Abstract: A method and an apparatus for controlling reactant ion concentration within a precipitation vessel to optimize the reactions occurring therein is disclosed. In one important implementation, the reactant controlled comprises halide ion in a reactor during the precipitation and growth of silver halide grains. In this embodiment, the method includes measuring the amount of halide ion within the precipitation vessel; measuring the flow rates of the halide feed stream and the silver feed stream; storing the measured halide ion concentration and measured feed stream flow rates; computing an estimated smoothed halide ion concentration value as a function of the stored measured halide ion concentration and measured feed stream flow rates; and adjustably controlling the amount of halide ion added to the precipitation vessel as a function of this estimated halide ion concentration value.

Abstract: A process to convert propylene to gasoline blending stock products comprises contacting C.sub.2 -C.sub.3 olefins under conversion conditions with an AMS-1B crystalline borosilicate catalyst composition.

Abstract: A process to convert an alkane, such as n-butane, to dehydrogenated and isomerized products comprises contacting such alkane under conversion conditions with an AMS-1B crystalline borosilicate catalyst composition containing an ion or molecule of a catalytically active element, such as a noble metal.