Method of synthesizing a molecular sieve of MWW framework type

A method of synthesizing a molecular sieve of MWW framework type, the method comprising the steps of:

• a) preparing a synthesis mixture capable of forming a molecular sieve of MWW framework type, said synthesis mixture comprising water, a silicon source, a source of a trivalent element X, a potassium cation source, a structure directing agent R, a source of another alkali metal cation M, optionally a source of a pentavalent element Z, optionally a source of hydroxide ions, and optionally seed crystals, the synthesis mixture having the following molar ratio composition:
• Si:X2=8 to 18
• H2O:Si=5 to 100
• (M+K+):Si=0.1 to 0.5
• M:K+=1 to 10
• R:Si=0.1 to 1;
• b) heating said synthesis mixture under crystallization conditions for a time sufficient to form crystals of said molecular sieve of MWW framework type, said crystallization conditions including a temperature of from 100° C. to 220° C.;
• and
• c) recovering said crystals of the molecular sieve of MWW framework type from the synthesis mixture.