Organophosphorus separation

Marutoiu C, Sarbu C, Vlassa M, et al. 1986. A new separation and identification method of some organophosphorus pesticide by means of temperature programming gradient thin-layer chromatography. Analysis 14 95-98. 

Marutoiu C, Vlassa M, Sarbu C, et al. 1987. Separation and identification of organophosphorus pesticides in water by HPTE. J High Resolution Chromatog Chromatog Comm 19 465-466. 

The use of t.l.c. for separating organophosphorus compounds has been reviewed. In a study of phosphoryl compounds it was shown that / m values i.e. log [(1 - Rv)lRy on silica gel using hexane-acetone as eluant, depend upon the polarity of the P=0 group.The migration order found was... 

Absorbance detectors are also commonly used in combination with postcolumn reactors. Here, most issues of detector linearity and detection limit have to do with optimization of the performance of the reactor. In a typical application, organophosphorus compounds with weak optical absorbances have been separated, photolyzed to orthophosphate, and reacted with molybdic acid, with measurement being performed by optical absorbance.58... 

In spite of their toxicity, alkyl phosphites have been used extensively as lubricant additives, corrosion inhibitors, and antioxidants. In addition to their use as intermediates in synthesis, organophosphorus compounds are useful for separating heavy metals by solvent extraction. Several insecticides that were formerly in widespread use are derivatives of organic phosphates. Two such compounds are malathion and parathion. 

Whereas ligand selection for the biphasic water-organic and the induced phase separation system are somewhat limited, there is very wide array of organophosphorus... 

Selective Condensation of Vaporized Organophosphorus Ligand. Certain phosphorus ligands have sufficient volatility that portions may be volatilized when aldehyde and higher boiling aldehyde condensation byproducts are separated from the catalyst solution in, for example, a liquid recycle vaporizer. The phosphorus ligand may be condensed, recovered and returned to the catalyst solution [35] according to the procedure disclosed in US 5,110,990. 

The plutonium concentration in marine samples is principally due to environmental pollution caused by fallout from nuclear explosions and is generally at very low levels [75]. Environmental samples also contain microtraces of natural a emitters (uranium, thorium, and their decay products) which complicate the plutonium determinations [76]. Methods for the determination of plutonium in marine samples must therefore be very sensitive and selective. The methods reported for the chemical separation of plutonium are based on ion exchange resins [76-80] or liquid-liquid extraction with tertiary amines [81], organophosphorus compounds [82,83], and ketones [84,85]. 

Chlorodialkylphosphines are important synthetic intermediates in organophosphorus chemistry. In the chemical literature there is a widespread view that the simple one-step Grignard method is not suitable for the preparation of these compounds because of dominant trisubstitution and the formation of difficultly separable mixtures.12 Although this is true for the w-alkyl compounds, the present preparation demonstrates that in the case of branched primary alkyl compounds and secondary and tertiary alkyl compounds the method can be very convenient and can give pure products. The submitters have prepared 13 chloro-diisobutylphosphine (45-50%), chlorodi-sec-butylphosphine (75-80%), chlorodi-f-butylphosphine (65-70%), and chlorodicyclo-hexylphosphine (60-65%) in analogous manner. 

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. 

The stationary phases coated on the inert supports are similar in the two classes of columns. Liquids of different polarities are chosen for the separation of non-polar or polar compounds a relatively small number of solvents, chemically inert and heat resistant, are sufficient for most residue analyses. The most commonly used for organophosphorus compounds vary from low-polarity hydrocarbons, methylsilicones, phenylsilicones, phenylmethylsilicones or carboranesiloxanes 165 168 175 178 180 182 184 192,195,197,198,... 

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