Converting alcohols to hydrocarbons

A method for converting reactant materials selected from the group consisting of lower alcohols, ether derivatives thereof, oxygenates of synthesis gas and any one or a combination thereof which comprises,

• passing the reactant material in vaporous, liquid or a mixture thereof condition upwardly through a fluid bed of zeolite catalyst particles characterized as providing a silica/alumina ratio of at least 12, a pore opening of at least 5 Angstroms and a Constraint Index within the range of 1 to 12 at a temperature constrained within the range of about 600.degree. F. to about 775.degree. F. under pressure and space velocity conditions selected to achieve at least 95% conversion of a methanol feed to hydrocarbon products including gasoline boiling range products,
• said temperature constrained limits achieved at least in part by a plurality of heat exchange tubes immersed in a fluid bed of said catalyst and providing high pressure steam as a result of said heat exchange, said reactant restricted in gasified bubble growth to less than 24 inch hydraulic diameter during contact with said bed of fluid catalyst particles by a plurality of vertical open ended baffle tubes slotted in the wall thereof for flow of catalyst and gasiform reactant material therethrough adjacently positioned in combination with said heat exchange tubes,
• said reactant conversion exotherm further constrained by maintaining from 5 to 20% by weight of coke-like material on the zeolite catalyst in the reaction zone,
• maintaining a high rate of catalyst circulation from a dispersed catalyst phase above said fluid catalyst bed to a bottom portion of said bed following separation of reaction product from said catalyst passing into said dispersed phase, and recovering products of said conversion operation comprising gasoline boiling range hydrocarbons.