The one-step conversion of ethanol to 1,3-butadiene was performed using talc containing Zn (talc/Zn) as a catalyst. The influence of the MgO and Zn in the talc on the formation rate and selectivity for 1,3-butadiene were investigated. MgO as a catalyst afforded 1,3-butadiene with a selectivity that was nearly the same as talc/Zn at ∼40% ethanol conversion at 673 K, although the rate of 1,3-butadiene formation over MgO was about 40 times lower than that over the talc/Zn. The introduced Zn cations were located in octahedral sites in place of Mg cations in the talc lattice. The Zn cations accelerated the rate of CHCHO formation from ethanol, resulting in an increase in the rate of 1,3-butadiene formation. However, the rate of CHCHO consumption to form crotonaldehyde was not influenced by Zn, although the distribution of crotonaldehyde was decreased with increasing Zn concentrations. X-ray photoelectron spectra of talc/Zn showed that the O binding energy was increased by increasing the concentration of Zn, while those of both Mg and Si were hardly influenced. DFT calculations were used to estimate the atomic charges on the O, Mg, Si, and Zn atoms when an atom of Zn per unit cell of talc was introduced into an octahedral site. On the basis of the results for the conversion of ethanol into 1,3-butadiene and the corresponding DFT calculations, the roles of the O, Zn, Mg, and Si atoms in the talc catalyst for the formation of 1,3-butadiene from ethanol were discussed.

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1,3-Butadiene is produced as a by-product during ethylene production from steam crackers. Increasing demand for sustainable chemicals has driven the search for substitute petrochemicals from renewable biomassderived chemical resources. 1,3-Butadiene is an important commodity chemical and an alternative route for its production, from ethanol, was developed about a hundred years ago. In the current climate, the development of a new high-performance catalyst for the bio-based synthesis of 1,3-butadiene is an important challenge. This paper reviews our recent studies into the synthesis of 1,3-butadiene from ethanol using MgO alone, and Zn-containing talc (Zn-Talc) that has not previously been used as a catalyst for this reaction. In particular, we focus on catalysis by MgO and the role that Zn 2 in the Zn-Talc catalyst plays in the selective production of 1,3-butadiene. The reaction mechanism for the formation of 1,3-butadiene from ethanol over MgO, and the effect of Zn 2 on the rate of ethanol conversion are discussed.