Decomposition of organophosphorus compounds

Adsorption and Decomposition of Organophosphorus Compounds on Clay Minerals and Metal Oxides... 

Y.-X. Li et al., Adsorption and decomposition of organophosphorus compounds on nanoscale metal oxide particles. In situ GC-MS studies of pulsed microreactions over magnesium oxide. Chem. Mater. 4, 323-330 (1992)... 

APPLICATIONS OF TRANSITION METALS AND METAL OXIDES AS CATALYSTS FOR ADSORPTION AND DECOMPOSITION OF ORGANOPHOSPHORUS COMPOUNDS... 

A QUEST FOR EFFICIENT METHODS OF DISINTEGRATION OF ORGANOPHOSPHORUS COMPOUNDS MODELING ADSORPTION AND DECOMPOSITION PROCESSES... 

Most chemical methods for the analysis of organophosphorus compounds involve the initial decomposition and conversion of the P into orthophosphate which can then be analysed by the chemical methods outlined above. Preliminary procedures are, however, often essential and are frequently highly specific to the particular analytical problem involved. These procedures can involve extraction, cleanup, separation and identification, which frequently incorporate the use of physical methods. 

In more complex flow-injection systems the organophosphorus samples are injected without previous mineralization, and all decomposition reactions are carried out in the instrument itself oxidation of organic compounds by digestion with, for instance, per-oxodisulphate in a heated capillary tube18,19 or hydrolysis of di- and tri-phosphates with... 

Organophosphorus substances are often found in mixtures containing several compounds and their decomposition products. The analysis of such a multi-component sample requires the separation of the individual derivatives before identification and determination are possible. A number of techniques of general applicability are available to this end, mostly based on chromatography and mass spectrometry. In addition, methods have been developed for the analysis of individual compounds requiring no previous separation. 

Ultrasonic extraction, also known as sonication, uses ultrasonic vibration to ensure intimate contact between the sample and the solvent. Sonication is relatively fast, but the extraction efficiency is not as high as some of the other techniques. Also, it has been reported that ultrasonic irradiation may lead to the decomposition of some organophosphorus compounds [12]. 

This review summarizes experimental and theoretical studies which are used to develop theoretical models that explain and predict how clay minerals and metal oxides can affect the adsorption and decomposition of selected organophosphorus compounds. The results can contribute to a better knowledge of the impact of such processes on existing remedial technologies and in the development of new removal and decomposition techniques. 

For sometime, phosphinidines, monovalent organophosphorus species with the general formulation (R-P), have been postulated as reactive intermediates in the thermal and photochemical decomposition of several types of stable organophosphorus compounds. While not isolated as stable molecules, these monovalent species can be inferred on the basis of the isolation of products whose structures can be derived rationally from the postulation of such species, as well as on the mass spectra of the transient species themselves. We may view phosphinidines as the phosphorus analogues of nitrenes (R-N), highly reactive monovalent nitrogen species formed as transient intermediates in the thermal decomposition of azides and in the a-elimination reaction of A-tosylates. 

Canavan, A.E., and Eabom, C., Organosilicon compounds. Part 22. The thermal decomposition of some silicon-substituted organophosphorus compounds. J. Chem. Soc., 592, 1962. 

Fiszer, B., Organophosphorus compounds wilh an active methylene group. Part 5. Thermal decomposition of diethoxyphosphiny lace tic acid. Rocz. Chem., 37, 949, 1963. 

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