摘要
制备了过渡金属修饰的磷钨酸盐(M_xH_(3-2x)PW_(12)O_(40),M=Co,Cu,Zn,Ni)催化剂,用BET,ICP,XRD,FTIR,NH_3-TPD等技术对其性能进行了表征,并考察了该系列催化剂在芳香类化合物的Friedel-Crafts乙酰化反应中的活性。实验结果表明,多孔性M_xH_(3-2x)PW_(12)O_(40)保持了磷钨酸的Keggin结构和酸强度,酸量明显大于磷钨酸。在茴香醚乙酰化反应中,M_xH_(3-2x)PW_(12)O_(40)(除Co_(1.5)PW_(12)O_(40)外)的催化活性和选择性明显高于磷钨酸和Cs_(2.5)H_(0.5)PW_(12)O_(40),其中Co_(0.5)H_2PW_(12)O_(40)的催化活性最高。以Co_(0.5)H_2PW_(12)O_(40)为催化剂合成对甲氧基苯乙酮(p-MOPA)时,P-MOPA收率和选择性分别达到84.36%和96.78%。Co_(0.5)H_2PW_(12)O_(40)用于苯衍生物、噻吩及其衍生物的乙酰化反应时电呈现较好的催化活性和选择性,其中,2-乙酰噻吩的收率和选择性分别达到86.93%和99%以上。
A series of transition metal-modified phosphotungstate catalysts （MxH3-2xPW12O40, M = Co,Cu,Zn,Ni） were prepared and characterized by means of BET, ICP,XRD,FTIR and NH3-TPD. Activities of the MxH3-2xPW12O40 catalysts in Friedel-Crafts acetylations of aromatic compounds were investigated. The experimental results showed that the porous MxH3.2x PW12O40 catalysts kept the primary Keggin structure and the acid strength of phosphotungstic acid H3PW12O40, but their acid amounts were more than that of H3PW12O40. Compared with H3PW12O40 and Cs2.5 H0.5 PW12 O40 catalysts, both activities and selectivities of the MxH3-2xPW12O40 catalysts （ except Co1.5 PW12O40） in acetylation of anisole were high, in which Coo. 5 HzPW12O40 catalyst was best, and yield and selectivity of product p-methoxyacetophenone （p-MOPA） could be 84.36% and 96.78%, respectively. Both activity and selectivity of the Co0.5H2PW12O40 catalyst were high when it was used in acetylations of benzene derivatives, thiophene and its derivatives. For example, yield and selectivity of 2-acetyl thiophene could reach 86.93% and more than 99%, respectively.
出处
《石油化工》
CAS
CSCD
北大核心
2010年第12期1354-1359,共6页
Petrochemical Technology
