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