Bismuth ammonium molybdate

Bl-MoOg was prepared by the method of Vedrlne et al O). Bl CMoO ) and Bl-FeMo 0.- were prepared by copreclpltatlon of bismuth nitrate, ferrlc nltrate and ammonium molybdate. After drying, the catalysts... 

Bismuth cerium molybdates were prepared by coprecipitation using aqueous solutions of (NH ) Mo 02, (NH,)2Ce(N0 ), and Bi(NO ) 5H2O. The catalysts were supported on oiO (20% by weight) using an ammonium stabilized silica sol. Samples for diffraction analysis were unsupported. Samples were calcined in air at 290 and 425°C for three hours each followed by 16 hours at 500, 550, or 600 C. X-ray powder patterns were obtained using a Rlgaku D/Max-IIA X-ray diffractometer using Cu K radiation. 

A more complex but sensitive IC method was developed by Antony et al. based upon separation using a Dionex AS4A-SC column and postcolumn derivitization of phosphate using a solution containing 0.5% w/v ammonium molybdate and 0.5% w/v bismuth nitrate, in 1.75 M H2SO4 and 0.75% ascorbic acid. The resultant reduced ion association complex absorbed strongly at 700 nm and a detection limit for phosphate (P) of an impressive 0.8 /rg/1. The above chemistry has also been exploited in a recent publication by Haberer and Brandes " who carried out precolumn derivitization of phosphate within freshwater and saltwater samples and then solvent extracted the resultant molybdenum blue complex prior to separation and detection (at 700 nm) using reversed-phase HPLC. 

Acacia Acetylated lard glyceride Acrylic acid/acrylamide copolymer Adipic acid Allyltrimethoxysilane Allyltrimethyl silane Aluminum orthophosphate N-(2-Aminoethyl)-3-aminopropyl methyidimethoxy silane 3-Aminopropylmethyldiethoxysilane Aminopropyltrimethoxysilane Ammonium hydroxide Ammonium molybdate (VI) Ammonium ricinoleate Amyltrichlorosilane Arachidyl alcohol Barium petroleum sulfonate Bis (dimethylamino) dimethylsilane 3-[Bis (2-hydroxyethyl) amino] propyltriethoxysilane Bis-(N-methylbenzamide) ethoxymethyl silane Bismuth... 

Molybdate-Based Catalysts. The first catalyst commercialized by SOHIO for the propylene ammoxidation process was bismuth phosphomolybdate, Bi9PMoi2052, supported on silica (9). The catalytically active and selective component of the catalyst is bismuth molybdate. In commercial fluid-bed operation, the bismuth molybdate catalyst is supported on silica to provide hardness and attrition resistance in the fluidizing environment. Bismuth molybdate catalysts can be prepared by a coprecipitation procedure using aqueous solutions of bismuth nitrate and ammonium molybdate (10). The catal3ret is produced by drying the precipitate and heat treating the dried particles to crystallize the bismuth molybdate phase. Heat treatment temperature for bismuth molybdate catalysts is generally arovmd 500°C. 

Aldoses and ketoses, similar to aldehydes, reduce heated Tollens reagent (see p. 210), Nessler s reagent (p. 211), Fehling s reagent [p. 210 see also (55)], and also Nylander s reagent (an alkaline solution of a bismuth salt) and a solution of ammonium molybdate. The reaction with nitro compounds should also be mentioned here. 

It was once widely used to make acrylonitrile by reaction with acetylene in presence of an aqueous cuprous chloride-ammonium chloride catalyst, but this process is obsolescent and is being displaced by ammoxidation of propene with bismuth molybdate catalysts ... 

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