Tetrapropylammonium

A, A, A, A -tetramethylethylenediamine trimethyl orthoformate tetrapropylammonium perruthenate tetraphenylporphyrin sulfonated triphenylphosphine triisopropylbenzensulfonyl chloride triphenylcarbenium tetrafluoroborate tetrabutylammonium triphenylmethanethiolate toluenesulfonyl... 

Thus in the synthesis of BEA and MFI, tetraethyl- and tetrapropylammonium ions respectively, are most frequently applied as the templates. 

In the as-synthesized MFI-crystals the tetrapropylammonium (TPA) ions are occupying the intersections between the straight (parallel) and the sinusoidal channels of the zeolite, thus providing an efficient pore filling. The detailed structure of as-synthesized MFI-TPA has been elucidated by X-ray single crystal analysis (ref. 3). Also the combination tetrabutyl-Ztetraethylammonium can be applied as template in MFI-synthesis. A 1 1 build-in is found then (Fig. 1). When only tetrabutylammonium is available as template, the MEL (ZSM-11) lattice is formed with another distance between the channel intersections. 

Quaternary ammonium salt catalysts based on diff mt alkyl cations such as tetrapropylammonium (TPA, tetrabutylammonium (TBA, tetrahex5dammonium (THA ), tetraoctylammonium (TOA, tetradodecylammonium (TDodA, and those with different anions such as Q, Bf, and f were used. 

FIG. 8 Potential oscillation at interface o/wl with SDS as surfactant with (A) no electrolyte, (B) with lOOmM NaCl, (C) lOOmM KCl, (D) lOOmM CsCl, (E) lOOmM MgClz, (F) lOOmM CaClj, (G) lOOmM BaClj, (H) lOOmM FeClj, (I) lOOmM NaF, (I) lOOmM NaBr, (K) lOOmM Nal, (L) lOOmM sodium acetate, (M) 100 mM sodium propionate, (N) 100 mM sodium -butyrate, (O) lOOmM sodium w-valerate, ( ) lOOmM tetramethylammonium chloride, (Q) 20mM tetra-ethylammonium chloride, (R) 20 mM tetrapropylammonium chloride, and (S) 20 mM tetrabutyl-ammonium chloride in phase wl. Phase w2 contains 8mM SDS and 5M ethanol and phase o contains 5mM tetrbutylammonium chloride. (Ref. 27.)... 

FIG. 9 Upper potential values, a.sds lower potential values, b.sds of the first oscillation at the interface between phases o and wl of the octanol membrane (A), interfacial potential of a two-phase octanol-water system in the absence of SDS, c.sds (B) and those in the presence of 10 mM SDS (in the case of inorganic electrolyte, 1 mM), d.sds (C)- TMACI tetramethylammonium chloride TEACI tetraethylammonium chloride TPACI tetrapropylammonium chloride TBACI tetra-butylammonium chloride AcNa sodium acetate PrNa sodium propionate, BuNa sodium n-butyrate VaNa sodium w-valerate. (Ref 27.)... 

Silicalite-1 was synthesised according to published recipe [5], Fumed silica was added to an aqueous solution of tetrapropylammonium bromide and ammonium fluoride, and... 

In order to optimize oxidation conditions of diethyl(2-methylpyrrolidine-2-yl) phosphonate into the corresponding nitrone, a comparative analysis of the action of various oxidants such as H2O2, m-CPBA, Oxone, 2-phenylsulfonyl-3-phenyl-oxaziridine (PSPO), DMD, and A-methylrnorpholine /V-oxide in the presence of a catalytic quantity of tetrapropylammonium perruthenate (NMO/TPAP) has been made (92). 

Taramasso et al. (5) had originally reported two methods for the hydrothermal synthesis of TS-1. The first method (mixed alkoxide method) involves the preparation of a solution of mixed alkoxides of titanium and silica (preferably ethoxides) followed by hydrolysis with alkali-free solution of tetrapropylammonium hydroxide (TPAOH), distillation of the alcohol and crystallization of the resulting gel at 448 K. In the second method (dissolved or hydrolyzed titanium method) a soluble tetrapropylammonium peroxo-titanate species was prepared initially and then colloidal SiC>2 (Ludox AS-40) was added. This entire operation had to be carried out at 278 K. The TS-1 samples obtained by these two synthesis routes differed, particularly because of the presence of impurities such as Al3+ usually present in colloidal silica (33). 

In an attempt to produce TS-1 at low cost, alternative, cheaper sources of Ti and Si and other bases such as binary mixtures of (tetrabutylammonium and tetraethylammonium hydroxides), (tetrabutylphosphonium and tetraethylpho-sphonium hydroxides), (tetrapropylammonium bromide and ammonia, water, hexanediamine, n-butylamine, diethylamine, ethylenediamine, or triethanolamine) in place of TPAOH have been used (284—294). TS-1 was synthesized in the presence of fluoride ions but the material thus formed contained extraframework Ti species (295-297). 

Dissolved titanium method. Hydrothermal synthesis using tetrapropylammonium peroxytitanate (prepared from TEOT, distilled water, 30% aqueous H2O2, and 25% aqueous TPAOH) as the source of Ti and colloidal silica (Ludox AS-40) as the source of Si and TPAOH as template. All additions done at 278 K Preparation using TiCl2, 14% aqueous TPAOH, 30% colloidal silica, and demineralized water Preparation at low pH using fluoride ions as mineralizing agent... 

In ZSM-5 zeolite, almost every channel intersection is occupied by a tetrapropylammonium ion. Oppositely, tetrabutylammonium ions occupy preferentially the large cavities in ZSM-11 zeolite, the small cavities being only partially occupied. Their alkyl chains extend in the channel system in order to fill completely the available channel length (11). 

Howden, M. G.,"The role of tetrapropylammonium template in the synthesis of ZSM-5", CSIR Report CENG 413, Pretoria, 1982. 

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