Ag-Cu Bimetallic Nanoparticles Prepared by Microemulsion Method as Catalyst for Epoxidation of Styrene

Table 4

Styrene epoxidation at different ratio of Ag/Cu supported on γ-Al₂O₃^a.

Entry	Ag/Cu molar ratio	Conversion (%)^b	Selectivity (%)^b
			Epoxide	Benzaldehyde	Phenyl acetaldehyde
I	No catalyst	37.4	None	>99.9	c
II	γ-Al2O3	42.1	49.6	46.6	3.8
1	Ag : Cu = 1 : 0/γ-Al2O3	89.7	65.6	34.4	c
2	Ag : Cu = 3 : 1/γ-Al2O3	93.5	76.6	23.4	c
3	Ag : Cu = 1 : 1/γ-Al2O3	94.6	66.9	33.1	c
4	Ag : Cu = 1 : 3/γ-Al2O3	87.5	62.0	38.0	c
5	Ag : Cu = 0 : 1/γ-Al2O3	83.7	20.4	79.6	c

^aReaction conditions: Ag-Cu/γ-Al₂O₃ catalyst 5 mg, CH₃CN 2 mL, styrene 0.5 mmol, TBHP 1.5 mmol, 82°C, 6 h.
^bDetermined by GC; use bromobenzene as internal standard, the correction factor is 1.27.
^cProduct not detected.