Synthesis of 2-Methylpyrazine Using Crude Glycerol over Zn-Cr-O Catalyst: A Value Addition Process for the Utilization of Biodiesel By-Product

Mixed oxides of ZnO and Cr2O3 with varied mole ratios were synthesized, characterized, and evaluated for the dehydrocyclization of crude glycerol for the production of 2-methylpyrazine (2-MP). The Zn-Cr-O composition was optimized using the bulk and surface properties of the catalysts rationalized by BET-SA, XRD, XPS, H2-TPR, O2 pulse chemisorption, and Raman spectroscopic techniques to achieve a high rate of 2-MP

Zn-Modified CuCr₂O₄ as Stable and Active Catalyst for the Synthesis of 2,6-Dimethylpyrazine: Valorization of Crude Glycerol Obtained from a Biodiesel Plant

Modified CuCr₂O₄ catalysts were investigated for vapor phase conversion of crude glycerol and 1,2-propanediamine (1,2-PDA) to synthesize 2,6-dimethylpyrazine (2,6-DMP). The addition of Zn not only enhanced the activity of CuCr₂O₄ but also improved the stability of the catalyst. The introduction of Zn into the CuCr₂O₄ matrix increased the copper metallic surface area of the catalyst. The rate of 2,6-DMP is found to be dependent on the Cu metal surface area. Diffuse reflectance infrared Fourier transform spectroscopic data revealed that a high fraction of Lewis-acid–base pair sites are responsible for the selective formation of 2,6-DMP. A direct correlation between 2,6-DMP rate and the surface Cu is established