Potassium modified NaY: A selective and durable catalyst for dehydration of lactic acid to acrylic acid

Potassium modification significantly improved the selectivity and durability of NaY zeolites during lactic acid dehydration reaction. The selectivity of 2.8K/NaY zeolites improved from 14.8% to 50.0% over NaY catalyst. Adding potassium also prolonged catalyst life. After 22 h the acrylic acid selectivity of NaY zeolites reduced to less than 10.0% while that of 3.5K/NaY retained 35.6%. Characterizations with NH3-TPD, CO2-TPD, N2 adsorption and thermal analysis techniques revealed that the enhancement of catalytic performances could be attributed to the tuned acidity/basicity and the potassium electronic promoter effect.