Aluminum phosphate based molecular

The alkylation of toluene with methtmol at 400°C over H-ZSM-5 gave, at 36% conversion, a 69% selectivity for xylene formation, of which 27% was the para isomer. 2 Aluminum phosphate based molecular sieve catalysts such as CoAPO gave a lower conversion but higher selectivities for p-xylene formation. 2 Metallosilicates such as As-silicate having a ZSM-5 structure produced an 82% selectivity for p-xylene at 21% conversion. 

Aluminum Phosphate-Based Molecular Sieves. Although still in the early stages of development, aluminum phosphate-based molecular sieves have shown great promise as a microporous catalyst and an adsorbent material. They were first reported in 1982 with a neutral aluminum phosphate (AlP04)-n framework (15), Si, other metals (such as Be, Mg, Ti, Mn, Cr, Fe, Co, and Zn), and other elements (such as Li, B, Ga, Ge, and As) have subsequently been incorporated into the AIPO4 framework these substitutions have allowed additional applications for the catalyst. Some of the applications reported are catalytic dewaxing, hydrocracking, methanol conversion, and toluene alkylation. 

Aluminum phosphate based molecular sieves, role in environmentally benign synthesis of chemicals, 128 Amines, organic isocyanate generation, 49-57... 

Zeolites, which are aluminosilicates that can be regarded as being derived from AI2O3 and SiC>2, function as acidic catalysts in much the same way (Section 7.3). In addition, they catalyze isomerization, cracking, alkylation, and other organic reactions. A structurally related class of micro-porous materials based on aluminum phosphate (AIPO4) has also been developed (Section 7.7) like zeolites, they have cavities and channels at the molecular level and can function as shape-selective catalysts. 

Potassium fluoride on alumina is a solid base.69 (It forms potassium hydroxide by exchange of fluoride for hydroxyl groups on the surface of the alumina.) An example of its use is given by Reaction 6.21.70 It has also been used without solvent in the Tishchenko reaction of benzaldehyde to give benzyl benzoate if 94% yield.71 Potassium fluoride on an aluminum phosphate molecular sieve was a weaker base in the isomerization of 1 -butene.72... 

Many of the techniques used to enrich PTMs at the protein level are applicable at the peptide level. A popular method for enrichment of phosphopeptides is to use an immobilized metal affinity column. The molecular basis for the enrichment is the phosphate affinity to transition metal ions, such as copper, nickel, cobalt, iron, aluminum, gallium, and zinc (142). A comprehensive source for phosphopeptide enrichment strategies can be found in a recent review (143). Lectin-based chromatography is used to enrich for glycopep-tides (144). Lectins are proteins that have an affinity for carbohydrates. With multiple available enrichment options, choosing the right one for the experiment is important. For determining which proteins have a certain PTM, protein-level enrichment can be performed. However, if a type of PTM is of... 

Melting point, 73 Relative density (water -1) 1.6 Solubility in water, g/100 ml at 20 C 121 Relative molecular mass 380.2 Qrossformula Na304P.12H20 COLORLESS CRYSTALS In aqueous solution is a medium strong base which reacts violently with acids and corrodes aluminum, zinc etc. Reacts with air to form disodium phosphate and sodium carbonafe. ... 

In particular, Alberti et al. (1991) proposed zeolite-based sensors for detection of hydrocarbons such as butane and Balkus et al. (1997) used thin film aluminophosphate (AlPO)-5 molecular sieve as the dielectric phase in a capacitance-type chemical sensor for CO and CO. AlPO-n is a family of phosphorus molecular sieves which, similar to zeolites, have ordered molecular-sized pores. The AlPO-5 structure used for the dielectric layer consists of four- and six-membered rings of alternating phosphate and aluminum ions bridged by oxygen. These rings are arranged to produce one-dimensional channels 0.73 nm in diameter. The properties of AlPO-n are reviewed in detail by Ishihara and Takita (1996), and one of the attractive properties of these materials is their heat stability. The properties of zeolites as they relate to zeolite-based gas sensors are discussed in a special section in Vol. 2. 

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