Hydroamination of n-butanol on Cu-containing anion-modified catalysts

Abstract

The purpose of the work is to establish the relationship between the composition of new Cu-containing anion-modified compositions and their catalytic potential in the synthesis of dibutylamine, which is an important intermediate for the production of such significant products as medicines, insecticides, vulcanization accelerators for rubber compounds, multifunctional corrosion inhibitors, etc. Composite materials were prepared by thermal decomposition of a copper-ammonia-carbonate solution in the presence of chromate, molybdate, aluminum tungstate, aluminum metahydroxide, and lanthanum carbonate salts. The active state of the new catalysts was formed under the conditions of low-temperature heat treatment (2500C) and reduction (2400C), which ensure incomplete removal of modifying OH– and СО32– anions. The study of the catalytic efficiency of new samples in the process of vapor-phase hydroamination of n-butanol was carried out in a flow reactor at the n-butanol:ammonia:hydrogen molar ratio equal to 1.0:2.0:6.0, an alcohol load of 0.4 h–1 and temperatures of 200–2400C. Among the catalysts tested, the sample whose precursor was a mixed "compound" salt hydroxocarbonate copper-aluminum chromate showed the highest performance as follows: alcohol conversion and selectivity to the target dibutylamine of 86.3% and 82.7%, respectively (at 2200C). The least active was the sample, the precursor of which was a mixed "compound" salt hydroxocarbonate copper-lanthanum carbonate. Factors that can affect the catalytic efficiency of new materials were analyzed.