Control of catalytic hydrotreating selectivity with ammonia. [Quarterly] report, July 1, 1993--September 30, 1993

For the model reaction studied, the addition of NH{sub 3} increases the selectivity towards ring hydrogenation (generally desired) and away from dealkylation (generally undesired). However the overall reaction rate for a fixed temperature drops substantially. Selectivity is the greatest at the lowest temperatures. The effect of NH{sub 3} is less than proportional to its partial pressure. The results obtained here suggest how operating conditions might be adjusted to obtain an optimum amongst desired reaction rates, conversion and selectivity, in the presence of small concentrations of NH{sub 3} or other bases.