On-line analysis of organic phosphorus compounds with P-O-C and P-C bonds have been developed based on HPLC and two-step postcolumn reactions. The calibration curve for the organic phosphorus compounds showed good linearity (correlation coefficient>0.9918). The standard deviations (n=9) of the method were smaller than 0.91%. The detection limits (S/N=2) of the organic phosphorus compounds were ca. 0.5 nmol as the injected amount. This method could be applied to the determination of the organic phosphorus compounds in the 5-100 μM range (injection volume, 100 μl).

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SrNiZn(PO₄)₂ is isostructural to SrNi₂(PO₄)₂ [P-1, Z=2, a=5.4560 (10), b=6.7110 (10), c=9.1820 (10), α=110.600 (10), β=101.100 (10), γ=98.080 (10), 1009 independent reflexions (I>2σ(I)), 119 parameters, R1=6.98, wR=7.03], with sheets made of edge-sharing [NiO₆] and [ZnO₅]. However in the new compound, Ni form dimers [Ni₂O₁₀] with short d_Ni-Ni of 3.006 Å.

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Ultraphosphate structures are polymeric and consist of the anion framework and the cations between. But, the anion framework strongly depends on the cations, their charge, size, and value. Some selection rules exist, which point out the number of possible structure bonds related to the number and charge of the cations. Concerning anion framework, there exist discrete cyclic units as well as ribbons and layer structures with different ring sizes, number of connecting {PO₄} tetrahedra and connection possibilities. The cations are isolated from the others within the frameworks because of their low content. But, when the cations were connected each other with thinkable bonds, we get a detailed insight into the structure interactions between anion configurations and the cations between. In all evaluated crystalline ultraphosphate structures, the cations have 6 cations “around” to form octahedra with different distances and symmetries from one cation to the next neighboured one. The so-called repeatable units seem to depend on the complexity of the anionic framework: the more complex the anionic structure, the less complicate the cationic relations, and reversed. This means, that ultraphosphate structures possess strong relations between the {_PO4} groups and the cations. The result are complex interconnecting structures.

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Processing of phosphogypsum on sulfoaluminate-silicate cement allows to receive decorative and usual rapid-setting cements of mark 400-600. In comparison with white Portland cement it allows to save a significant amount of technological fuel. Productivity of the furnace raises on 15-25% for the account of lower contents of limestone in a raw mix of sulfoaluminate-silicate cement in comparison with Portland cement a raw mixture. We have investigated the behaviour of phosphorus in this process.

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Titanium ethyl phosphates (TiEP) synthesized by the reaction of Ti(SO₄)₂ with a mixture of mono- C₂H₅OPO₃H₂ and diethyl phosphates (C₂H₅O)₂PO₂H (EP) in aqueous media were characterized by various means. XRD pattern of TiEP featured a strong diffraction peak at 2θ=6.8°. When TiEP was treated at 900°C in air, the material crystallized as TiP₂O₇, implying the molar ratio P/Ti of TiEP to be 2.0. This indicates that only monoethyl phosphate ions reacted with Ti⁴⁺ ions. The chemical formula of TiEP could be shown as (C₂HSOPO₃)₂Ti·1.7H₂O. These facts suggested that TiEP is composed of a multilayer alternating bimolecular layer of ethyl phosphates and hydrated titanium phosphate phase. Ethyl groups and H₂O molecules in the layers were removed by outgassing at 200°C to give the materials having mesopores with a diameter of ca. 2.6nm

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Adsorption of polyethyleneglycol mono-p-isooctylphenylether (TX-100) on hydroxyapatite (HAP) was accelerated in the presence of sodium dodecylsulfate (SDS). This is because TX-100 was captured into hemimicelle/ admicelle of SDS formed on the surface of HAP. The adsorption amount on and affinity to HAP of TX-100 increased with the adsorption amount of SDS, forming the mixed micelle on the surface. Sodium dodecylbenzenesulfonate (SDBS) was also adsorbed on HAP in the same manner as that of SDS. However, polyoxyethylene (23) laurylether (C12n23) was little adsorbed by itself and scarcely accelerated the adsorption of SDBS. Anionic surfactants such as SDS and SDBS were adsorbed directly on the surface, while nonionic surfactants such as TX-100 and C12n23 required hydrophobic area to be adsorbed on the surface. The hydrophobic patch on the surface should be formed after the adsorption of the anionic surfactant on HAP. The roles of hydrophobic interaction and cooperative adsorption in the adsorption of nonionic surfactants were discussed.

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Hydroxyapatites (HAPs) containing carbonate were sintered between 400 and 1200°C, and the sintered HAPs were analyzed by FT-Raman spectroscopy to give the spectra indicating typical four phosphate bands ν₁(PO₄)-ν₄(PO₄), OH translation ν₅, notable bands ν₆-ν₈ in lattice modes, and several combination bands. The band intensities of ν₂(PO₄)+ν₅ and ν₁(PO₄), and these intensity ratio R_cp values were changed according to the carbonated types in the HAPs. From these results, we conclude that the changes in Raman intensities possibly reflect the particle growth and volume shrinkage in the HAPs. The present Raman study may be applied to structural elucidation study of other substituted apatites such as fluorinated and magnesium apatites as well as forensic study.

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The influence of temperature (20°-1000°C) on substrates Zn₃(PO₄)₂ 2H₂O (1), MgHPO₄·3H₂O (11) and their binary mixtures in percentage ratio from 10%-90% (2-10) was investigated. The researches were done in mean of differential thermal analysis (TG, DTG, DTA), IR-spectroscopy, electron microscopy, and WARS-Ray. On the grounds of mentioned above analytical methods, there was stated that Zn₃(PO₄)₂·2H₂O-Hopeite and MgHPO₄·3H₂O-Newberyite both occur in crystalline form. Heating these substrates to 500°C cause transformation to Zn₃(PO₄)₂ and Mg₂P₂O₇. On the thermal curves (DTA) this transformation is pointed until at 670°C. This is caused by the transformation this substrate to amorphous forms. Further heating of substances even to 1000°C don't cause other transformation. Additionally, Zn₂Mg(PO₄)₂ was made from binary mixtures, during heating in oven at 1000°C in any percentage ratio. This was brought about the phenomenon of fluidisation of Mg₂P₂O₇.

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Three powder samples of lanthanum phosphate were prepared via the precipitation method. La₂O₃, LaCL₃, (NH₄)₃PO₄ and H₃PO₄ were used as precursor materials. Chemical and thermal analyses, infrared spectra, X-ray diffraction and particle size techniques were used for characterization. The results of chemical analysis indicated that the three samples are in non-stoichiometric state which attributed to the solubility of the products in the aqueous medium and/or to the partial precipitate of HPO₄^2- and H₂PO₄^- species. The results of infrared spectra exhibited the specific bands of phosphate salts such OH, O=P-O, P-O and O-P-O. A band at 1380 cm^-1 corresponding to PO₂^2- is observed in sample I and II which may due to make complexation species between the phosphates and the metal ions.
The X-ray diffraction indicated the formation of lanthanum phosphates of hexagonal structure of rhabdophane LaPO₄.0.5H₂O. DTA/TGA curves show that the prepared samples remain thermally stable at high temperatures.

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Substituted AlPO₄ and FePO₄ with Na⁺ and Cd⁺² were synthesized by sol-gel method from H₃PO₄ and the chloride salts using ethylene oxide as a gelating agent. Chemical analysis, Infra red spectra and x-ray diffraction were measured for characterizing the products. Electrical conductivity of the samples, dried and sintered at 550°C, was performed.
The results of characterization indicate that the substitution process depends on the mole%of the substituant cations where they improved the crystallinity of the formed phases. The electrical conductivity measurements indicated that the prepared phosphates behave as semiconductor materials and its value depends on the nature of cations, and the thermal treatment.

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Thermal changes in synthetic apatites (Aps) at calcination up to 1000°C were studied by TG/DTA, FTIR and XRD. The Aps containing CO₃ ^2-, SO₄ ^2-, F^-, and Na⁺ substitutions were precipitated from aqueous solutions. Reorganization of CO₃ ^2- and SO₄ ^2-substituted Ap structure takes place in a temperature range of 600-930°C and the substitutes are displaced. The temperature of the changes decreases with an increase in F content in Ap. In F containing Ap SO₄ ^2- displaces in one-step and CaSO₄ is formed. From hydroxyapatite structure SO₄ ^2- disengages continuously up to 1000°C. CO₂ evolves in 1-3 steps. If C/P≈0.3, most of CO₂ (70%) evolves at 700-800°C and CaO [Ca(OH)₂] is formed. If C/P≈0.1, most of CO₂ evolves at 830°C.

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Thermal reactions of SO₂ with natural and synthetic apatites (Aps) have been studied by thermogravimetric analysis. Experiments under dynamic and isothermal conditions were performed in the air-SO₂ flow with different SO₂ content (0.07%, 1%, 10%). The reactions proceeded at temperatures from 400°C to 800-850°C according to two- or three-dimensional diffusion models, the reaction rate depending on temperature, SO₂ concentration and substitutions in the Aps structure (PO4↔CO₃). Thermal interaction of Aps with SO₂ led to decomposition of apatite. At heating during one hour at 800°C in an air-SO₂ (10%) flow, 40% of fluorine from fluorapatite (FAp) and 72% from carbonateapatite (FCO ₃Ap) was removed.

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Zinc oxide-ammonium dihydrogenphosphate-urea mixtures were heated in a stream of nitrogen gas to obtain a large amount of cyclo-tetraphosphate. A trace of cyclo-tetraphosphate was formed only at 500°C and with the molar ratios of urea/ZnO/NH₄H₂PO₄ of 1/1/2 and 2/1/2. Instead of the cyclo-tetraphosphate, zinc polyphosphate (β-Zn(PO₃)₂) with long-chain anion was a main product above 400°C.

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Ammonium polyphosphate (APP) form II was prepared by heating a mixture of ammonium orthophosphate and urea at 280 to 300°C under wet ammonia which was made by passing air through 3 to 5% ammonia water. Simple dry process of the preparation of APP form V was studied and APP form V was prepared by heating a mixture of ammonium orthophosphate and urea at 330 to 340°C under wet ammonia which was made by passing air through 15 to 29% aqueous ammonia. These APPs showed an oxygen index higher than 26 when they were added to synthetic organic polymers.

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Oxidative coupling of methane to ethylene and ethane has been investigated on binary hydroxyapatite catalysts; calcium-lead hydroxyapatite (CaHAp-PbHAp) and barium-lead hydroxyapatite (BaHAp-PbHAp) at 973 K. Although BaHAp, CaHAp and PbHAp were inactive for the oxidative coupling of methane, those binary hydroxyapatites afforded C₂ compounds rather selectively. During the oxidation on CaHAp-PbHAp catalysts, those catalysts were mainly converted to Ca_5.5Pb_4.5(PO₄)₆(OH)₂ to afford great activities while an unfavorable conversion of CaHAp to Ca₃(PO₄)₂, which was inactive for the oxidation of alkanes, was rather suppressed. In contrast, BaHAp in the BaHAp-PbHAp catalysts was extensively converted to inactive Ba₃(PO₄)₂, resulted in the complete deactivation on BaHAp-PbHAp, particularly on PbHAp-rich catalysts.

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The lead removal ability of two kinds of board-shape hydroxyapatites with different Ca/P molar ratio were evaluated. The samples reacted with Pb(NO₃)₂ in an aqueous solution produced a mixture of hydroxyapatite and hydroxypyromorphite. The results showed that Board-shape Ca-deficient type HAP(HAP-400) has Pb²⁺ removal ability superior to Board-shape HAP with stoichiometric composition(HAP-300).

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The activity of AlPO₄ for C₂H_4-SCR-NO was examined and discussed on the basis of its reaction pathway. The conversion of NO to N₂ in C₂H₄-SCR-NO over AlPO₄ was very low, because of its low NO oxidation ability to form NO₂. Therefore, C₂H_4-SCR-NO over several metal-loaded AlPO₄(M/AlPO₄) was also investigated to achieve higher activity.

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The oligomerization of ethene was investigated over several catalysts involving Ni/SiO₂·Al₂O₃(Ni/SA) and BPO₄. The oligomerization of ethene activity of SA or BPO₄ was very low, while that of Ni/SA was very high. Butene was predominantly observed over Ni/SA, while no product was observed over BPO₄. Combined use of Ni/SA and BPO₄ was more effective for promoting the ethene oligomerization than Ni/SA, especially for increasing C₆ fraction. 1-Butene as C₄ products in the ethene oligomerization was mainly obtained in the presence of Ni/SA alone, while an equilibrium mixture of n-butene was formed using Ni/SA and BPO₄ together, suggesting that the isomerization of n-butene formed from ethene occurs over BPO₄.

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