Metallophosphates

The structures of many other metal phosphates have been reported in which the metal is in mixed or non-tetrahedral conformation, but without much information on the porosity or thermal stability. The vanadyl phosphates reported by Schindler and Baur, for example, can be considered to be built up from planar V509(P04)4 units that share phosphate tetrahedra. These have the same topology as 4MRs, so that analogue structures that are similar to zeolite structures that are made up completely of 4MRs such as sodalite and Rho can be prepared. 

---

Similarly, other families of metallophosphates oxynitrides have been studied with catalytic objectives in different M-P-O-N systems (M = Ga, AlGa, AlCr, In, Ti, Zr,. ..) (235). 

Early to mid-1990s Metallophosphates Mesoporous molecular sieves Octahedral-tetrahedral frameworks... 

The first part of the book documents the history, structure, chemistry, formulation and characterizations of zeolites in Chapters 1-4. The past 60 years have seen a progression in molecular sieve materials from aluminosilicate zeolites to micro-porous silica polymorphs, microporous aluminophosphate-based polymorphs, metallosihcate and metallophosphate compositions, octahedral-tetrahedral frameworks, mesoporous molecular sieves and, most recently, hybrid metal organic frameworks (MOFs). 

The synthesis and properties of another group of acidic metallophosphates, having the general formula Al F Fe has been discussed by Petrakis et al. (1995). Products containing at least 15% phosphorus were found to be X-ray amorphous, mesoporous solids, but at a lower P content there was evidence of phase separation of the Fe and Al. 

Complexes of chlorobenzenes with iron (cyclopentadienyl)hexafluorophosphate have useful reactivities, for example, in cyclization. The complex (28.7) is cyciized with hydrazine to a dihydrocinnoline complex the metallophosphate is removed and the ring is aromatized by sodamide. 

Essential facts and figures on the synthesis of crystalline microporous materials can be found in the textbooks by Breck [15], Barrer [16] and Szostak [8], and also within previous volumes on zeolite science and technology published in collaboration with the International Zeolite Association (IZA) [ 17,18], These sources contain (besides much other useful background material) chapters on the synthesis of zeolites, metallophosphates and other porous framework structures. 

Broensted and Lewis acid sites in crystalline phosphates, silicates and in gels with moleculeu sieve properties were studied by IR-spectroscopy. Two types of bridged hydroxyls were fovmd in SAPO-5 which were accessible to adsorbed molecules and were able to interact with ethylene. Lewis sites in metallophosphates, zirconosilicate and in Ti-containing silica gel were observed which did not interact with weak bases (CO, hydrogen) but formed strong complexes with acetonitrile. They were supposed to be framework metal ions in tetrahedral coordination. 

I. Other Systems/X-Ray Amorphous Metallophosphate Oxynitrides VI. Conclusion References... 

Investigations of the potential of new molecular sieve structures, e.g., metallophosphates, titanoaluminophosphates (TAPOs) [24], ferroaltiminophosphates (FAPOs) [25], etc., as the corresponding altuninophosphate structures sometimes show the presence of sites with a coordination virtually higher than tetrahedral [26]. 

---