Carbon precursors in coal tar: Extraction and preparation of carbon materials

Coke resources are abundantly available worldwide and are a large by-product of tar production. Moreover, their utilization presents a series of environmental pollution problems. Common technologies for coal tar production applications urgently need to be upgraded because coal tar is listed as a national hazardous waste. This review associates coal tar development with deep processing technology for extracting environmentally beneficial compounds from coal tar, which have never been reported. Recent studies on the innovative approaches for extracting phenols and nitrogen-containing compounds from coal tar have been addressed, as well as a preparation method of carbon materials with high catalytic activity and a well-ordered structure by confined polymerization. Tremendous demand for further research and exploration of selectively extracted compounds from coal tar implies a new opportunity for polymerizing the resin and a great challenge for the current technology implemented for valorizing coal tar into ordered carbon materials. Consequently, more concerted efforts should be implemented to achieve a wide range of polymer resin applications and improve the quality of carbon precursors extracted from the coal tar, thus increasing the economic benefit and scientific value of coal tar.