Patent ID: 7074979

Claim:
A process for forming light olefins, the process comprising the steps of: (a) providing a methanol feedstock from a tanker which previously carried a non-methanol material or which was designed to carry a non-methanol material and which comprises a blanketing system for delivering medium to one or more holds, wherein the methanol has at least one contaminant selected from the group consisting of: soot, rust, leachable metals, SO x , carbonic acid, and C 5 -hydrocarbons; (b) vaporizing at least a portion of the feedstock to form a vaporized feed stream, wherein the vaporized feed stream comprises vaporized methanol and at least a portion of the contaminant that was present in the feedstock; and (c) contacting the vaporized methanol with a catalyst in a reactor under conditions effective to convert at least a portion of the vaporized methanol to tile light olefins.