Pilot plant study for management of toxic solid waste collected in landfill of spent lubricant oil refinery by conversion into zeolite packed bed via continuous extrusion and fusion techniques

The pilot plant extrusion was successfully utilized to manage a clay based solid waste deposited in the landfill of spent oil refinery through the conversion into the rod-like zeolite with LTA (Linde Type A) structure. The research was designed in combination with fusion, and hydrothermal processes to produce a packed bed with appropriate cation exchange capacity (CEC). However, the conversion of waste into the proper zeolite structure was the challenge of study due to lack of aluminum. To address this issue, boehmite, and sodium hydroxide were added to solid waste for compensation of aluminum lack before extrusion. The extrudates were further consolidated by fusion at 800 degrees C, and then were converted into zeolite LTA by control of aging, and reaction periods in the hydrothermal step. The crystallinity, microstructure, and textural characteristics of waste, and fabricated rods were studied to examine the capability of process. The results revealed that the rod fabricated through the short aging period, 3 h, and longer reaction time, 9 h, represents the minimal CEC due to the recrystallization of hydroxysodalite. Although the textural characteristics of zeolites were found to be slightly affected by extrusion, the aging, and reaction periods of 9, and 6 h are beneficial to produce a packed bed with proper CEC, 214 mg g(-1), demonstrating the potential of innovated technique. (C) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.