The BASF NMP-butadiene extraction process offered by Lummus Technology is the preferred technology for the production of high purity 1,3 butadiene from crude C4 cuts. The process has been successfully applied in more than 30 plants worldwide.
The process utilizes two-stage extractive distillation to recover 1,3 butadiene (>99.7% pure) from mixed C4 feed streams using n-methyl-pyrrolidone (NMP) solvent and conventional distillation technology. Solvent consumption is low because of NMP's high boiling point and stability against hydrolysis and thermal decomposition. As well as being non-toxic and non-carcinogenic, the aqueous mixtures of NMP are non-corrosive, allowing for carbon steel construction and therefore lower investment cost. NMP can be treated by conventional biological wastewater treatment, providing a safe, environmentally sound design.