Investigations into the conversion of ethanol to butadiene-1,3 using CuO/$\protect \text{La}_2\protect \text{O}_3$/$\protect \text{ZrO}_2$/$\protect \text{SiO}_2$ catalyst systems

Abstract

Catalyst systems of the Lebedev reaction from oxides of Zn, Zr, La, Cu and silica gel were investigated. The catalysts were characterized by BET, XRF, XRD, TPD-$\text{NH}_3$ and TPR. The parameters of ethanol to butadiene-1,3 process were determined using ethanol, acetaldehyde and water as raw materials without inert diluents. When using a mixture of ethanol and acetaldehyde as a feedstock, the selectivity of the butadiene-1,3 formation exceeds 60% and its productivity is at least $0.32~\text{g}_{\mathrm{BD}}{\cdot } \text{g}_{\mathrm{cat}}^{-1}{\cdot }\text{h}^{-1}$. The average butadiene-1,3 yield was over 34% in 8 h. The stability of the CuO/$\text{La}_2\text{O}_3$/$\text{ZrO}_2$/$\text{SiO}_2$ catalyst was evaluated for 5 cycles of 24 h. When using 96% ethanol, the butadiene-1,3 yield decreased from 25.1% to 13.8% during the full cycle. Oxidation regeneration of the catalyst makes it possible to completely restore its catalytic activity.

Keywords

• Butadiene-1,3
• Ethanol
• Lebedev reaction
• ETB process
• Deactivation
• Supported catalysts