Abstract: A control system for regulating the reaction zone temperature in a process for the acid-catalyzed alkylation of an isoparaffin with a mixed olefinic feed stream. Composition characteristics of the liquid alkylate product and the olefinic feed stream are determined, and representative output signals transmitted to computer/comparator means which generates a computer output signal in response to, and as a function thereof. The computer output signal is employed to adjust the reaction zone temperature, for a given olefinic feed composition, in order to maximize the octane rating of the liquid alkylate product. The control system effects rapid compensation for feed composition changes which would otherwise adversely affect the product octane rating.

Abstract: A system for controlling the hydrogen/hydrocarbon mole ratio in a continuous hydrocarbon conversion process in which hydrogen is consumed in a catalytic reaction zone. Applicable to processes in which the reaction zone effluent is separated to provide a liquid product phase and a hydrogen-rich vaporous phase, a portion of the latter being recycled to the catalytic reaction zone, the control system affords improved overall operation in addition to increased catalyst activity and stability. Analyzers are utilized to monitor composition characteristics of the charge stock and liquid product, and the hydrogen concentration of the vaporous phase introduced into the reaction zone. Representative process output signals are transmitted to comparator/computer means which compares the rate of change of the composition characteristics and the hydrogen concentration, and generates additional, comparator output signals which are utilized within the control system for regulating the hydrogen/hydrocarbon mole ratio.

Abstract: The specific disclosure is directed to a catalytic cracking model wherein the reactant and product species are lumped according to molecular type and boiling range. The specific invariant lumping scheme includes paraffins, naphthenes, aromatic rings, and aromatic substituent groups.

Abstract: A method and apparatus for the separation of a normally liquid stream comprising low, high and intermediate volatility components by distilling the feed stream in a distillation zone, removing a vaporous overhead stream comprising the high volatility components together with some of the intermediate volatility component, removing from a central portion of the zone a vaporous side stream consisting essentially of the intermediate volatility component, the rate of removal of the intermediate volatility component being controlled by the liquid level of the intermediate volatility component condensed from the overhead stream and contained in a reservoir.

Abstract: A control system and method for regulating the reaction zone temperature in a process for the acid-catalyzed alkylation of an isoparaffin with an olefinic feed stream containing mixed olefins. The reaction zone temperature is adjusted to obtain the optimum for a given feed composition, in order to maximize the octane rating of the ultimate normally liquid alkylate product. The control system effects rapid compensation for continuing changes in feed composition which, at a fixed reaction zone temperature, otherwise adversely affect the octane rating.