Encapsulation Of Metal Phthalocyanines In MCM-41 And Their Catalytic Proerties

Metal phthalocyanines and their derivatives are highly stable and versatile aromatic macrocyclic compounds; they have a similar molecular structure to porphyrin and have attracted much attention for many decades. However, metallophthalocyanines and most of the metal polymeric phthalocyanines are insoluble in common organic solvents, this limits the scope of application. Thus, the solubility can be improved by introducing different kinds of solubility-enhancing substituents, and the polymer can be restrained by dispersing in solvents or loading in molecular sieves. By loading the metal phthalocyanines in appropriate molecular sieves, the catalysts have advantages of high catalytic activity and easy separation and recycling. Because of well-defined mesopores, distributed evenly aperture, extremely high surface area and good thermal stability, MCM-41 has been the focus of much research interest in heterogeneous catalysis area.In this paper, cobalt(copper) tetra(hydroxyethylthio)phthalocyanines and series of tetracarboxylic cobalt(iron,copper) phthalocyanines were synthesized by liquid and solid method respectively. Then the complexes were encapsulated into MCM-41 by immersion method. And the iron tetrasulfophthalocyanine was encapsulated into MCM-41 by immersion method and hydrothermal-extraction respectively. The catalysts were characterized and their catalytic performances were investigated. The main research results are as follows:(1) Co(â…¡), Cu(â…¡) phthalocyanines bearing a hydroxyethylthio substituent on each benzo group were prepared from 4-(hydroxyethylthio)phthalonitrile and the corresponding divalent metal salts; Series of tetracarboxylic metal phthalocyanines were synthesized from trimellitic anhydride, uera, metal salts and ammonium molybdate. And they were characterized by 1H NMR, FT-IR spectra and UV-Vis spectra.(2) Metal tetra(hydroxyethylthio)phthalocyanines and tetracarboxylic metal phthalocy-anines were encapsulated into MCM-41 by immersion method, and iron tetrasulfophthalocy-anine was encapsulated into MCM-41 by immersion and hydrothermal-extraction method respectively. The amounts of metal phthalocyanines encapsulated inside the pore of MCM-41 were measured by spectrophotometry standard curve and inductively coupled plasma-atomic emission spectrometry(ICP) respectively. The properties of the catalysts were characterized by FT-IR spectra, UV-Vis diffuse reflectance spectra, XRD, TGA and N2 adsorption. (3) The reaction of phenol hydroxylation was conducted using metal phthalocyanine/ MCM-41 as catalyst,30 wt% H2O2 as oxidation, and products were analysed by HPLC. Studied the influences of various factors on the reaction, such as temperature, time, amounts of hydrogen peroxide and catalyst, the initial concentration of phenol, et al. We compared the structure and catalytic properties of the tetrasulfonated iron phthalocyanine/MCM-41 synthetised by immersion method and hydrothermal synthesis method. The results showed that the catalyst synthetized by immersion method showed better performance on catalytic activity and selectivity; By studying the effect of different metal(iron, cobalt, copper) in metal tetracarboxyphthalocyanine/MCM-41, the results showed that iron tetracarboxyphthalocyani-ne/MCM-41 was the best catalyst in hydroxylation of phenol.