| It is in order to find the catalytic which is good of activity, stability, wide applicable scope and low cost from the role which catalyst plays in the advanced oxidation treatment of refractory wastewater. Tn turn, in view of the complex and changeable sewage system, the utilization of oxidants is improved in the advanced oxidation technologies, the reaction condition,the requirement to the reaction equipment and the investment and operation cost are all reduced and the application range of the technology is expanded by adding the catalyst.In this paper, homogeneous and heterogeneous catalytic which are suitable for the advanced oxidation treatment of styrene butadiene rubber wastewater are explored in order to study the effect of H2O2utilization,based on the advanced Fenton oxidation catalytic oxidation technology. the main conclusions are as follows:(1) Under the condition of laboratory, in view of500ml rubber wastewater, the optimum processing conditions discussed of fenton reagent degrading rubber wastewater by single factor and orthogonal test analysis are45℃,60min, pH being between3to7,1.65mmol of FeSO4,2ml of H2O2;under these conditions,55%CODcr of raw water is removed,biodegradability of wastewater is increased.(2) Combining with the wastewater characteristics of the synthetic rubber company and the actual process,the more economic and feasible conditions are3.3mmol/L of FeSO4, the mole ratio of H2O2/Fe2+being between9to11,60min, temperature and pH are no less than raw water.(3) Analysing the catalytic activity of a variety of non noble metal ions, catalytic activity of Cu2+and Mn2+are effective to treat the wastewater. while rubber wastewater is processed by homogeneous fenton catalytic oxidation, ensuring the total amount of activity ion eaually, each utilization of H2O2is not identical and effluent CODcr of wastewater has bigger difference when the active tions are in different proportion of compound as catalyst; According to the Fe2+/Cu2+=1:1and Fe2+/Cu2+/Mn2+=2:2:1, compared with the separate of Fe2+, the degradation rate of CODcr are increased by13%and17%respectively.(4) The catalytic activity of single metal oxide as a kind of Fenton catalysts is not high, the catalytic activity is Fe2O3>CuO> MnO2> CeO2> ZnO, and CeO2and ZnO as catalytic3degrading styrene-butadiene rubber wastewater show almost no activity.(5) According to the specific surface area and holes requirements of the load type catalyst carrier, this paper selects the20～40C, r-Al2O3, diatomite, NaY molecular sieve as the carrier of catalyst.(6) Analyzing the activity and stability of eight group catalyst which are prepared by a dollar or multivariate composite active components with the four kinds of carrier, the activity of Fe2O3-CuO/C catalyst is best, removal rate of CODcr reaches72%. All other things being equal, when the removal rate of CODcr exceeds65%,the dosage of activated carbon catalyst,molecular sieve catalyst, diatomite catalyst and r-Al2O3catalyst is16g/L,20g/L,24g/L and36g/L respectively.(7) For ternary composite catalyst of Fe2O3-CuO-MnO2/C,the preparation conditions of roasting temperature, roasting time, the concentration of the pickling liquid are studied by single factor experimental and the orthogonal test of three factors and three levels and preparation conditions of roasting temperature affects the most significant, next is calcination time, the concentration of the pickling liquid; the optimum preparation conditions of composite catalyst are500℃of roasting temperature,4h of roasting time,8%of the concentration of the pickling liquid; for catalyst dosing quantity, the additive amount of hydrogen peroxide, reaction time with three levels and three factors orthogonal analysis,under the conditions of60min of reaction,4ml/L of hydrogen peroxide,16g/L of catalyst,the removal rate of CODcr reaches73.59%Fe2O3-CuO-MnO2/C involvement in catalytic oxidation reaction.(8)The content of Ce is examined on the effect of the stability of the ternary composite catalyst activator, when addition amount of Ce is0.4%, the activity of Fe2O3-CuO-MnO2-CeO2/C catalyst is best, the removal rate of CODcr reaches80%.(9) The activity,stability of one yuan, binary, ternary and quaternary active carbon catalyst are investigated and the adsorption of the activated carbon is individually examined,Fe2O3-CuO-MnO2-CeO2/C catalyst has the best activity and stability;when used after10times in a row, CODcr removal rate of Fe2O3-CuO-MnO2-CeO2/C catalyst still reach more than60%; the removal rate of CODcr is28%depending on adsorption of activated carbon when the using time is N=1;while N<6, the catalytic role of catalyst plays together with the adsorption of active carbon, but the catalytic role dominates;when N>6, the adsorption of activated carbon tends to saturation, basically,no longer acting as adsorption removal of CODcr. |
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