Catalytic Cracking of Heavy Crude Oil over Iron-Based Catalyst Obtained from Galvanic Industry Wastes

Abstract

Sewage sludge from the galvanic industry represents a problem to the environment, due to its high metal content that makes it a hazardous waste and must be treated or disposed of properly. This study aimed to evaluate the sludge from three galvanic industries and determine its possible use as catalysts for the synthesis of materials. Catalyst was obtained from a thermal process based on dried between 100–120 °C and calcination of sludges between 400 to 700 °C. The physical–chemical properties of the catalyst were analyzed by several techniques as physisorption of N2 and chemisorption of CO of the material. Catalytic activity was analyzed by thermogravimetric analysis of a thermo-catalytic decomposition of crude oil. The best conditions for catalyst synthesis were calcination between 400 and 500 °C, the temperature of reduction between 750 and 850 °C for 15 min. The catalytic material had mainly Fe as active phase and the specific surface between 17.68–96.15 m2·g−1, the catalysts promote around 6% more weight-loss of crude oil in the thermal decomposition compared with assays without the catalyst. The results show that the residual sludge of galvanic industries after thermal treatment can be used as catalytic materials due to the easiness of synthesis procedures required, the low E-factor obtained and the recycling of industrial waste promoted.

Keywords

• sludge
• catalytic material
• galvanic industry
• waste valorization