Mg_1-xCo_xAl₂O₄ Nano-Catalysts Synthesis and their Potential Applications to Reduce Viscosity with Heavy Oil and Dye Degradation

Abstract:

A novel Mg_1-xCo_xAl₂O₄ (x=0, 0.25, 0.50, 0.75 and 1) nano-catalyst with high viscosity reduction rate of heavy oil and photocatalytic activity for the degradation methylene blue was synthesized by a tartaric acid complexation method. The crystallite size, cell parameter, cell volume and particle size of Mg_1-xCo_xAl₂O₄ catalyst are proportional to the x value, while the specific surface area is inversely proportional to the x value. The effects of different catalyst, catalyst content and water content on viscosity reduction rate of Dongying heavy oil were investigated. When the catalyst content of Mg_0.5Co_0.5Al₂O₄ is 15 wt%, the viscosity reduction rate of heavy oil reaches 89.53%, while water decreases the viscosity reduction rate. The degradation percentage of the Mg_1-xCo_xAl₂O₄ (x=0.5) catalyst for the degradation of methylene blue reached 95.34% when the catalyst dose was 1 g/L, the dye concentration was 15 mg/L and pH was 7. The dye sensitization greatly improved the photocatalytic activity of the MgAl₂O₄ under the combined action of Mg and Co ions. This new experimental phenomenon will help to expand the application range of spinel aluminate in catalysis fields including reduce viscosity with heavy oil and dye removal.

• Periodical: Journal of Nano Research (Volume 90)
• Pages: 101-122
• DOI: https://doi.org/10.4028/p-ch7myU
• Online since: December 2025
• Authors: Shi Qi Xu*, Chang He Huang
• Keywords: Aluminate, Heavy Oil, Mg_1-xCo_xAl₂O₄, Tartaric Acid, Viscosity Reduction

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