A　series　of　Co-La　catalysts　were　prepared　using　the　wet　impregnation　method　and　the　synthesis　of　catalysts　were　modified　by　controlling　pH　with　the　addition　of　ammonium　hydroxide　or　oxalic　solution.　All　the　catalysts　were　systematically　investigated　for　NO　oxidation　and　SO2　resistance　in　a　fixed　bed　reactor　and　were　characterized　by　Brunanuer-Emmett-Teller　(BET)　method,　Fourier　Transform　infrared　spectroscopy　(FTIR),　X-ray　diffraction　(XRD),　Thermogravimetric　(TG)　and　Ion　Chromatography　(IC).　Among　the　catalysts,　the　one　synthesized　at　pH　=　1　exhibited　the　maximum　NO　conversion　of　43%　at　180　degrees　C.　The　activity　of　the　catalyst　was　significantly　suppressed　by　the　existence　of　SO2　(300　ppm)　at　220　degrees　C.　Deactivation　may　have　been　associated　with　the　generation　of　cobalt　sulfate,　and　the　SO2　adsorption　quantity　of　the　catalyst　might　also　have　effected　sulfur　resistance.　In　the　case　of　the　compact　selective　catalytic　reduction　(SCR),　the　activity　increased　from　74%　to　91%　at　the　highest　gas　hourly　space　velocity　(GHSV)　of　300000　h(-1)　when　the　NO　catalyst　maintained　the　highest　activity,　in　excess　of　50%　more　than　that　of　the　standard　SCR.　(C)　Higher　Education　Press　and　Springer-Verlag　Berlin　Heidelberg　2016