Co-carbonization of brominated petroleum pitch, coal tar pitch and benzoyl chloride to prepare cokes

After the quinoline insoluble fraction was removed, petroleum pitch (PP) was brominated under ultraviolet light irradiation for 3 to 9 h with a bromine to PP mass ratio of 1:20 to prepare brominated PPs (BPPs). Synthetic pitches (SPs) were produced from these BPPs by mixing them with refined coal tar pitch (RCTP) using a solvent (5 wt% benzoyl chloride)-assisted mixing method, using different mass ratios of BPP/RCTP, and BPPs with different irradiation times. The SPs were carbonized to prepare semicokes. The properties and carbonization behavior of the SPs were investigated by FT-IR spectrometry, 1H NMR, thermogravimetry and viscometry, and the optical texture of the semicokes was examined by polarized-light microscopy, X-ray diffraction and scanning electron microscopy. Results indicate that converting PP into BPPs increases its reactivity with RCTP, which is beneficial for developing an ordered texture during carbonization. A high-quality coke with a highest yield of 50.1 wt% was prepared from the optimum SP made from BPP brominated for 6 h and a mass ratio of BPP to RCTP of 1: 9.