(31b) Promising Chemical Treatment Approach for 1,3-Butadiene Fouling

At Braskem’s Camaçari site, in a Nippon Zeon design plant, 1,3-butadiene is produced by extractive distillation with dimethylformamide (DMF) used as solvent. Since longer campaigns have been desired, the treatment of the extraction section has become more challenging, especially due to its historical issues with widespread polymerization at the bottoms of extractive towers.

This paper recaps the general mechanisms involving fouling on butadiene extraction and how SUEZ and Braskem are working together to control severe fouling on the system with a promising inhibition chemical program currently used. Then some positive preliminaries results will be shown.

This process is featured by high temperature at the bottoms of the extractive distillation towers. Hence, this environment is severe enough to easily foul rubber and sheet forms of polybutadiene on economizers, reboilers and on tower’s chimney trays. OH-TEMPO chemical additive is commonly used in this system with the function of inhibit this phenomenon, but for large runs purposes this approach may be not enough. To improve inhibition efficiency, a new synergic blend of OH-TEMPO with a specific antioxidant has been used covering critical areas of the process and responding better than the previous chemical used.