Pyrolysis of rubber seed oil over high-temperature copper slag: Gas and mechanism of coke formation

Abstract

In the process of direct use and upgrading of rubber seed oil (RSO), coke formation is a severe problem. Therefore, evolution of the cokes structure is a key factor affecting the efficient utilization of RSO. This study investigates the production of coke during RSO pyrolysis. All cokes are analyzed and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, CHNS/O analysis, and Raman. The results indicate that cokes on the surface of copper slag (SCS-cokes) are coral-like and the surfaces are relatively rough while cokes on the quartz tube wall (QTW-cokes) have a flat structure. According to FT-IR (500–4000 cm−1), QTW-cokes and SCS-cokes contain a variety of O-containing functional groups. Raman spectra indicate a decrease in the total band area with increasing temperature due to the loss of O-containing functional groups at high temperature. The small aromatic ring systems in cokes are transformed into the large aromatic ring systems. In addition, the yields of pyrolysis gas and cokes increase with increasing temperature, while the opposite is true for tar. RSO pyrolysis products also have value for further processing. Therefore, there is great potential for the co-treatment of CS with RSO.