Chemistry of phosphomolybdate adsorption on alumina surfaces. 2. The molybdate/phosphated alumina and phosphomolybdate/alumina systems

Journal Article · Thu Jun 28 04:00:00 EDT 1990 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100376a022· OSTI ID:6379175

van Veen, J A.R.; Hendriks, P A.J.M.; Andrea, R R; Romers, E J.G.M.; Wilson, A E ^[1]

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1. Shell Research B.V., Amsterdam (Netherlands)

The adsorption of ammonium heptamolybdate (AHM) on phosphated alumina and of P{sub 2}Mo{sub 5}O{sub 23}{sup 6{minus}} and PMo{sub 12}O{sub 40}{sup 3{minus}} on {gamma}-Al{sub 2}O{sub 3} has been studied by using FTIR, Raman, and {sup 31}P solid-state NMR spectroscopies, and TPR. Adsorption of phosphate prior to contacting of {gamma}-Al{sub 2}O{sub 3} with AHM leads to a deactivation of the alumina surface still remaining. Phosphate reacts with {gamma}-Al{sub 2}O{sub 3} to form an AlPO{sub 4}-type surface phase, which itself is capable of adsorbing molybdate, with the formation of an irreducible surface molybdophosphate, its adsorption capacity being lower, however, than that of the original alumina. The primary phosphomolybdate adsorption reaction on alumina is shown to be the same as that observed in the case of AHM, viz., a reaction with the basic surface OH groups, leading to the decomposition of the adsorbing species.

• OSTI ID: 6379175
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 94:13; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ADSORPTION
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CATALYSTS
CHALCOGENIDES
DATA
DATA ANALYSIS
EXPERIMENTAL DATA
INFORMATION
MEASURING INSTRUMENTS
MEASURING METHODS
MOLYBDATES
MOLYBDENUM COMPOUNDS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PHOSPHATES
PHOSPHORUS COMPOUNDS
REFRACTORY METAL COMPOUNDS
SORPTION
SURFACE PROPERTIES
TRANSITION ELEMENT COMPOUNDS