K_2CO_3/NaY催化苯酚与碳酸二乙酯合成苯乙醚

以负载型固体碱K2CO3/NaY为催化剂、碳酸二乙酯(DEC)为乙基化试剂,催化苯酚与DEC进行液相乙基化反应合成苯乙醚。采用Hammett指示剂法和X射线衍射技术对K2CO3/NaY催化剂进行表征。实验结果表明,催化剂上的弱碱中心(7.2

Synthesis of Phenetole by Ethylation of Phenol with Diethyl Carbonate over K2CO3/NaY Catalyst

Synthesis of phenetole by ethylation of phenol with diethyl carbonate(DEC) as an alkylating agent in liquid phase was studied and K2CO3/NaY was used as catalyst.The solid base catalyst was characterized by means of Hammett indicator method and XRD.The weak basic sites(7.2< H-<9.3,H-was designated as basicity)were active in the ethylation.The amount of basic sites increased with increasing of K2CO3 loading amount.When K2CO3 loading amount(mass fraction based on mass of K2CO3/NaY catalyst) was 25%,the activity of the catalyst was the highest.Further increase of K2CO3 loading amount contrarily caused the decrease of basic sites due to blockage of the catalyst pores.Effects of reaction temperature,catalyst dosage,mole ratio of reactants and reaction time on catalytic activity were also studied.Under optimal reaction conditions:reaction temperature 150 ℃,catalyst mass fraction(based on total mass of the system) 4%,n(DEC):n(phenol) 1.5,reaction time 150 min,conversion of phenol and selectivity to phenetole were 99.5% and 97.8%,respectively.