Anthraquinone CAS 84-65-1

What is Anthraquinone?

Anthraquinone (also known as 9,10-anthraquinone) is the oxidation product of anthracene at the 9 and 10 positions. It belongs to the fused-ring aromatic quinone class of compounds and is the basic parent nucleus of anthracene quinones. Its chemical formula is usually written as:

C14H8O2 (CAS No.: 84-65-1, molecular weight approximately 208.21)

Anthraquinone is a yellow or orange-yellow needle-like crystal at room temperature, with a melting point of approximately 284-286℃, a boiling point of approximately 376.8℃, a relative density of 1.438, a flash point of 185℃, and it can sublimate. Anthraquinone is soluble in organic solvents such as ethanol, ether, and acetone, but insoluble in water. It was first synthesized by Laurent in 1835 using nitric acid to oxidize anthracene. Industrial production routes such as gas-phase catalytic oxidation and the phthalic anhydride process were developed in the 20th century.

From a molecular structure perspective, anthraquinone molecules consist of three fused benzene rings, with a carbonyl group (C=O) at both positions 9 and 10, classifying them as quinone compounds. Their excellent chemical stability and reversible redox activity make them a core intermediate in dyes, papermaking, and hydrogen peroxide production . Furthermore, anthraquinones are widely found in nature—in plants such as rhubarb, aloe vera, and senna leaves—this dual identity as both an "industrial intermediate" and a "natural active ingredient" forms the structural and source basis for their application in scientific research.

Chemically, anthraquinones are stable and have reversible redox properties (anthraquinone/anthrahydroquinone redox couple), meaning they can be reduced to anthrahydroquinone and then oxidized back to their original state. Most of their derivatives are colored and resistant to light and heat.

Non-industrial grade anthraquinones refer to products intended for research and consumer applications, primarily including reagent-grade specifications. Compared to industrial grade, non-industrial grade products place greater emphasis on the following indicators:

Purity and Impurity Control

Research applications require stricter control over impurities and must meet relevant quality standards.

Melting point range

Melting point (approximately 284~286℃) is a classic indicator for judging purity, and it must meet the specified range.

Hue

The crystals should be yellow or orange-yellow with a pure color; abnormal color often indicates excessive impurities.

Solubility

It must be soluble in solvents such as ethanol, ether, and acetone, and the solution must be clear to ensure experimental preparation and synthetic applications.

What are the uses of Anthraquinone?

1. Dye intermediates (core application)

Anthraquinone is the core intermediate in the synthesis of anthraquinone dyes. Anthraquinone dyes (disperse dyes, acid dyes, vat dyes, reactive dyes, etc.) are a large class of organic dyes, second only to azo dyes in terms of variety and quantity. They are widely used in the dyeing and printing of textiles such as cotton, polyester, and wool, and are the pillar products of the dye industry.

2. Scientific research and laboratory applications (reagent grade)

Anthraquinones are commonly used organic reagents in the laboratory. Their reversible redox properties make them important model molecules in electrochemical, photochemical and coordination chemistry research, and they are also used in cutting-edge research on organic electrode materials (lithium batteries, sodium batteries) and functional dyes.

3. Applications in analytical chemistry

Anthraquinones and their derivatives can be used in analytical chemistry for colorimetric reactions and quantitative determination studies. High-purity anthraquinones can be used as standards and references for chromatographic analysis, serving testing laboratories and research institutions.

4. Natural dyes and cultural and creative products

Hydroxyanthraquinone natural dyes (such as alizarin) can be used in natural dyeing processes and the development of cultural and creative products, providing environmentally friendly natural color solutions for textile dyeing and artistic creation.

5. Teaching and Popular Science Experiments

The redox reactions of anthraquinones and quinone chemistry are topics taught in university organic chemistry courses. They can be used for classroom demonstrations and experimental teaching to help students understand the structure and properties of quinone compounds.

6. Papermaking cooking agents

Anthraquinones are used as catalysts in the sulfate and caustic soda pulping processes for papermaking. They can accelerate the delignification reaction, reduce the amount of alkali used, increase pulp yield, and shorten the pulping time. They are important additives in green pulping processes and are widely used in the papermaking industry.

7. Hydrogen peroxide production (anthraquinone process)

The anthraquinone process (using 2-ethylanthraquinone and other carriers as working carriers) is the mainstream process for producing hydrogen peroxide globally: the carrier is repeatedly used in hydrogenation, oxidation, and extraction cycles to produce high-concentration hydrogen peroxide, which is supplied to industries such as bleaching, disinfection, and chemicals. Anthraquinone is therefore at the core of the hydrogen peroxide industry chain.

8. Organic synthesis intermediates

Anthraquinones and their derivatives are synthetic intermediates for a variety of fine chemicals, used in the preparation of photosensitive materials, functional dyes, and electronic chemicals.

9. Batteries and new energy products (indirect contact)

Anthraquinone compounds are a research hotspot in novel organic electrode materials. Future energy storage batteries may use anthraquinone-based materials, and the industrial chain of new energy products is related to anthraquinone.

Summarize

Anthraquinone (9,10-anthraquinone) is a yellow, needle-like crystalline fused-ring quinone compound, a star intermediate in the dye, paper, and hydrogen peroxide industries. In daily life, we indirectly encounter it through the supply chains of dyed clothing, paper products, hydrogen peroxide disinfection and bleaching products, traditional Chinese medicine, natural dyes, and new energy products. In non-industrial applications, reagent-grade anthraquinone is widely used in organic synthesis and electrochemical research, analytical chemistry, natural dye cultural and creative products, and teaching experiments, making it an important fused-ring compound bridging "daily use" and "scientific research and cultural and creative industries."