Ru-based　catalysts　for　catalytic　combustion　of　high-toxicity　Cl-containing　volatile　organic　compounds　are　inclined　to　produce　Cl-2　instead　of　ideal　HCl　due　to　the　Deacon　reaction.　We　herein　reported　that　the　three-dimensionally　ordered　macroporous　(3DOM)　WOx-supported　RuP　nanocatalyst　greatly　improved　HCl　selectivity　(at　400　degrees　C,　increased　from　66.0%　over　Ru/3DOM　WOx　to　96.4%　over　RuP/3DOM　WOx)　and　reduced　chlorine-containing　byproducts　for　1,2-dichloroethane　(1,2-DCE)　oxidation.　P-doping　enhanced　the　number　of　structural　hydroxyl　groups　and　Bronsted　acid　sites.　The　isotopic　1,2-DCE　temperature-programmed　desorption　experiment　in　the　presence　of　(H2O)-O-18　indicated　the　generation　of　a　new　active　oxygen　species　(OO)-O-16-O-18　that　participated　in　the　reaction.　Generally,　P-doping　and　H2O　introduction　could　promote　the　exchange　reaction　between　Cl　and　hydroxyl　groups,　rather　than　oxygen　defects,　and　then　benefit　the　production　of　HCl　and　reduce　the　generation　of　other　chlorine　species　or　Cl-2,　via　the　reaction　processes　of　C2H3Cl　-＞　alcohol　-＞　aldehyde　-＞　carboxylic　acids.