Bismuth oxychloride

Bismuth oxychloride is produced by the hydrolysis of very acidic (pH 1.0) bismuth solutions in the presence of chloride. The crystal quahty can be varied by 

The low Ught stabiUty, the fast settling caused by the high density of 7.73 g/cm and the lack of mechanical stability hmit the use of BiOCl in technical appUca-tions. Therefore, it is mainly used in cosmetics, but also in buttons and jewelry. 

The hght stability can be improved to some extent by cerium doping and UV absorbers. 

Currently, use of basic lead carbonate is limited to artificial pearls, buttons, and bijouterie. Due to the low chemical stability of this pigment and toxicity problems, it is being increasingly replaced by bismuth oxychloride and mica-based pigments. Worldwide production of basic lead carbonate pigment in 1995 was ca. 10001. 

Powders containing bismuth compounds have long been used for decorative purposes to generate a shiny luster or lustrous colors (e.g., facial cosmetic powder in ancient Egypt, imitation pearls made by coating glass and ceramic beads). Bismuth oxychloride [7787-59-9], BiOCl, Mr 260.4, was the first synthetic nontoxic nacreous pigment. It is produced by hydrolysis of acidic bismuth solutions in the presence of chloride ions. Precipitation conditions may be varied (concentration, temperature, 

Pure BiOCl is available in three grades with different nacreous effects that depend on the aspect ratios and crystal size  

1) Low- or medium-luster powder (aspect ratio 1 10 to 1 15), mainly used as a highly compressible, white, lustrous filler with excellent skin feel 

2) Dispersion of high luster quality (aspect ratio 1 20 to 1 40) consisting of square or octagonal platelets in nitro-cellulose lacquers (nail polish) or castor oil (lipsticks) 

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Recovery of Bismuth from Tin Concentrates. Bismuth is leached from roasted tin concentrates and other bismuth-beating materials by means of hydrochloric acid. The acid leach Hquor is clarified by settling or filtration, and the bismuth is precipitated as bismuth oxychloride [7787-59-9] BiOCl, when the Hquors are diluted usiag large volumes of water. The impure bismuth oxychloride is usually redissolved ia hydrochloric acid and reprecipitated by diluting several times. It is then dried, mixed with soda ash and carbon, and reduced to metal. The wet bismuth oxychloride may also be reduced to metal by means of iron or 2iac ia the presence of hydrochloric acid. The metallic bismuth produced by the oxychloride method requites additional refining. 

Bismuth oxychloride [7787-59-9]—Cl Pigment White 14, Cl No. 77163. A synthetically prepared white or nearly white amorphous or finely crystalline, odorless powder consisting principally of BiOCl. Bismuth oxychloride is synthetic pearl essence. It is used in Upstick, nail poHsh, eye makeup, and other cosmetics to produce a lustrous, pearly effect. 

Tsunogai and Nozaki [6] analysed Pacific Oceans surface water by consecutive coprecipitations of polonium with calcium carbonate and bismuth oxychloride after addition of lead and bismuth carriers to acidified seawater samples. After concentration, polonium was spontaneously deposited onto silver planchets. Quantitative recoveries of polonium were assumed at the extraction steps and plating step. Shannon et al. [7], who analysed surface water from the Atlantic Ocean near the tip of South Africa, extracted polonium from acidified samples as the ammonium pyrrolidine dithiocarbamate complex into methyl isobutyl ketone. They also autoplated polonium onto silver counting disks. An average efficiency of 92% was assigned to their procedure after calibration with 210Po-210Pb tracer experiments. 

Bismuthonium ylides, 4 34 Bismuth(III) oxide, 4 23-24 Bismuth oxide(l l), 4 23 Bismuth oxide(l 2), 4 23 Bismuth oxide(2 4), 4 23 Bismuth oxide(3 5), 4 23 Bismuth oxide(4 9), 4 23 Bismuth oxide halides, 4 23 Bismuth oxides, 4 23-24 Bismuth oxybromide, 4 23 Bismuth oxychloride, 4 23 physical properties of, 4 20t pigment used in makeups, 7 836t Bismuth oxyfluoride, 4 23 Bismuth oxyiodide, 4 23 Bismuth pentafluoride, 4 22 physical properties of, 4 20t Bismuth phosphate, 4 25... 

Bi(N03)3 forms bismuth oxychloride, BiOCl in dilute nitric acid solution, upon addition of sodium chloride. 

Bismuth oxychloride is used in face powder and other cosmetics. It also is used in pigments dry-ceU cathodes to make artificial pearls and in medicines. 

Bismuth oxychloride is made hy treating bismuth chloride with water and then drying the white precipitate so formed to expel a molecule of water ... 

Compound Name Barium Peroxide Bismuth Oxychloride Zirconium Oxychloride Sulfuric Acid Benzene Hexachloride Oil Spindle Sucrose... 

Bismuth Chloride Oxide Bismuth Oxychloride Bismuth Subchloride Bismuthyl Chloride Bisphenol A... 

Table 52 contains a comparative overview of Ti02-mica, basic lead carbonate, bismuth oxychloride, and natural fish silver pigments. Some further physical data are summarized in Table 53. 

New Developments Based on Non-Micaceous Systems. The class of single crystal lustrous pigments is not limited to the non-absorbing types like bismuth oxychloride and basic lead carbonate. Recent developments are absorbing pigments such as platelet-like graphite, laminar phthalocyanines and flaky iron oxides. These flakes... 

Some of tlie salts of bismuth are used in medicines for the relief of digestive disorders because of the smooth, protective coating the compounds impart to imtated mucous membranes. Like barium, bismuth also is used as an aid in x-ray diagnostic procedures because of its opacity to x-rays. At one time, certain bismuth compounds were used in the treatment of syphilis. Bismuth oxychloride, which is pcarlcsccnt, has found use in cosmetics, imparting a frosty appearance to nail polish, eye shadow, and lipstick, but may be subject to increasing controls. Bismuth phosphomolybdate has been used as a catalyst in the production of acrylonitrile for use in synthetic fibers and paints. Bismuth oxide and subcarbonate are used as fire retardants for plastics. 

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