What is cobalt aluminate? What is cobalt aluminate used for? What is the chemical formula for cobalt aluminate? Can Cobalt Aluminate substitute Cobalt Oxide

CoAl₂O₄  

Cobalt(II) aluminate - Cobalt Blue cobalt(2+);oxido(oxo)alumane. Bright blue ceramic CoAl2O4 nanocrystals was prepared by sol-gel technique using aluminum nitrate, cobalt nitrates, diethylene glycol monoethyl ether, and citric acid were used as precursor materials.

The basic cobalt blue color, Pigment Blue 28, is produced by high-temperature calcination of cobalt (II) oxide (CoO) and aluminum oxide (Al2O4). The variations are produced by a partial substitution of the cobalt by chromium and zinc, either alone or in combination with each other. The result is a large variety of cobalt blue pigments that differ in their tinting strength or hues (reddish or greenish blue), depending on the exact chemical composition. The lighter-colored cobalt blue is prepared by addition of zinc (II) oxide to the ingredients used for the basic pigment, forming Pigment Blue 72. Blue-green hues are produced by introducing chromium (III) oxide, partially replacing the aluminum (III) oxide in the basic cobalt blue, forming Pigment Blue 36.

All of them form the crystalline modification of spinel during calcination. The spinels are a class of minerals that crystallize in the cubic (isometric) crystal system with the oxide anions arranged in a cubic close-packed lattice and the cations occupy some or all of the octahedral and tetrahedral sites in the lattice. Spinel minerals form octahedral crystals that are usually twinned. They have an imperfect octahedral cleavage and conchoidal fracture. The hardness of spinel minerals is around 8 (chalk has a hardness of 2-3), specific gravity is 3.5-4.1 and it is transparent to opaque with a vitreous to dull luster.

Cobalt Aluminate - Uses in Pottery - Pigment Blue 28

Cobalt Aluminate Blue Spinel, an inorganic pigment, is a reaction product of high temperature calcination in which Cobalt (II) Oxide and Aluminum (III) Oxide in varying amounts are homogeneously and ionically interdiffused to form a crystalline matrix of spinel. Its composition may include any one or a combination of the modifiers Li2O, MgO, SiO2, TiO2, or ZnO. Mason Stain for tinting ceramic glazes, slip, and clay. Mason Stains are fritted lead-free oxides. They are safe and dependable to use.

Mason Stains are combinations of oxides, fritted to insure uniformity of color and thus insure uniformity of results in firing. They can be used to color transparent or opaque glazes, underglazes, slips, engobes or clay bodies. Color results will vary according to glaze composition, firing temperature and kiln atmosphere. The quantity of stain used will vary between 1%-15% depending on the depth of color required. The stains may also be used effectively as colorants for direct brush decoration when mixed with water and a flux such as Ferro Frit.

Cobalt aluminate, commonly known as cobalt blue, is an inorganic compound with the chemical formula CoAl₂O₄. It is a type of spinel, which is a mineral structure characterized by its cubic crystal system. Here are some key details about cobalt aluminate:

Properties:

• Appearance: Intense blue powder.
• Molecular Weight: 176.88 g/mol.
• Density: Approximately 3.97 g/cm³.
• Melting Point: About 1,350°C.
• Solubility: Insoluble in water; stable under normal conditions.

Chemical Behavior:

• Structure: Spinel structure with cobalt ions in the +2 oxidation state and aluminum ions in the +3 oxidation state.
• Stability: High thermal stability and resistance to chemical attack, which makes it suitable for high-temperature and harsh chemical environments.

Preparation:

Cobalt aluminate can be prepared by:

1. Solid-State Reaction: Mixing cobalt(II) oxide (CoO) and aluminum oxide (Al₂O₃) and then heating the mixture at high temperatures (around 1,200-1,400°C). $$\text{CoO} + \text{Al}_2\text{O}_3 \rightarrow \text{CoAl}_2\text{O}_4$$
2. Precipitation Method: Co-precipitating cobalt and aluminum salts followed by calcination at high temperatures to form the spinel structure.

Uses:

• Pigments: Widely used as a pigment in ceramics, glass, paints, and inks due to its vibrant blue color, which is stable under light and heat.
• Catalysts: Employed in catalytic processes, including oxidation reactions, due to its stability and activity.
• Coatings: Used in coatings to provide a durable and decorative finish.
• Art Materials: Popular in artist paints and materials because of its vivid and lasting blue color.

Safety and Handling:

• Toxicity: Cobalt compounds can be harmful if ingested, inhaled, or absorbed through the skin. While cobalt aluminate is generally considered less toxic than soluble cobalt salts, it is still advisable to handle it with care and use personal protective equipment.
• Environmental Impact: Cobalt mining and processing can have significant environmental impacts. Proper disposal and recycling are important to mitigate environmental risks.

Cobalt aluminate, with its brilliant blue color and excellent stability, is an important material in various industrial and artistic applications. However, like other cobalt compounds, it should be handled with appropriate safety precautions.

Formula: CoAl₂O₄
Molecular Weight: 176.89 g/mol
Form: powder
CAS Number: 1345-16-0
Density: 4.3 g/cm³
Synonyms: Cobalt Blue Liquid, cobalt(II) aluminate, Cobalt aluminum oxide, Cobalt aluminum oxide, nanopowder