Acid Orange 7 Property

Melting point:

164°C

Density 

1.525[at 20℃]

vapor pressure 

0Pa at 25℃

storage temp. 

Amber Vial, -20°C Freezer, Under inert atmosphere

solubility 

Very soluble in water; very slightly soluble in ethanol

pka

8.26, 11.4(at 25℃)

Colour Index 

15510

form 

Crystalline Powder

color 

Green to blue

PH Range

Amber (7.4) to orange (8.6);Orange (10.2) to red (11.8)

Odor

Odorless

Water Solubility 

116 g/L (30 ºC)

λmax

483nm

Merck 

14,6858

BRN 

3898201

Stability:

Light Sensitive

Biological Applications

Cosmetics; wound dressing materials

Major Application

Organic light emitting diodes (OLEDs), nanoparticles, inks, wood preservatives, textiles, hair dyes, cosmetics, wound dressing materials, biofuel cells

LogP

-0.95 at 20℃

CAS DataBase Reference

633-96-5(CAS DataBase Reference)

EPA Substance Registry System

C.I. Acid Orange 7, monosodium salt (633-96-5)

Safety

Hazard Codes 

Xi

Risk Statements 

36/37/38

Safety Statements 

26-36-37/39

WGK Germany 

3

RTECS 

DB7084000

HS Code 

32041200

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

Precautionary statements

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P280Wear protective gloves/protective clothing/eye protection/face protection.

Acid Orange 7 Chemical Properties,Usage,Production

Chemical Properties

Orange-red powder

Uses

Acid Orange 7 (CAS# 633-96-5) is an environmental pollutant.

Definition

ChEBI: Acid orange 7 is a member of naphthalenes. Orange allergenic extract is used in allergenic testing.

Preparation

Acid Orange 7, commonly known as acidic orange II. 4-Aminobenzenesulfonic acid diazo, and Naphthalen-2-ol coupling. It is produced by azo coupling of β-naphthol and diazonium derivative of sulfanilic acid.

Flammability and Explosibility

Non flammable

Properties and Applications

red light orange. Golden yellow powder. Soluble in water is red light yellow, orange soluble in alcohol. The strong sulfuric acid for quality in red, dilute create tan precipitation; In a golden of nitric acid; In the thick of sodium hydroxide solution not dissolve. Its water solution with hydrochloric acid generation tan precipitation; Add sodium hydroxide solution brown. In dyeing copper ions trend dark red in colour and lustre of iron ion shallow and dark. Discharge the gender is good. Mainly used for silk and wool dyeing, widely used in wool dyeing, can be used for wool, silk and polyamide fiber fabric of direct printing, leather and paper color, can also be used in indicator and biological shading. Is tasted can be used as a food dye, heavy metal salt used in organic pigments.

Purification Methods

Purification is as for Orange I. Its solubility in H2O is 40g/L at 25o. [Müller et al. Helv Chim Acta 35 2579 1952.] Also purify it by extracting it with a small volume of cold water, then crystallising it by dissolving in boiling water, cooling to ca 80o, adding two volumes of EtOH and cooling. When cold, the precipitate is filtered off, washed with a little EtOH and dried in air. It can be salted out from aqueous solution with sodium acetate, then repeatedly extracted with EtOH. Meggy and Sims [J Chem Soc 2940 1956], after crystallising the sodium salt twice from water, dissolved it in cold water (11mL/g) and added conc HCl to precipitate the acid dye which was separated by centrifugation, redissolved and again precipitated with acid. After washing the precipitate three times with 0.5M acid, it was dried over NaOH, recrystallised twice from absolute EtOH, washed with a little Et2O, dried over NaOH and stored over conc H2SO4 in the dark. It can then be converted to the pure salt with the calculated amount of NaOH or Na2CO3. [Beilstein 16 IV 408.]