Glycerin Acetal Reaction In The Process Of Hydrogenation Product Separation Research

Polyhydroxy compounds such as ethylene glycol (EG) and propylene glycol areimportant chemical intermediates widely used in producing polyester, surfactant,lubricant, and adhesives. EG and PG are difficult and expensive to recover fromaqueous solution because of its high boiling point and affinity with water, Recently,reactive distillation (RD) has gained attention for equilibrium reactions and for thoseseparations that are difficult to conduct via conventional means. The advantages ofRD include simplicity, reduced operating costs, and improving product purity inreversible reactions.The objective of the research was to investigate catalytic activity of ion-exchangeresins in acetalization of ethylene glycol with acetaldehyde. Three differentcommercial resins (Resin732, D072, NCK-9) were used in the experimental research.The impacts of reaction variables, such as temperature, reaction time, catalyst loadingand feedstock composition, on the conversion of EG and PG were measured.The results indicate that D072type cationic exchange resin catalyst exhibitedexcellent catalytic activity for aldolization comparable to732and NCK-9, Underoptimal condition,85%conversion of PG in aqueous solution was achieved within180min of reaction. The kinetics of acetalization followed the second-order reactionkinetics, and the apparent activation energy, was found to be17.06kJ/mol, and thereaction rate constant, was found to be29.68min-1. about70.1%ehthylene glycolconversion was achieved in3hours of reaction time. The resin catalyst was found todeactivate over time and the catalyst life was investigated by testing the spent resincatalyst repeatedly in batch operation. Results indicated that after5cycles of test,ethylene glycol conversion was dropped from70.1to42.7%. Furthermore, thereaction kinetics of ethylene glycol acetalization was studied. reaction followed thesecond-order reaction kinetics, and the apparent activation energy, was found to be46.92kJ/mol，and the reaction rate constant was found to be27.45min-1.