In this study

Nannochloropsis sp. (NS) and walnut shell (WS) were used as raw materials for mixed pyrolysis

and the characteristics of thermal demanding during pyrolysis of NS

WS and NS/WS were initially investigated by a thermogravimetric analyzer and a fixed-bed reactor. Then the effects of mass ratio

reaction temperature

and catalysts on the preparation of aromatic hydrocarbons from NS/WS mixed pyrolysis were studied by a GC/MS method. Results showed that the two endothermic peaks were observed from WS pyrolysis at 180-270℃ and 380-485℃

the overall performance of WS pyrolysis took on the endothermic effect with thermal demanding values of 378.56-596.45 kJ·kg-1 under different heating rates. An endothermic peak was obtained from NS pyrolysis at 280-450℃

the overall performance of NS pyrolysis took on exothermic effect with thermal demanding values of -814.76——1191.52 kJ·kg-1. The pyrolysis of NS/WS presented low exothermic effect with thermal demanding values of -99.05——158.04 kJ·kg-1

indicating that the mixed pyrolysis achieved a certain degree of thermal coupling. The mixed pyrolysis of NS/WS demonstrated a synergistic effect in the preparation of aromatic hydrocarbons. The optimum condition for aromatics preparation with a value of 20.51% was achieved at a temperature of 600℃ and a NS/WS mass ratio of 1:1. By introducing Cu/HZSM-5 catalyst

the relative content of aromatics was further improved (35.74%). This study provided a new approach for high-value utilization of NS and WS.