Research On Pyrolysis Characteristics Of Waste Tires

In this paper,we aim to improve the efficient utilization of pyrolysis products of waste tires by co-pyrolysis and catalytic pyrolysis.Activated carbon which was prepared from waste tires catalytic pyrolysis carbon,and the physical and chemical properties of the prepared catalyst and activated carbon were characterized by Brunnauer-Emmett-Teller(BET),X-ray diffraction(XRD)and Scanning electron microscopy with energy dispersive X-ray Spectroscopy(SEM-EDX).The effects of biomass(walnut shell,rape straw,corn cob)and components(cellulose,hemicellulose,lignin)and catalysts on the thermal properties,the release characteristics of volatile products,the component of pyrolysis oil were investigated by TG-FTIR,GC-MS and fixed-bed reactor and the optimum conditions of activated carbon adsorption crystal violet.(1)Co-pyrolysis results show that walnut shell and rape straw can effectively promote waste tires pyrolysis,while corn cobs inhibit waste tires pyrolysis and increase the content of corn cobs,which contributes to the generation of pyrolytic carbon.Different composition of biomass produce different gas,oil and carbon yields in the co-pyrolysis.Among them,the high proportion of cellulose in the walnut shell is conducive to obtain high yield of pyrolysis oil and corn corn with a higher proportion of lignin lead to higher char yield.The distribution of the co-pyrolysis oil shows that the addition of biomass can significantly improve the combustion efficiency of the pyrolysis oil by reducing the containging nitrogen and sulfur compounds.(2)The results of catalytic pyrolysis of waste tires revealed that Al2O3 and CoOx/Al2O3 catalysts inhibited the pyrolysis of waste tires and increased the yield of pyrolytic char.The evolution of CO2 was improve by adding CoOx/Al2O3 and Al2O3 catalysts and CoOx/Al2O3 catalyst could obviously increased the yield of H2O,CO,CH4,aliphatic and aromatic hydrocarbons.From the GC-MS analysis,it was found that Al2O3 and CoOx/Al2O3 catalyst can improve the quality of waste tire pyrolysis oil and increase the content of light fractions(ethylbenzene,o-xylene,styrene,alkyl-benzene,limonene),reducing the PAHs,containing S and containing N compounds.(3)Co/AC was prepared by waste tires catalytic pyrolysis,acidified and activated and the optimum conditions for the adsorption of crystal violet were as follows:the adsorption time was 2 h,the adsorption temperature was 30?,the adsorption dosage was 2 g/L and adsorbate concentration of 280 mg/L.