Fire Assay Litharge
Litharge, a reddish-orange lead oxide (PbO), is utilized in fire assays for gold and silver analysis. It exhibits light sensitivity and has a melting point of 888-890℃, boiling point of 1472℃ (decomposition), and a relative density of 9.53.
Qingdao Decent Labtech, a Chinese high-tech manufacturer, offers highly pure Litharge (Lead Oxide) for fire assay, catering to mineral laboratories with superior solutions.
Litharge, a specialized lead oxide, plays a crucial role in determining gold and silver through fire assay. This reddish-orange compound with the chemical formula PbO possesses exceptional purity.
Commonly known as C.I. 77577, C.I. Pigment Yellow 46, or Lead(II) oxide, Litharge has various English aliases such as Lead(II) oxide yellow, Lead(II)oxide 99%, Lead monoxide, and many more.
Physical Properties:
Litharge exists as yellow or reddish-yellow powder or small flaky crystals, susceptible to color changes when exposed to light. Its melting point ranges from 888 to 890℃, while boiling point occurs at 1472℃ (decomposition). The relative density of Litharge, in relation to water, is 9.53. It exhibits insolubility in water and ethanol but solubility in nitric acid, acetic acid, and hot lye.
Specifications:
PbO-05, a specific grade of Litharge, surpasses a purity level of 99.999%. The total impurity content, including silver, aluminum, arsenic, copper, cadmium, cobalt, iron, indium, magnesium, nickel, lead, and tin, is below 10ppm.
Structure:
Lead monoxide has two crystal forms: α-PbO (red crystal) and β-PbO (yellow crystal). α-PbO belongs to the tetragonal crystal system with a density of 9.35g/cm³, while β-PbO belongs to the orthorhombic crystal system with a density of 9.64g/cm³. β-PbO can be converted into α-PbO by boiling in water or by grinding at room temperature. Conversely, α-PbO converts into β-PbO at temperatures ranging from 475 to 583℃.
Usage:
• Litharge serves as a raw material for lead salts and polyvinyl chloride plastic stabilizers.
• It finds application in manufacturing high-refractive-index optical glass, ceramic enamel, and surface abrasives for precision machine tools.
• Electronic tubes, picture tubes, optical glass, X-ray-proof lead glass, and radiation-proof rubber products benefit from Litharge.
• Litharge is essential for chemical analysis, including the determination of gold and silver and precipitation of amino acids.
• It facilitates the preparation of soluble lead salts in lead plating and alloys, such as lead fluoroborate.
• The paint industry employs Litharge to produce lead soap for use in petroleum, rubber, glass, enamel, and related sectors.
Preparation:
Lead monoxide can be generated by heating lead, lead nitrate, lead sulfate, or lead sulfide in the presence of air. For example, the reaction between lead and oxygen yields 2 Pb + O2 → 2 PbO. High-purity Litharge is commonly obtained from lead acetate as a raw material, treated with concentrated ammonia water, and subsequently decomposed through heating.
Storage Method:
Store Litharge in a cool, well-ventilated warehouse, ensuring the temperature remains below 35℃ with a relative humidity below 80%. Seal the package and protect it from light. Avoid storing Litharge together with acids, alkalis, or edible chemicals. Adequate measures should be taken to contain potential leakages within the storage area.
Qingdao Decent Labtech is dedicated to delivering reliable and superior Litharge solutions, meeting the diverse needs of mineral laboratories worldwide.
