The CO and H2 components of the first stream are reacted under high pressures and, optionally, in the presence of {HEAD ~ a catalyst}, such as a copper and zinc containing catalyst, to form methanol and {TAIL ~ higher alcohols} 
The CO and H2 components of the first stream are reacted under high pressures and , optionally , in the presence of { HEAD ~ a catalyst } , such as a copper and zinc containing catalyst , to form methanol and { TAIL ~ higher alcohols }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL