HF alkylation process and reaction temperature control system

A control system for regulating the reaction zone temperature in a process for the acid-catalyzed reaction of an isoparaffin with an olefinic feed stream containing mixed olefins. Hydrocarbon analyzers produce process output signals which are representative of composition characteristics of the fresh olefinic feed stream and the liquid alkylate product. These process output signals are transmitted to computer/comparator means which develops an output signal as a function thereof. The computer output signal is employed to adjust the reaction zone temperature to obtain the optimum consistent with a given feed composition and desired alkylate product quality. The control system rapidly compensates for continuing changes in feed composition which, at a fixed reaction zone temperature, would otherwise adversely affect the alkylate product quality.