Kinetics and Products Distribution Study on the Catalytic Effect of Zn/HZSM-5 over Pyrolysis of Chlorella through TG-FTIR and Py-GC/MS

In this study,both the pyrolysis and catalytic pyrolysis behaviour of chlorella were investigated using thermogravimetric analysis combined with Fourier Transform Infrared spectrum(TG-FTIR)and Py-GC/MS.The results of TG indicated the pyrolysis of chlorella was divided into three stages,and the Coats-Redfern kinetic model was used for the analysis and validation of the obtained thermal data.The regression coefficients indicated that the pyrolysis of chlorella was close to second-order reaction.The activation energy of pyrolysis of chlorella and catalytic pyrolysis of chlorella+HZSM-5,chlorella+Zn/HZSM-5 was 61.645,59.080 and 56.808 kJ·mol^(−1),respectively.Combined with the data of FTIR,we found that the addition of the HZSM-5 effectively reduced the activation energy required by pyrolysis;the addition of the Zn/HZSM-5 could not only reduce the activation energy,but also reduce the yield of oxygen-containing compounds,increase the emissions of CO_(2),and facilitate the production of high value-added hydrocarbon products.These results were also verified by Py-GC/MS that the addition of Zn/HZSM-5 could reduce the formation of ketones and aldehydes and increase the production of nitrogen-containing compounds.Thus,through the catalytic pyrolysis of chlorella,the utilization range of chlorella can be expanded,and better bio-oil can be obtained,which will play a crucial role in the selection of available energy in the future.