Nickel orthophosphate

Nickel Phosphate. Tri nickel orthophosphate [14396-43-17, Ni2(P0 2 7H20, exists as apple-green plates which decompose upon heating. It is prepared by the reaction of nickel carbonate and hot dilute phosphoric acid. Nickel phosphate is an additive to control the crystal size of ziac phosphate ia coaversioa coatiags which are appHed to steel prior to its being paiated (see Metal surface treatments). 

Nickel Orthophosphate, Ni3(P04)2.7H20, may be prepared by adding sodium orthophosphate to a solution of a soluble nickel salt.7 It is pale green in colour, turning to yellow when heated.8 A double... 

Electron microscopic examination of these catalysts showed that the powders that exhibited Type A behavior had many particles less than 10 nm in diameter, whereas the powders showing Type B characteristics had relatively few of these small particles. 2 similar size effect was reported for Ni(P) catalysts prepared by the reduction of nickel orthophosphate.93 When the catalyst was reduced at temperatures near 400°C, Type A behavior was observed, whereas Type B behavior occurred with catalysts prepared at higher reduction temperatures. Here, too, a particle size effect was proposed to explain these results. Lower temperature reduction gives fine clusters of Ni interspersed with the Ni(P), and it was considered that these small particles were more effective for... 

The metal ion specificity for the reaction with acetate was different from that in the reaction with phosphate in the former beryllium was most active, followed by nickel. The alkaline earths that were so effective with phosphate did not catalyze the reaction with acetate at all. The difference in metal specificity in the two reactions was explained by assuming that complexation with the orthophosphate and acetate constitutes an important function in the reaction. 

Nickel Thio-orthophosphate, Ni3(PS4)2, is obtained by heating the requisite quantities of anhydrous nickel chloride and phosphorus pentasulphide in a retort4 ... 

Over the past 30 years, metal orthophosphates have been used as catalysts for a variety of organic processes [1]. Most are active in the gas-phase dehydration of alcohols and some such as Caio(OH)2(P04)6 [2], Zn3(P04)2 [3] and calcium nickel phosphate [4] exhibit a dehydrogenating ability in the conversion of secondary alcohols into ketones. More recently, mixed orthophosphates including NaZnP04 [5] and NaMgP04 [6] have been used as catalysts for the dehydrogenation of alcohols. 

Many orthophosphate minerals contain more than one kind of metal atom. However, mixed-metal orthophosphates can be synthesised in great variety - with sodium and nickel, for example, there are at least six different compounds ... 

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