Development of synergistic extraction process for highly efficient removal of phenols from coal gasification wastewater

• Published in: Journal of cleaner production 2019-02, Vol.211, p.380-386
• Main Authors: Guo, Chao, Cao, Qi, Chen, Bokun, Yang, Siyu, Qian, Yu
• Format: Article
• Language: English
• Subjects: Coal gasification wastewater; Solvent mixture; Synergistic extraction process; Treatment cost
• ISSN: 0959-6526; 1879-1786
• DOI: 10.1016/j.jclepro.2018.11.227

Due to the limitation of the existing solvents, the phenols recovery process cannot control phenols concentration to less than 300 mg/L. Therefore, this study presented a synergistic phenols extraction process by using optimal design solvent mixture. The solvent mixture was proposed with the volume ratio of methyl isobutyl ketone (MIBK) to n-pentanol 6:4. The synergistic extraction process was simulated to acquire the parameters with treatment 130 t/h coal gasification wastewater. The removal efficiencies of phenols and treatment costs for the synergistic extraction process had been addressed. The removal efficiency of total phenols can reach to 97.0% after two-stage extraction, and the concentration of total phenols can be decreased from 6273 mg/L to 190 mg/L. Compared with single solvent MIBK, the reduction of phenols emissions is 47.2% by proposed solvent mixture. The operation cost and income of crude phenols showed that synergistic extraction process realized profit about 3.35 CNY/t. Given the removal efficiencies and treatment costs, the solvent mixture (60% MIBK, 40% n-pentanol) is very promising for phenols removal. •The solvent mixture was proposed with the volume ratio of MIBK to n-pentanol 6:4.•Process simulations and treatment costs for the synergistic extraction process had been addressed.•The reduction of phenols emissions is 47.2% by novel process compared to the process with MIBK.•Synergistic extraction process has good economic feasibility.