Preparation of carbonaceous adsorption composite with refinery sludge for butyl xanthate and diethyldithiocarbamate removal in flotation wastewater

In order to utilize refinery sludge with high value added, pyrolysis method with refinery sludge for preparing a carbonaceous adsorption composite was proposed in this study. The prepared carbonaceous adsorption composite was characterized by the removal efficiency of butyl xanthate and diethyldithiocarbamate in synthetic flotation wastewater. X-ray diffraction, scanning electron microscope with energy-dispersive spectroscopy, and specific surface area analysis were used to explore the properties of the raw materials and production. The results showed that optimum preparation conditions were the temperature of 800 °C, heating rate of 8 °C/min, N2 flow of 140 mL/min for 45 min. With the best preparation conditions, the removal efficiency of butyl xanthate and diethyldithiocarbamate was 95.73% and 88.07%, respectively. The carbonaceous adsorption composite was mainly composed of fixed carbon of 46.96% and ash of 48.42%. The fixed carbon formed the porous skeleton structure of composite, while the ash was embedded in the skeleton in the form of anorthite, kyanite, and pyrite. The specific surface area was 204 m2/g, and the average pore diameter was 6.83 nm. It is proved feasible to prepare carbonaceous adsorption composite with refinery sludge for the removal of butyl xanthate and diethyldithiocarbamate in synthetic flotation wastewater.