Properties antimony solubility

It is surprising that the confusion over fundamental solid state properties such as phase composition and cationic oxidation states should have remained unclarified for so long, and it is disturbing that so many contradictory results and interpretations have been reported from supposedly similar materials. The lack of unanimity over the extent of antimony solubility in tin(IV) oxide is particularly surprising since many workers 9-11, 23, 25) have suggested that the formation of a solid solution is an important factor in the catalytic character of these materials. Hence, it is clear from these early studies that the extent and conditions for solid solution formation are completely uncertain. 

Both antimony tribromide and antimony ttiiodide are prepared by reaction of the elements. Their chemistry is similar to that of SbCl in that they readily hydroly2e, form complex haUde ions, and form a wide variety of adducts with ethers, aldehydes, mercaptans, etc. They are soluble in carbon disulfide, acetone, and chloroform. There has been considerable interest in the compounds antimony bromide sulfide [14794-85-5] antimony iodide sulfide [13868-38-1] ISSb, and antimony iodide selenide [15513-79-8] with respect to their soHd-state properties, ferroelectricity, pyroelectricity, photoconduction, and dielectric polarization. 

Tinplate and Solder. Metallurgical studies were performed to determine the effect of irradiation at low temperature on the corrosion resistance of tinplate and on the mechanical properties and microstructure of tinplate and side-seam solder of the tinplate container. The area of major interest was the effect of low-temperature irradiation on the possible conversion of the tin from the beta form to the alpha form. In the case of pure tin, the transition occurs at 18 °C. It was feared that low-temperature irradiation would create dislocations in the crystal lattice of tin and enhance the conversion of tin from the silvery form to a powdery form rendering the tin coating ineffective in protecting the base steel. Tin used for industrial consumption contains trace amounts of soluble impurities of lead and antimony to retard this conversion for several years. 

Lead and Alloys Chemical leads of 99.9 percent purity are used primarily in the chemical industry in environments that form thin, insoluble, and self-repairable protective films, e.g., salts such as sulfates, carbonates, or phosphates. More soluble films such as nitrates, acetates, or chlorides offer little protection. Alloys of antimony, tin, and arsenic offer limited improvement in mechanical properties, but the usefulness of lead is limited primarily because of its poor structural qualities. It has a low melting point and tensile stress as low as 1 MPa (145 Ibf/in ). 

The use of polyols such as pentaerythritol, mannitol, or sorbitol as classical char formers in intumescent formulations for thermoplastics is associated with migration and water solubility problems. Moreover, these additives are often not compatible with the polymeric matrix and the mechanical properties of the formulations are then very poor. Those problems can be solved (at least partially) by the synthesis of additives that concentrate the three intumescent FR elements in one material, as suggested by the pioneering work of Halpern.29 b-MAP (4) (melamine salt of 3,9-dihydroxy-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5,5]-undecane-3,9-dioxide) and Melabis (5) (melamine salt of bis(l-oxo-2,6,7-trioxa-l-phosphabicyclo[2.2.2]octan-4-ylmethanol)phosphate) were synthesized from pentaerythritol (2), melamine (3), and phosphoryl trichloride (1) (Figure 6.4). They were found to be more effective to fire retard PP than standard halogen-antimony FR. 

Pure lead has low creep and fatigue resistance, but its physical properties can be improved by the addition of small amounts of silver, copper, antimony, or tellurium. Lead-clad equipment is in common use in many chemical plants. The excellent corrosion-resistance properties of lead are caused by the formation of protective surface coatings. If the coating is one of the highly insoluble lead salts, such as sulfate, carbonate, or phosphate, good corrosion resistance is obtained. Little protection is offered, however, if the coating is a soluble salt, such as nitrate, acetate, or chloride. As a result, lead shows good resistance to sufuric acid and phosphoric acid, but it is susceptible to attack by acetic acid and nitric acid. 

Properties Colorless, transparent, very hygroscopic, crystalline mass. Fumes slightly in air. D 3.14, bp 223.6C, mp 73.2C. Soluble in alcohol, acetone, acids. With water forms antimony oxychloride. 

Antimony compounds are based on antimony, an element that exhibits both metal and nonmetal properties. Many of its compounds are toxic and corrosive, particularly the soluble salts. They include antimony iodide and antimony perchloride. Some antimony compounds decompose in water to produce toxic gases e.g., antimony sulphate decomposes to sulphur dioxide while antimony bromide produces bromine gas. 

A juxtaposition of the data in Fig. 4.9 with the equilibrium phase diagram of the Pb—Sb system presented in Fig. 4.3 indicates that, at 252 °C and up to 3.5 wt% loading level in the alloy, antimony has the highest solubility in a-Pb dendrites. On cooling, the dendrites get oversaturated with Sb and reorganisation of the structure of the solid phases starts, whereby the content of Sb in the a-Pb dendrites diminishes to 0.1% at room temperature. This improves the mechanical properties of the alloys. At Sb content between 3.0 and 11 wt%, the amount of the eutectic phase in the alloys changes but slightly, which results in minor improvement of their mechanical properties. 

It seems that only alloys with particular properties are suitable for casting grids for lead—acid batteries. Lead—calcium alloys, similar to lead—antimony alloys, belong to the age-hardening or precipitation-hardening group of alloys. With decrease of temperature, the solubility of calcium in the a-Pb solid—solution decreases and it precipitates in the form of small Pb3Ca particles. A similar picture was described earlier for the Pb—Sb alloys. 

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