Abstract: In a process for producing a molecular sieve material, water, at least one source of an oxide of a tetravalent and/or a trivalent element and at least one structure directing agent is mixed in a reactor equipped with a mixer having a Froude number of at least 1, to produce a molecular sieve synthesis mixture having a solids content of at least about 20 wt %. The molecular sieve synthesis mixture is heated in the reactor while agitating the mixture with said mixer to form crystals of said molecular sieve material and the molecular sieve crystals are subsequently recovered from the reactor.