“…However, the pyrolytic gas and tar mainly composed of light alkenes, aromatic long chain alkenes and light alcohols will inevitably bring the cost and burden of secondary pollutant treatment. [14] In addition, some innovative experiments were performed by different research groups, involving low-temperature molten salt technology, [15] cryogenic grinding, [16] eddy current separation, [17] ultrasonic-assisted acid scrubbing, [18] aqueous exfoliating and extracting solution (AEES) [19] and waste oilbased methyl ester solvent. [20] Figure 1 shows these innovative explorations in latest years.…”