The apparent effectiveness of the precipitated phosphates relative to that of MCP was, expressed as a percentage by E = x 100 where M is the rate of P applied as MCP. corresponding to the same total P offtake given by the precipitated phosphate. 15 The recovered calcium phosphate gave the lowest recorded total P offtake of the precipitated phosphates and a value of 69% for E. The iron phosphate gave somewhat larger DM yields but slightly smaller P offtakes to those given by MCP at 0.087 g P per pot with a value of 85% for E. It has generally been considered that iron phosphates are insoluble and that the P they contain is unavailable to plants.

The process of preparing substantially pure Ortho-phosphoric acid, which comprises Subject ing tri-calcium phosphate-containing material to the action of sulphuric acid in Such amount 60 and of such strength as to convert the tri-calcium phosphate substantially completely to mono-cal cium phosphate but insufficient to convert more than a minor portion thereof to free phosphoric acid, adding sufficient neutralizing agent to re 65 duce the acidity of the mixture to at least a pH value of 4.4, separating the mono-calcium phos phate in the form of a dilute aqueous solution 55 phosphoric acid. The process of preparing substantially pure obtained with lime, Separating the precipitated di calcium phosphate from the Water and the impuri ties dissolved or Suspended therein, washing said precipitate, treating said precipitate with 66 Bé. or stronger sulphuric acid to convert the phos phate to Ortho-phosphoric acid, Separating the 60 precipitated gypsum from the solution of phos phoric acid, decolorizing said Solution by treat ment with a suitable oxidizing agent, Subjecting said Solution to the action of hydrogen Sulphide for the removal of arsenic, and finally concentrat ing the resulting Solution of pure Ortho-phosphoric acid to the desired strength.

Flame Retardants for Polymeric Materi... Flame-retardant epoxy resins: An approach from organic-inorganic hybri... Flame-retardant epoxy resins from novel phosphorus-containing novolac Polymer Combustion Processes. Polymerisation of 1-oxo-2,6,7-trioxa-1-phosph... Degradation of phosphorus-containing polyurethanes Thermo-oxidative degradation of phosphorus-containing polyurethane Thermochemical and chemical kinetic data for fluorinated hydrocarbons Phosphorus-bromine flame retardant synergy in engineering thermoplasti... Synthesis and characterization of phosphorus-containing polyurethanes A Phosphorus-Bromine Flame Retardant for Engineering Thermoplastics-A ....

The feasibility of recycling phosphates in the white phosphorus production process is explored, with a focus on various materials that may be recycled. For effective recycling, the materials must be dry, low in iron, copper, and zinc. Manure ash and sewage sludge ash can be used for recycling provided they meet the iron requirement. However, copper and zinc levels in the ash may pose a problem for recycling. The side stream P recovery method may be promising, but it requires further more in-depth research. Overall, the recycling of phosphates from industrial sources is possible, but the effectiveness depends on the source materials. Therefore, additional research and development need to be conducted to explore a wider range of options for efficient recycling of phosphates.

Such un group consisting of chlorine and bromine, Ra is a mem substituted hydrocarbon groups are represented by and ber of the group consisting of hydrogen and alkyl radi include the alkyl groups, such as methyl, ethyl, propyl, cals, and R4 is a member of the group consisting of such as phenyl, tolyl, naphthyi, and the like, aliphatically hydrogen, chlorine, bromine, and the alkyl radicals. 70 novel reaction can be described as leading to displace The hydrocarbon group or groups which may be sub ment of one alcohol residue from the ester of the acid stituted on the alpha and/or beta carbon atoms of the of trivalent phosphorus by the residue of the beta-halogen residue of the beta-halogen-susbtituted alpha,beta-olefini Substituted alpha,beta-olefinically unsaturated alcohol cally unsaturated alcohol include unsubstituted hydrocar which corresponds to the enolic form of the halogen-sub bon groups and hydrocarbon groups which include one or 75 Stituted carbonyl compound having one less alpha halogen 5 2,956,08 than the halogen-substituted carbonyl compound actually employed and to conversion of the phosphorus atom.

The study investigated biological phosphorus removal under anoxic and aerobic conditions to establish whether phosphorus accumulating bacteria can uptake phosphate under anoxic conditions, using nitrate as an oxidant. Batch experiments were conducted in 21 reactors using activated sludge from two pilot plants incorporating phosphorus removal. The results indicated that the phosphorus accumulating bacteria in the samples could be divided into two groups based on process, one group able to use oxygen and nitrate as oxidants, while the other could only use oxygen. Phosphorus uptake was faster under aerobic conditions, as all the phosphorus accumulating bacteria took up phosphate, whereas only part of the bacteria did so under anoxic conditions. The study also showed a linear relationship between the amount of acetate taken up during the anaerobic phase, denitrification rate, and phosphorus uptake rate. It concluded that organic matter taken up by phosphorus accumulating bacteria during the anaerobic phase affects the total denitrification rate and the rate at which the bacteria take up phosphate under anoxic conditions.