Activated petroleum waste sludge biochar for efficient catalytic ozonation of refinery wastewater

Chunmao Chen; Xin Yan; YingYing Xu; Brandon A Yoza; Xin Wang; Yue Kou; Huangfan Ye; Qinghong Wang; Qing X Li

doi:10.1016/j.scitotenv.2018.10.131

Activated petroleum waste sludge biochar for efficient catalytic ozonation of refinery wastewater

Sci Total Environ. 2019 Feb 15;651(Pt 2):2631-2640. doi: 10.1016/j.scitotenv.2018.10.131. Epub 2018 Oct 11.

Authors

Chunmao Chen¹, Xin Yan¹, YingYing Xu¹, Brandon A Yoza², Xin Wang¹, Yue Kou¹, Huangfan Ye¹, Qinghong Wang³, Qing X Li⁴

Affiliations

¹ State Key Laboratory of Heavy Oil Processing, State Key Laboratory of Petroleum Pollution Control, China University of Petroleum, Beijing 102249, China.
² Hawaii Natural Energy Institute, University of Hawaii at Manoa, Honolulu, HI 96822, USA.
³ State Key Laboratory of Heavy Oil Processing, State Key Laboratory of Petroleum Pollution Control, China University of Petroleum, Beijing 102249, China. Electronic address: wangqhqh@163.com.
⁴ Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, HI 96822, USA. Electronic address: qingl@hawaii.edu.

PMID: 30463118
DOI: 10.1016/j.scitotenv.2018.10.131

Abstract

Large quantities of hazardous activated petroleum waste sludge and wastewaters are generated from petroleum refining. The present disposal of the sludge via incineration or landfill may cause secondary pollution as well as additional costs. Treatment of petroleum refinery wastewater (PRW) by catalytic ozonation process (COP) remains a great challenge of developing low-cost and high-efficiency catalysts. Use of waste sludge derived biochar as catalysts in COP of PRW not only solves the solid wastes and wastewaters problems but also improves profitability. The elements of carbon (C), silicon (Si) and metals originally found in activated petroleum waste sludge contribute to the formation of active sites during pyrolysis. The biochar contains functional C groups, SiO structures, and metallic oxides that promote oxidation through the formation of hydroxyl radicals (OHs) mineralizing petroleum contaminants. Catalytic ozonation of PRW using this sludge biochar (SBC) doubles the total organic carbon removal (53.5%) relative to single ozonation (26.9%). Oxygen (Ox)-, nitrogen (NOx)- and sulfur (OxS)-containing contaminants were decreased by 33.4% (989 vs 659), 58.2% (912 vs 384) and 12.5% (384 vs 336). The present study shows the potential of a "wastes-treat-wastes" process for wastewater treatment.

Keywords: Biochar; Catalytic ozonation; Petroleum; Waste activated sludge; Wastes-treat-wastes; Wastewater.