NAPHTHALENE (TAR CAMPHOR)

NAPHTHALENE

PRODUCT IDENTIFICATION

CAS NO.

91-20-3

NAPHTHALENE

EINECS NO.

202-049-5

FORMULA

C₁₀H₈

MOL WT.

128.16

H.S. CODE

TOXICITY

Oral rat LD50: 490 mg/kg

SYNONYMS

Naphthalin; Naphthaline; Moth balls; Naftalen;

Coal tar camphor; Tar camphor; Naphthalin; White tar; Moth; Albocarbon; Dezodorator;

DERIVATION

CLASSIFICATION

PHYSICAL AND CHEMICAL PROPERTIES

PHYSICAL STATE

white solid

MELTING POINT

79 - 82 C

BOILING POINT

217 - 218 C

SPECIFIC GRAVITY

0.99

SOLUBILITY IN WATER

Insoluble (3mg/100ml)

VAPOR DENSITY

4.4

AUTOIGNITION

567 C

NFPA RATINGS

Health: 2; Flammability: 2; Reactivity: 0

REFRACTIVE INDEX

FLASH POINT

79 C

STABILITY

Stable under ordinary conditions. Hygroscopic.

GENERAL DESCRIPTION & APPLICATIONS

Naphthalene is a white, volatile aromatic hydrocarbon with characteristic odor; insoluble in water, somewhat soluble in methanol/ethanol, soluble in organic solvents and very soluble in ether, chloroform, or carbon disulfide. Commercially it is available in molten form or in flaked form. It has the molecular structure of two fused or condensed benzene rings sharing two adjacent carbon atoms; C₁₀H₈. Naphthalene is obtained from coal tar which is distilled in the temperature range of 170 - 230 C and is treated with a sodium hydroxide solution to remove phenols. Naphthalene is obtained by the isolation from pyrolysis residue oils, olefin fractions, and petroleum-derived fractions. The distribution capacity is supposed to be about 60% coal-tar and 40% petroleum-derived naphthalene in U.S.A. It is an important parent material to produce numerous substitution products used in the manufacture of dyes, insecticides, organic solvents and synthetic resins. Phthalic anhydride is prepared by oxidizing naphthalene to be used in the manufacture of dyes, resins, plasticizers, and insecticides. Naphthalene sulfonate surfactants and dispersants, however, have increased their market share significantly and are expected to drive whatever growth there is for naphthalene. Naphthalene is the major raw material for Carbaryl, used as a general-purpose insecticide. Naphthalene is also used for moth repellents, fungicides, lubricants, explosives, wood preservatives, vermicides and hydronaphthalenes (tetralin, decalin). Hydronaphthalenes are used for major raw material for dyes, resins, plasticizers, and insecticides. They are also used in reactive and process solvents, heat transfer fluid, dye carrier, fuel additives, lubricants, ore flotation and oilfield chemicals.

SALES SPECIFICATION

APPEARANCE

brown flake

PURITY

95.0 % min (JIS K 2436)

NON-VOLATILES

0.3 % max (JIS K 2436)

ASH

0.1% max (JIS K 2436)

FREEZING POINT

77.5 min (JIS K 2436)

SULFUR CONTENT

0.7 % max (ASTM D 129-91)

TRANSPORTATION

PACKING

HAZARD CLASS

4.1 (Packing Group: III)

UN NO.

1334

OTHER INFORMATION

Hazard Symbols: XN N, Risk Phrases: 22-50/53, Safety Phrases: 36/37-60-61

GENERAL DESCRIPTION OF PAHs

Polycyclic aromatic hydrocarbons (also called polynuclear hydrocarbons) have two or more single or fused aromatic rings if a pair of carbon atoms is shared between rings in their molecules. In particular, the term 'PAH' refers to the compounds consisting of only carbon and hydrogen atoms while the wider term 'polycyclic aromatic compounds' includes the alkyl-substituted derivatives and functional derivatives such as nitro- and hydroxy-PAH as well as the heterocyclic analogues, which contain one or more hetero atoms in the aromatic structure. PAHs exist in various combinations that manifest various functions such as light sensitivity, heat resistance, conductivity, emittability, corrosion resistance and physiological action. The simplest examples are naphthalene having two benzene rings side by side and biphenyl having two bond-connected benzene rings. PAHs are not found in synthetic products and are non-essential for the growth of living cells. The general characteristics of PAH describe high melting- and boiling-points (they are solid), low vapour pressure, and very low water solubility, decreasing with increasing molecular weight whereas resistance to oxidation, reduction, and vapourization increases. Vapour pressure tends to decrease with increasing molecular weight. PAHs are highly lipophilic and readily soluble in organic solvents. The lower molecular weight PAHs of 2 or 3 ring groups such as naphthalenes, fluorenes, phenanthrenes, and anthracenes have toxicity which tends to decrease with increasing molecular weight. PAHs are not synthesized chemically for industrial purposes but are isolated from concentrated coal-tar products (or from pyrolysis of coal hydrocarbons) followed by subsequent purification through repeated distillation and crystallization. Some PAHs such as naphthalene are also obtained from the concentration of the high boiling residual oil (and asphalt) derived from crude petroleum refinery processing. These PAHs are mostly used as intermediaries in pharmaceuticals, agricultural products, photographic products, thermosetting plastics, lubricating materials, and other chemical industries. General uses are;

Acenaphthene: Intermediate for naphthalic acids, naphthalic anhydride (intermediate for pigments) and for acenaphthylene (intermediate for resins); Intermediate for dyes, soaps, pigments, pharmaceuticals, insecticide, fungicide, herbicide and plant growth hormones. It is used to manufacture plastics and as an agent for inducing polyploidy.
Acridine: Dye and pharmaceutical manufacturing
Anthracene: Its oxidation yields anthraquinone, the parent substance of a large class of dyes and pigments; .diluent for wood preservatives; scintillant (for detection of high-energy radiation)
Fluoranthene: manufacturing fluorescent and vat dyes, pharmaceuticals and agrochemicals.
Fluorene: basic subsance for production of dyes, pigments, pesticides, thermoset plstic and pharmaceuticals; manufacturing fluorenone (mild oxidizing agent)
Naphthalene: In the production of phthalic anhydride, carbaryl insecticide, beta-naphthol, tanning agents, moth repellent, and surfactants - naphthalene: main use: production of phthalic anhydride (intermediate for polyvinyl chloride plasticizers); also, production of azo dyes, surfactants and dispersants, tanning agents, carbaryl (insecticide), alkylnaphthalene solvents (for carbonless copy paper), and use without processing as a fumigant (moth repellent)
Phenanthrene: manufacturing phenanthrenequinone (intermediate for pesticides); manufacturing diphenic acid (intermediate for resins)
Pyrene: manufacturing perinon pigments
Quinoline: solvent for resins & terpines; decarboxylation agent; parent compound to make drugs, fungicides, biocides, alkaloids, dyes, rubber chemicals and flavoring agents

Precise PAHs, specific refined products are used also in the field of electronics, functional plastics and liquid crystals. Pharmaceutical and agricultural PAHs obtained coal tar are such materials as indole, indolizine, indene, quinoline, quinalidine, isoquinoline and their derivatives. High boiling-point special solvent are such materials as tetoralin, decaline, methyl-naphthalenes. Coumarins and dihydrocoumarins which can be obtained coal tar are PAHs used in perfumery. Thermosensitive paper sensitizer PAHs are such materials as p-benzylbiphenyl and ethylbiphenyl.

EXAMPLES OF PAH PARENT COMPOUNDS

PENTALENE	INDENE (CAS RN: 95-13-6)

NAPHTHALENE (CAS RN: 91-20-3)	AZULENE (CAS RN: 275-51-4)

HEPTALENE	BIPHENYLENE (CAS RN: 259-79-0)

as-INDACENE	s-INDACENE

ACENAPHTHALENE (CAS RN: 83-32-9)	FLUORENE (CAS RN: 86-73-7)

PHENALENE (CAS RN: 203-80-5)	ANTHRACENE (CAS RN:120-12-7)

FLUORANTHENE (CAS RN: 206-44-0)	ACEPHENANTHRYLENE

TRIPHENYLENE (CAS RN: 217-59-4)	PYRENE (CAS RN: 129-00-0)

CHRYSENE (CAS RN: 218-01-9)	NAPHTHACENE (CAS RN: 92-24-0)

PLEIADENE (CAS RN: )	PICENE (CAS RN: 213-46-7)

PERYLENE (CAS RN: 198-55-0)	PENTAPHENE (CAS RN: 222-93-5)

PENTACENE (CAS RN: 135-48-8)	TETRAPHENYLENE (CAS RN: 212-74-8)

RUBICENE (CAS RN: 197-61-5)	CORONENE (CAS RN: 191-07-1)

PYRANTHRENE (CAS RN: 191-13-9)	OVALENE (CAS RN:190-26-1)