Phosphorus total

The total content of the elemental phosphorus in soils can be extracted and determined by perchloric acid digestion followed by spectrophotometric determination. 

The phosphate ion concentration in soil solution is essentially controlled by the heterogeneous equilibria of the form  

Several chemical extractants has been developed over the years from the concept of simulating plant root activity and with the purpose to obtain an appropriate measure of the readily soluble inorganic forms to represent the plant available soil P. Out of the several extractants, depending upon soil pH, presence of iron and aluminum compoimds or calcium carbonate one particular method is selected for analysis. The most common methods along with extractant composition, soikextractant ratio and shaking time are furnished below  

Methods Extractant composition Soil extractant ratio Shaking time (min) 

Morgan s method 10 ml of glacial acetic acid in 1 litre of 0.5% NaOH adjusted to pH 8.4. 1 5 30 

The determination of all groups of phosphates and phosphorus compounds is useful for the nutrient balance of a water since not only orthophosphate (hydrogen phosphate) but also hydrolyzable phosphates and organic phosphorus compounds can be utilized by organisms. 

It is also appropriate to determine the total phosphorus content if 

If determination of hydrogen phosphate and of total phosphorus is conducted in parallel, the difference between the two results provides a measure of 

Spectrophotometric determination following decomposition by acid and total hydrolysis to hydrogen phosphate ions 

Organic phosphorus compounds are converted to hydrogen phosphate ions by wet-ashing with sulphuric acid and hydrogen peroxide. The hydrolyzable 

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Table 1 Total phosphorus (TP) losses from different types of eatehment ...

Under optimum conditions of anaerobic and aerobic treatment in activated sludge plants, up to 90% removal of phosphorus can be achieved. Biological removal can, at best, achieve efffnent concentrations of about 0.2 mg total phosphorus but more usually reduces phosphorus to about ImgUh... 

The outlined scheme can also be used to calculate the amount of phosphoric acid triesters. In that case the difference must be formed of the total phosphorus content minus that of free phosphoric acid, phosphoric acid monoester, and phosphoric acid diester. The resulting value is then multiplied with the calculated molecular mass of the triester. 

Eberlein and Kattner [194] described an automated method for the determination of orthophosphate and total dissolved phosphorus in the marine environment. Separate aliquots of filtered seawater samples were used for the determination orthophosphate and total dissolved phosphorus in the concentration range 0.01-5 xg/l phosphorus. The digestion mixture for total dissolved phosphorus consisted of sodium hydroxide (1.5 g), potassium peroxidisulfate (5 g) and boric acid (3 g) dissolved in doubly distilled water (100 ml). Seawater samples (50 ml) were mixed with the digestion reagent, heated under pressure at 115-120 °C for 2 h, cooled, and stored before determination in the autoanalyser system. For total phosphorus, extra ascorbic acid was added to the aerosol water of the autoanalyser manifold before the reagents used for the molybdenum blue reaction were added. For measurement of orthophosphate, a phosphate working reagent composed of sulfuric acid, ammonium molyb-... 

Cambella and Antia [385] determined phosphonates in seawater by fractionation of the total phosphorus. The seawater sample was divided into two aliquots. The first was analysed for total phosphorus by the nitrate oxidation method capable of breaking down phosphonates, phosphate esters, nucleotides, and polyphosphates. The second aliquot was added to a suspension of bacterial (Escherichia coli) alkaline phosphatase enzyme, incubated for 2h at 37 °C and subjected to hot acid hydrolysis for 1 h. The resultant hot acid-enzyme sample was assayed for molybdate reactive phosphate which was estimated as the sum of enzyme hydrolysable phosphate and acid hydrolysable... 

Photo-oxidation was seen as a possible route to a total phosphorus method. Again, early work on the method was done by Armstrong et al. [15] and Armstrong and Tibbitts [36]. Grasshoff [37] adapted the method to continuous automatic analysis a variation on this method is considered the standard method for automatic analysis today [18]. Bikbulatov [38], on the other hand, feels that such important phosphorus compounds as ATP and DI are not completely decomposed by ultraviolet irradiation and that persulfate oxidation gives better results. 

Cembella et al. [40] have described a method for the determination of total phosphorus in seawater. The procedure used magnesium nitrate to oxidise organic compounds before standard molybdate colorimetric determination of ortho-phosphate. The method was applied to several pure organic phosphorus compounds and gave 93-100% recovery of phosphorus. 

Fig. 4 Redundance analysis (RDA) on phytoplankton communities collected during the surveys of 2005-2006 and their relationship with the environmental variables, such as the Total Phosphorus (PTOT), Water Flow (WATFL), Total Suspended Solids (TSS), ammonia concentration (NH4), nitrate concentration (N03), and conductivity (COND). Acronyms were also used for phytoplankton taxa representation...

With the use of the rapid fire detection and water deluge, there was no mass fire and the mix was ckrped into water for continued fire suppression. Any fire with RP results in the formation of white phosphorus (WP). WP must be covered with water since it ignites spontaneously when exposed to air. Processing studies were conducted to determine the best methods for pollution abatement since UP/water mixtures are toxic at 29 pob for blue gill bream and since high levels of phosphorus [reported as total phosphorus may not be durped into the environment. 

Total phosphorus content of phosphate rocks is relatively unimportant, since what really matters is its reactivity in the soil, which in turn depends on the soil itself, the rock mineralogy and the level of rock grinding. 

On-line phosphate measurement is more often limited to orthophosphates, the total phosphorus measurement needing a mineralization step that is difficult to carry out on site. However, some recent works have been published [27, 28] based on the use of a biosensor or of UV spectrophotometry (after reagent addition). The limit of detection is rather high for this analyte (0.5 mg L 1 or higher). 

Total oxidation reactions, in the presence of water, 19 87 Total oxygen demand (TOD) in wastewater treatment, 25 885 Total phosphorus content, determining,... 

Overall, the large number of significant differences among the fractions of all three bean types, reveals that the various minerals studied were not equally distributed among the fractions, except for sodium, but rather that partitioning occurred. Consistent with the ash values obtained, the protein flour fractions of the three bean types contained larger amounts of Fe, Mg, P, Z, and K whereas the starch II fractions contained smaller amounts of these minerals and Ca and Cu than the other flour fractions. Phytic acid content ranged from 8.7-30.2 mg/g for navy flours, from 4.3-23.7 mg/g for pinto flours. Total phosphorus content correlated well with both phytic acid content and protein content. Phytic acid content was... 

Suppliers of visible spectrophotometers are reviewed in Table 1.1. Spectroscopic methods are applicable to the determination of phenols, chlorophenols, amines, mixtures of organics, boron, halogens, total nitrogen and total phosphorus in soils, cationic surfactants, carbohydrates, total nitrogen, phosphorus and sulphur in non-saline sediments, boron, total organic carbon, total sulphur and arsenic in saline sediments, cationic surfactants, adenosine triphosphate and total organic carbon in sludges. 

This technique has found very limited applications in soil and sediment analysis and is particularly useful when routine automated analyses at the mg L 1 level of large numbers of samples is required. The technique has been applied to the determination of total phosphorus, total organic carbon and total nitrogen in soils, total organic carbon in non-saline sediments and total sulphur in saline sediments. 

This technique has been applied to the determination of boron, total phosphorus and arsenic in soil, antimony and organosilicon compounds in non-saline sediments, arsenic in saline sediments and silicon and arsenic in sludges. 

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