New Lignosulfonate Catalysts in Chemistry and Technology. Synthesis and Prospects for Application

Modified lignosulfonates were studied as a basis for multifunctional sulfo-cationic catalysts applicable in chemical technology for basic organic and petrochemical synthesis. Using the example of the cyclotrimerization reaction of propanal, it was shown that high catalytic activity is due to the multifunctional nature of the catalyst. It has been established that the catalysts have high thermal stability and retain their activity in water-alcohol environments. In the reactions of isobutene hydration, tert-butyl alcohol dehydration, and alkyl tert-butyl ester synthesis, lignosulfonate systems demonstrate competitiveness compared to traditional sulfo-cations, combining high activity with increased stability. Based on the analysis of water distribution along the reactor height, a strategy for layer-by-layer loading of catalysts was proposed, which made it possible to increase alcohol conversion from 70 to 83% and reduce the load on the rectification system. To increase the service life of catalysts, a modernized technological scheme has been proposed, including a stage of preliminary purification of raw materials from transition metal ions.