Hydrolysis of an organophosphate ester by manganese dioxide.
Amorphous manganese dioxide facilitates the hydrolysis of p-nitrophenyl phosphate to p-nitrophenol and orthophosphate despite insignificant adsorption of p-nitrophenyl phosphate or p-nitrophenol to the manganese dioxide. At pH 8, the orthophosphate product is released into solution; at pH 4 and pH 6, some remains adsorbed. The rate of hydrolysis is an order of magnitude more rapid than the same reaction facilitated by iron oxides. Because manganese dioxides are ubiquitous components of soils and sediments, this suggests the possibility of significant abiotic pathways for the formation of bioavailable orthophosphate from phosphate ester precursors.
Baldwin
D S
DS
Murray-Darling Freshwater Research Centre and the CRC for Freshwater Ecology, P.O. Box 291, Albury, New South Wales 2640, Australia.
Beattie
J K
JK
Coleman
L M
LM
Jones
D R
DR
D001682:Biological Availability; D002863:Chromogenic Compounds / Q000737:chemistry*; D006868:Hydrolysis; D017895:Manganese Compounds / Q000737:chemistry*; D009596:Nitrophenols / Q000737:chemistry*; D009943:Organophosphorus Compounds / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D012989:Soil Pollutants
D002863:Chromogenic Compounds; D017895:Manganese Compounds; D009596:Nitrophenols; D009943:Organophosphorus Compounds; D010087:Oxides; D012989:Soil Pollutants; C008644:nitrophenylphosphate; C016552:manganese dioxide