Chelating agents and

Ophthalmic ointments usually contain petrolatum as the base. The petrolatum is sterilized by dry heat and combined with the sterile dmg powder under aseptic conditions. Ophthalmic suspensions contain very fine (- 10 ji) particle sized soHds suspended in an aqueous vehicle. The vehicle is adjusted to isotonicity and viscosity-increasing excipients, chelating agents, and surfactants also may be needed. The aqueous vehicle in these cases is generally autoclaved and mixed with sterile dmg powder asceptically (30). 

Metal poHshes may contain emulsifiers and thickeners for controlling the consistency and stabilization of abrasive suspensions, and the product form can be soHd, paste, or Hquid. Liquid and paste products can be solvent or emulsion types the market for the latter is growing. Formulas for metal poHshes are Hsted ia Reference 12. A representative Hquid emulsion product may contain 8—25 wt % abrasive, 2—6 wt % surfactant, 0—5 wt % chelating agents, and 0—25 wt % solvent, with the remainder being water. The abrasive content ia an emulsion paste product is greater than that ia a solvent product. 

In the presence of the chelating agent and the insoluble salt, MX, pM of the solution is subject to both the metal buffering and the solubiUty equiUbria. Equating the right-hand sides of the equations 26 and 29 and rearranging gives... 

The aminopolycarboxylic acids are used principally as chelating agents, and a large proportion is used in water treatment and cleaning formulations. The data of Table 5 include nitnlotriacetic acid (NTA), most of which was exported. 

Textiles. Citric acid acts as a buffer in the manufacture of glyoxal resins which are used to give textiles a high quaUty durable-press finish (see Amino resins). It has been reported to increase the soil-release property of cotton with wrinkle-resistant finishes and is used as a buffer, a chelating agent, and a non-volatile acid to adjust pH in disperse dying operations (182—193). 

Polymers may act as weak chelating agents and thus retain hardness salts in solution in BW. In this event the hardness as determined by EDTA titration is measurable, particular attention should be given to maintaining the recommended level of carbonate or phosphate. In appropriate circumstances, chelating agents may be used in place of phosphate. 

The thermal dissociation of chelating agents and chelates of analytical interest. W. W. Wendlandt, Chelates Anal. Chem., 1967,1,107-143 (65). 

Wilson, A. D. Crisp, S. (1980). Dental cement containing poly(carboxylic acid), chelating agent and glass ionomer powder. US Patent 4,209,434. 

Treatment additives, chelating agents, and clay minerals can be added to a system to bind to metals and reduce metal mobility. Treatment additives, such as carbonates, phosphates, and hydroxides, form insoluble precipitates with metals, thus decreasing their bioavailability. Jonioh et al.141... 

Higher phytoextraction coefficients indicate higher metal uptake. The effectiveness of phytoextraction can be limited by the sorption of metals to soil particles and the low solubility of the metals however, metals can be solubilized through the addition of acids or chelating agents and so allow uptake of the contaminant by the plant. Ethylene diamine tetra-acetic acid (EDTA), citric acid, and ammonium nitrate have been reported to help in the solubilization of lead, uranium, and cesium... 

The book focuses on three main themes catalyst preparation and activation, reaction mechanism, and process-related topics. A panel of expert contributors discusses synthesis of catalysts, carbon nanomaterials, nitric oxide calcinations, the influence of carbon, catalytic performance issues, chelating agents, and Cu and alkali promoters. They also explore Co/silica catalysts, thermodynamic control, the Two Alpha model, co-feeding experiments, internal diffusion limitations. Fe-LTFT selectivity, and the effect of co-fed water. Lastly, the book examines cross-flow filtration, kinetic studies, reduction of CO emissions, syncrude, and low-temperature water-gas shift. 

Buckingham DA, Sargeson AM (1964) In Dwyer FP, Mellor DP (eds) Chelating agents and metal chelates. Academic, New York... 

Used industrially as a solvent to extract heavy metals, a gasoline additive, antifoam agent, plasticizer, chelating agent, and as a textile conditioner and antistatic agent. 

Usoni, L., Rinelli, G., and Marabini, A.M., Chelating Agents and Fuel Oil A New Way to Flotation, AIME General Annual Meeting. New York, USA 1971. 

Analysis of inorganic complexes. Valuable information has been arrived at by proper choice of a chelating agent and confirmation of the structure of complexes has been arrived. 

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