Purification of mercaptans or thiophenes using dividing wall column distillation

A process for separating as a side draw stream a primary mercaptan of 4-16 carbon chain length and optionally thiopene from a feed stream, said feed stream containing a mixture comprising primary, secondary and tertiary mercaptans using a distillation column, the process comprising:

• providing one or more distillation columns with said feed stream, the distillation column having a rectification section, a stripping section, and a feed side section separated from a side draw section by a dividing wall that extends from the rectification section to the stripping section;
• condensing a vapor from the distillation column with a condenser and heating a liquid from the distillation column with a reboiler;
• removing a distillate stream from a top region of the distillation column;
• removing said side draw stream of a primary mercaptan of 4-16 carbon chain length from a side region of the distillation column;
• and
• removing a bottoms stream from a bottom region of the distillation column.