Process for making a feed of normal butanol, iso-butanol and 2-alkyl alkanol

A process for the production of normal butanol, iso-butanol and 2-alkyl alkanol the process comprising:

• (a) Hydrogenating a feed comprising normal butyraldehyde, iso-butyraldehyde and 2-alkyl alkenal to form a crude product stream comprising normal butanol, iso butanol, 2-alkyl alkanol, unreacted normal butyraldehyde, unreacted iso-butyraldehyde and one or more of unreacted 2-alkyl alkenal, 2-alkyl alkanal or 2-alkyl alkenol;
• (b) Separating the crude product stream to produce:
• a mixed butanol stream having higher concentrations of normal butanol, iso-butanol, unreacted normal butyraldehyde and unreacted iso-butyraldehyde than the crude product stream;
• and a crude 2-alkyl alkanol stream having higher concentrations of 2-alkyl alkanol and the one or more of unreacted 2-alkyl alkenal, 2-alkyl alkanal or 2-alkyl alkenol than the crude product stream;
• (c) Separating the mixed butanol stream to produce:
• a refined normal butanol stream having a higher concentration of normal butanol than the mixed butanol stream;
• and a crude iso-butanol stream comprising at least some of the unreacted iso-butyraldehyde and having a higher concentration of iso-butanol than the mixed butanol stream;
• (d) Feeding the crude iso-butanol stream to a first polishing hydrogenation reactor wherein at least some of the unreacted iso-butyraldehyde is converted to iso-butanol to produce a polished iso-butanol stream;
• (e) Separating the polished iso-butanol stream to produce:
• a refined iso-butanol stream having a higher concentration of iso-butanol than the polished iso-butanol stream;
• and a light waste stream;
• (f) Separating the crude 2-alkyl alkanol stream to produce:
• an intermediate 2-alkyl alkanol stream having higher concentrations of 2-alkyl alkanol and the one or more of unreacted 2-alkyl alkenal, 2-alkyl alkanal or 2-alkyl alkenol than the crude 2-alkyl alkanol stream;
• and a heavy waste stream;
• (g) Feeding the intermediate 2-alkyl alkanol stream to a second polishing hydrogenation reactor wherein at least some of the one or more of unreacted 2-alkyl alkenal, 2-alkyl alkanal or 2-alkyl alkenol is converted to 2-alkyl alkanol to produce a polished 2-alkyl alkanol stream having a higher concentration of 2-alkyl alkanol than the intermediate 2-alkyl alkanol stream;
• and
• (h) Separating the polished 2-alkyl alkanol stream to produce:
• a refined 2-alkyl alkanol stream having a higher concentration of 2-alkyl alkanol than the polished 2-alkyl alkanol stream;
• and an intermediate waste stream.