Separation method for dinitrotoluene and mixed acid in a toluene to dinitrotoluene process

US9284257B2 · kind B2 · utility

Assignees

• BASF SE
• Shanghai BASF Polyurethane Company Limited · CN

Inventors

• Yuanshen Dai · Mannheim, DE
• DA-PENG LI · Suzhou, CN
• Pei Jia · Nanhu, CN
• Zhan Cai · Longbeilingcun, CN
• Samuel Neto · Brussels, BE

Key dates

• Filing date: Dec 10, 2013
• Grant date: Mar 15, 2016
• Expiry date: Dec 10, 2033

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C201/16
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Proposed is a separation method in a toluene to dinitrotoluene process, wherein said method with a first process step comprising feeding a toluene comprising first stream (1) and a nitric acid comprising second stream (2) into a first reactor (R1), reacting of the toluene comprising first stream (1) and the nitric acid comprising second stream (2) within the first reactor (R1) to a first reaction mixture (3), said first reaction mixture (3) comprising a first liquid/liquid mixed phase of an acid phase and an organic phase comprising mononitrotoluene, feeding the first reaction mixture (3) into a first separation device (S1), separating the first reaction mixture (3) within the first separation device (S1) into a first forward stream (4) having a flow direction to a second process step and a first backward stream (5) having a flow direction back to the first reactor (R1), said method having a second process step comprising feeding the first forward stream (4) into a second reactor (R2), feeding a nitric acid comprising third stream (6) and a sulfuric acid comprising fourth stream (7) into the second reactor (R2), reacting of the first forward stream (4), the nitric acid comprising t…