contain any substantial amount of transition metals such as wood based wv b and wv a 1100 from meadwestvaco corporation in these last two approaches there may some synergy achieved for improved hydrogen fuel purification decolorization when phosphoric acid is added to an activated carbon with residual transition metals present or when a transition metal usually in salt form is added to an activated carbon with residual phosphoric acid the following examples.