Bismuth Oxychloride is a chemical compound, a synthetic dye. 

Chemical Name

• Bismuth chloride oxide

Composizione chimica e struttura

Chemical Composition and Structure

Bismuth Oxychloride is an inorganic compound with the chemical formula BiOCl. It consists of bismuth (Bi), chlorine (Cl), and oxygen (O), forming bismuth chloride oxide. This compound features a layered structure that contributes to its distinctive pearlescent appearance and optical properties.

Physical Properties

Bismuth Oxychloride typically appears as a fine white or slightly pearlescent powder. It has excellent chemical stability and resistance to light and heat, making it suitable for long-lasting applications. The pigment's layered structure gives it unique reflective and refractive properties, which enhance the brightness and luster of products.

Chemical Industrial Synthesis Process

• Preparation of reagents. The main raw materials include bismuth nitrate, sodium chloride, and sodium hydroxide.
• Synthesis of bismuth chloride. Bismuth nitrate is dissolved in distilled water. Sodium chloride is added to this solution to precipitate bismuth chloride.
• Filtration. The resulting suspension is filtered to separate the solid bismuth chloride from the aqueous solution.
• Preparation of bismuth hydroxide. The bismuth chloride is suspended in water and treated with sodium hydroxide to form bismuth hydroxide.
• Oxidation. The bismuth hydroxide is heated to decompose the water and form bismuth oxide.
• Chlorination. The bismuth oxide is treated with a sodium chloride solution under controlled conditions to form bismuth oxychloride (BiOCl).
• Filtration and washing. The BiOCl is filtered and washed with deionized water to remove any soluble impurities.
• Drying. The washed bismuth oxychloride is dried at controlled temperatures to remove residual moisture and obtain a dry powder.
• Grinding. The dried BiOCl is ground to obtain a fine and uniform powder.
• Stabilization. The Bismuth Oxychloride powder is stabilized to ensure its stability during transportation and storage, preventing aggregation and degradation.
• Quality control. The Bismuth Oxychloride undergoes rigorous quality testing to ensure it meets standards for purity and consistency. These tests include chemical analysis, spectroscopy, and physical tests to determine particle size and rheological properties.

What it is used for and where

Cosmetics - INCI Functions

Colorant. This ingredient has the function of colouring the solution in which it is inserted in a temporary, semi-permanent or permanent manner, either alone or in the presence of the complementary components added for colouring. Bismuth Oxychloride is widely used in cosmetic products such as eyeshadows, blushes, lipsticks, and powders. Its pearlescent effect adds a shimmering quality to makeup, enhancing visual appeal. It is also valued for its non-toxic nature and skin compatibility.

Restricted cosmetic ingredient as IV/123  a Relevant Item in the Annexes of the European Cosmetics Regulation 1223/2009.

Industrial Applications

Paints and Coatings: In the paint industry, bismuth chloride oxide is used to create special effects and high-gloss finishes. Its stability and reflective properties make it ideal for decorative applications.

Plastics and Polymers: This pigment is used to add pearlescence and enhance the visual appeal of plastic products. It provides uniform color and resists degradation from UV light and heat.

Ceramics and Glass: Bismuth Oxychloride is utilized in the production of ceramics and glass to achieve special optical effects and enhance the overall appearance of the finished products.

Inks: Bismuth chloride oxide is also used in printing inks to produce glossy and attractive finishes, ensuring stable and long-lasting colors.

Safety

Bismuth Oxychloride is generally considered safe for use in consumer products when handled according to standard safety procedures. It is non-toxic and environmentally stable. However, as with all fine powders, precautions should be taken to avoid inhalation and minimize direct contact with skin and eyes.

Studies

As an emerging nanomaterial,  (BiOCl) has attracted explosive interests in diverse areas. However, how it interfaces with biological systems, particularly its interaction with human cells and the resulting effects are completely unknown. In this paper, the cytotoxicity of BiOCl nanosheets (NSs) was investigated toward a human skin derived cell line (HaCaT). It was found that BiOCl-NSs had no cytotoxicity at low concentrations (1).

Bismuth oxychloride has been used as a photocatalyst due to its excellent absorption capacity towards the dyes or the aquatic pollutants present in the waste water. In summary, two adsorbents including BiOCl and Fe/BiOCl were prepared for the removal of cationic and anionic dyes with low concentration from the solutions. After grafting Fe3+ on the surface of BiOCl, the adsorbent showed more open porous structure and higher specific surface area. Both BiOCl and Fe/BiOCl are more favorable for removing the cationic dye molecules from the solution, whereas Fe/BiOCl displays higher adsorption capacity toward anionic dye molecules than BiOCl. Furthermore, BiOCl exhibited higher selective adsorption efficiency toward cationic dye molecules than Fe/BiOCl in mixed dye solutions. The prominent adsorption efficiency is probably to provide a potential application for as-prepared adsorbents in actual industrial wastewater (2).

Molecular Formula   BiClHO

Molecular Weight   261.44 g/mol

CAS    7787-59-9

EC number   232-122-7

UNII 4ZR792I587

Synonyms: 

Pigment White 14

Bismuth Oxychloride

Bismuth chloride oxide

CI 77163

References______________________________________________________________________

(1) Gao X, Zhang X, Wang Y, Wang Y, Peng S, Fan C. An in vitro study on the cytotoxicity of bismuth oxychloride nanosheets in human HaCaT keratinocytes. Food Chem Toxicol. 2015 Jun;80:52-61. doi: 10.1016/j.fct.2015.02.018. Epub 2015 Mar 6. PMID: 25754379.

(2) Zhao Q, Xing Y, Liu Z, Ouyang J, Du C. Synthesis and Characterization of Modified BiOCl and Their Application in Adsorption of Low-Concentration Dyes from Aqueous Solution. Nanoscale Res Lett. 2018 Mar 1;13(1):69. doi: 10.1186/s11671-018-2480-y. PMID: 29492698; PMCID: PMC5834949.