Waste rice straws were converted into rice straw derived activated carbon(RSAC)

which supported ferric oxides(Fe3O4

loaded dosage of 14.25%) as ozone catalyst with 1175.1 m2·g-1 of specific surface area

and efficiency of heterogeneous catalytic ozonation of biologically pretreated paper-making wastewater were investigated.The results indicated that RSAC and catalyst all had the good adsorption capacity of biologically pretreated paper-making wastewater

and the adsorption isotherms fitted well with the Langmuir model(R2>0.99).The addition of the prepared catalyst significantly enhanced the pollutants removal performance of ozonation of raw wastewater

and the COD

BOD5

NH4+-N and chromaticity in the treated effluent were 46

17

5 mg·L-1 and 18 degree which all met discharge standard paper-making wastewater(GB 3544-2008) with the optimal operating parameters(0.3 g·h-1 of ozone dosage and 1 g·L-1 of catalyst dosage and raw wastewater pH).Moreover

the catalyst had superior stability and leaching of metal irons were very few at 20 cycle's utilization.It was deduced that the enhancement of catalytic activity was responsible for generating more radicals by radical scavenger and ESR detection.Thus

the prepared catalyst with efficient

stable and economical advantages was suitable for catalytic ozonation of biologically pretreated paper-making wastewater.