Inorganic materials orthophosphate

Earlier, Mikhailenko et al. have introduced boron orthophosphate (BPO4) as an inorganic material (Mikhailenko et al. 1998). The composite SPEEK/BPO4 was able to increase the proton conductivity as the water uptake was also increased. There were no reported data on methanol permeability, but it was mentioned that the porosity of the membrane was increased. This chapter continues with more details on the SPEEK modification by using various types of inorganics such as Cloisite 15A, boron orthophosphate, and tungstosilicic acid supported on silica-aluminum oxide. 

Synthetic organic chelates and natural organic complexes are sometimes more effective agronomically per unit of micronuttient than inorganic forms, but the organic materials are more expensive. The chelates can be used with both orthophosphate and polyphosphate Hquids and suspensions. 

In the presynthetic surfactant era, soap was built (and still is) with alkaline salts such as soda ash, silicates, orthophosphates, and borates. These materials buffer the wash solution to a high pH and prevent soap protonation thus, the soap remains effective. Another type of builder is the neutral inorganic salt such as sodium chloride and sodium sulfate. These materials may improve detergency by increasing the ionic strength and altering the CMC of anionic surfactants. 

The retention model developed by Eon and Guiochon [7,8] to describe the adsorption effects at both gas-liquid and liquid-solid interfaces, which was later modified by Mdckel et al. [6] to account for the retention at chemically bonded reversed-phase materials in HPLC, is not applicable to ion chromatography. But if the dependence of the capacity factors of various inorganic anions on the column temperature is studied, certain parallels with HPLC are observed. The linear dependences shown in Fig. 3-2 are obtained for the ions bromide and nitrate when the In k values are plotted versus the reciprocal temperature (van t Hoff plot). However, in the case of fluoride, chloride, nitrite, orthophosphate, and sulfate, the k values were found to be constant within experimental error limits in the temperature range investigated. Upon linear regression of the values in Table 3-1, the following relations are derived for bromide and nitrate ... 

The solid-phase inorganic phosphates constitute a vast family of materials of considerable technological importance. Orthophosphate salts of most elements of the periodic table are known and may include minerals, synthetic products, acid salts, hydrates, and polymorphic varieties (17). The continuing scientific interest in phosphate materials reflects their practical applications as fertilizers, catalysts, phosphors, ion conductors, piezoelectric materials, biotechnological materials, and sorbents (18). 

Although the percentage of phosphorus in plant material is relatively low, it is an essential component of plants. Phosphorus, like nitrogen, must be present in a simple inorganic form before it can be taken up by plants. In the case of phosphorus, the utilizable species is some form of orthophosphate ion. In the pH range that is present in most soils, H2PO4 and HP04 are the predominant orthophosphate species. 

---