Influence of method of preparation of Co-Cu/MgO catalyst on dehydrogenation/dehydration reaction pathway of 1, 4-butanediol

Co-Cu/MgO catalyst was prepared by two different methods; one involving generation of Cu and Mg mixed carbonate by coprecipitation followed by mixing it with Co carbonate (Catalyst-1) and the second method involving coprecipitation of all the nitrate salts to get the mixed carbonate (Catalyst-2). Contacting 1,4-butanediol on Catalyst-1 under vapor phase yielded γ-butyrolactone via dehydrogenation, whereas, Catalyst-2 yielded tetrahydrofuran via dehydration. Higher Cu dispersion obtained by N2O pulse chemisorption due to smaller particle size in Catalyst-1 is found to be responsible for the lactonization activity. The presence of strong acid sites, as determined by NH3 TPD, in Catalyst-2 leads to tetrahydrofuran formation by dehydration of 1,4-butanediol.

Graphical AbstractMethod of preparation of Co-Cu/MgO catalyst has profound influence on the selectivity in the reaction pathway of 1,4-butanediol transformation.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch Highlights► Mode of addition of Co to Cu/MgO is very crucial in deciding the catalytic activity. ► In the case of Catalyst-1, highly acid sites outplay Cu dispersion favoring dehydration. ► In the case of Catalyst-2, higher Cu dispersion favors dehydrogenation pathway.