Catalytic fast co-pyrolysis (co-CFP) of bamboo sawdust and waste tire over HZSM-5 and MgO was conducted using a tandem pyrolysis and upgrading system which consists of a bubbling fluidized bed and a fixed bed reactor. HZSM-5 mixed and sequential with MgO modes were studied to explore the additive effect for the promotion of aromatic hydrocarbons. Experimental results indicated that co-CFP of bamboo sawdust with waste tire over pure HZSM-5 increased the yields of pyrolysis oil and char, while the gas yield decreased with the increasing of waste tire percentage in the feedstock blends. The product distribution of pyrolysis oil obtained from co-CFP of bamboo sawdust and waste tire over pure HZSM-5 was dominated by aromatic hydrocarbons, and the relative concentration increased from 26.71 to 71.50% as the waste tire percentage elevated from 0 to 60 wt%. Co-CFP of bamboo sawdust and waste tire using HZSM-5 mixed with MgO mode produced a higher yield of pyrolysis oil than the sequential mode when HZSM-5/MgO mass ratio was raised from 1:4 to 1:1. However, the sequential mode was proved to be more effective in the promotion of aromatic hydrocarbons than the mixed mode at a higher HZSM-5 proportion. A positive additive effect for alkylbenzenes was found when the sequential mode was used at varying HZSM-5/MgO mass ratios. Regarding the olefins, C10 olefins were main products, and limonene selectivity increased at first and then decreased with the highest selectivity of 38.87% occurring at HZSM-5/MgO of 2:3 in the mixed mode case. The additive effect of HZSM-5 and MgO indicated that both the mixed and sequential modes inhibited the formation of polycyclic aromatic hydrocarbons with the most significant additive effect obtained at HZSM-5/MgO mass ratio of 1:1 using the mixed mode.
Bibliographical noteFunding Information:
The authors are grateful for the National Natural Science Fund Program of China (No. 51776042 ), the Scientific Research Foundation of Graduate School of Southeast University ( YBJJ1646 ), the Scientific Innovation Research Program of College Graduate in Jiangsu Province ( KYLX16_0204 ) as well as the Financial Support from the Program of China Scholarships Council (No. 201706090032 ).
- Additive effect
- Bamboo sawdust
- Catalytic fast co-pyrolysis
- HZSM-5 and MgO
- Waste tire