Name | 1-Naphthol |
Synonyms | Furro ER 1-naphtol 1-Naphthol a-Naphthol C.I. 76605 α-Maphthol 1-NAPHTHOL Fourrine 99 ALPHA NAPHTHOL 1-naphthalenol alpha-Naphthol 1-Naphthalenol Oxidation base 33 1-naphthol (alpha) Durafur developer D 1-Hydroxynaphthalene α-Hydroxynaphthalene C.I. Oxidation Base 33 1-napthol(alpha-napthol) |
CAS | 90-15-3 |
EINECS | 201-969-4 |
InChI | InChI=1/C10H8O/c11-10-7-3-5-8-4-1-2-6-9(8)10/h1-7,11H |
InChIKey | KJCVRFUGPWSIIH-UHFFFAOYSA-N |
Molecular Formula | C10H8O |
Molar Mass | 144.17 |
Density | 1.224 |
Melting Point | 94-96°C(lit.) |
Boling Point | 278-280°C(lit.) |
Flash Point | 125 °C |
Water Solubility | 436.7mg/L(25 ºC) |
Solubility | Soluble in alcohol, ether, benzene, chloroform and alkali solution, slightly soluble in water. |
Vapor Presure | 1 mm Hg ( 94 °C) |
Vapor Density | 4.5 (120 °C, vs air) |
Appearance | Colorless or yellow diamond crystal or powder |
Color | white to off-white |
Odor | Slight phenolic odor |
Maximum wavelength(λmax) | ['324nm(MeOH)(lit.)'] |
Merck | 14,6383 |
BRN | 1817321 |
pKa | 9.34(at 25℃) |
Storage Condition | Store below +30°C. |
Stability | Stable, but air and light sensitive - store under inert gas. Incompatible with strong bases, strong oxidizing agents. |
Sensitive | Air & Light Sensitive |
Explosive Limit | 5% |
Refractive Index | 1.6224 |
MDL | MFCD00003930 |
Physical and Chemical Properties | Properties: colorless or yellow rhomboid crystal or powder. There is an unpleasant smell of phenol.
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Use | Used as a basic raw material or intermediate for dyes, pesticides, spices and rubber antioxidants and color film couplers |
Risk Codes | R21/22 - Harmful in contact with skin and if swallowed. R37/38 - Irritating to respiratory system and skin. R41 - Risk of serious damage to eyes R51/53 - Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment. |
Safety Description | S22 - Do not breathe dust. S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S37/39 - Wear suitable gloves and eye/face protection S2 - Keep out of the reach of children. S61 - Avoid release to the environment. Refer to special instructions / safety data sheets. |
UN IDs | UN 2811 6.1/PG 3 |
WGK Germany | 1 |
RTECS | QL2800000 |
FLUKA BRAND F CODES | 8-23 |
TSCA | Yes |
HS Code | 29071510 |
Hazard Class | 6.1 |
Packing Group | III |
Toxicity | LD50 orally in Rabbit: 1870 mg/kg LD50 dermal Rabbit 880 mg/kg |
Downstream Products | 1-Hydroxy-2-naphthoic acid Napropamide (25%) Mordant Black T |
Reference Show more | Liu Sheng, Zheng Tian-yan, Gao Min, Hui Ai-ling, Zhang Wen-Cheng, Zhang Hua-wei, dubiao. Effects of different extraction methods on content and structural characteristics of okra pectin [J]. Modern Food Science and Technology 2019 35(03):161-168. |
LogP | 2.84 at 25℃ |
NIST chemical information | information provided by: webbook.nist.gov (external link) |
EPA chemical substance information | information provided by: ofmpeb.epa.gov (external link) |
naphthol | naphthol is a compound in which one hydrogen atom on the naphthalene ring is substituted with a hydroxyl group. There are two isomers of α-and β-naphthol, also called 1-naphthol and 2-naphthol. The molecular formula is C10H7OH, and the structural formula is shown in the figure. Both are white crystals. The α-isomer is acicular crystal with melting point of 96 ℃ and relative density of 1. 099 (99/4 ℃). Can be volatilized with water vapor, can also be sublimated. The β-isomer is orthorhombic crystals with a melting point of 123-124 °c and a density of 1.28g/cm3 (20 °c). Both are difficult to dissolve in water, soluble in ethanol, benzene, chloroform and other organic solvents. Dissolve in sodium hydroxide solution to generate the corresponding sodium salt of naphthol. Color reaction occurred in ferric chloride aqueous solution, α-isomer was purple, β-isomer was green. The sulfonation of naphthalene can be carried out at different temperatures. For example, α-Naphthalene sulfonic acid is mainly obtained by reacting with concentrated sulfuric acid at about 60 ℃, and β-Naphthalene sulfonic acid is mainly obtained by reacting at 160 ℃; then they were fused with sodium hydroxide to generate naphthol sodium salt, and finally acidified. They are flammable and irritant, inhalation of a large number of naphthol dust or vapor can lead to poisoning, symptoms of spasm, Vomit, Coma, etc. |
Use | used as analytical reagent, also used in organic synthesis synthetic rubber antioxidant, insecticide, perfume, dyes and so on 1-naphthol, also known as α-naphthol, naphthol, α-hydroxynaphthalene, is a key intermediate in the production of insecticide carbaryl. 1-naphthol is used in the dye industry to produce acid yellow 1, acid orange 20, mordant black 3, mordant black 11, Solvent Red 3, Solvent Orange 5, oil palm GB, etc, in the pharmaceutical industry can be used to manufacture preservatives and anti-corrosion drugs, etc., but also many aldehydes and mineral oil and vegetable oil effective antioxidant, widely used in synthetic fragrances, rubber anti-aging agent and color film coupler. The demand for 1-naphthol is roughly only about 5% of that of 2-naphthol. But 1-Naphthol as a raw material of insecticide carbaryl, demand is very big. The intermediates derived from 1-naphthol include N-phenyl -1-naphthylamine, N-ethyl -1-naphthylamine, N-cyclohexyl-1-naphthylamine, 1-hydroxy-2-naphthoic acid, 1-naphthol -2-sulfonic acid, 1-naphthol -4-sulfonic acid, 1,7-clexic acid, acetamido-7-naphthol, 2, 4-dinitronaphthol, etc. In the dye industry, acid yellow 1, acid orange 20, mordant black 3, mordant black 11, Solvent Red 3, Solvent Orange 5, oil palm GB, etc. The pharmaceutical industry can be used for the manufacture of preservatives and anti mild rheumatism drugs. It is also an effective antioxidant for many aldehydes and mineral and vegetable oils, and is widely used in synthetic perfumes, rubber antiaging agents and color formers for color film. Colorimetric Determination of titanium, niobium, tungsten, germanium, vanadium, nitrite and copper; Determination of tyrosine and protein; Used as dyes, pesticides, basic raw materials or intermediates of fragrances and rubber antioxidants and color film couplers |
production methods | 1-naphthol has a variety of production methods, can be divided into: Alpha-Naphthalene sulfonic acid alkali fusion method, Α-naphthylamine hydrolysis method, tetrahydronaphthalene method. 1. Α-naphthylamine hydrolysis method α-naphthylamine is hydrolyzed with dilute sulfuric acid as medium to obtain α-naphthol crude product, which is separated and neutralized and distilled to obtain finished product. 2. Sulfonation process refined naphthalene α-Naphthalene sulfonic acid is obtained by low-temperature sulfonation with sulfuric acid, and β-Naphthalene sulfonic acid is produced as by-product. After separation of by-products, neutralization, alkali fusion, acidification, separation and distillation are carried out to obtain the finished product. Raw material consumption quota: sulfuric acid (98%)900kg/t, refined naphthalene (99.5%)1150kg/t, caustic soda (42%)1300kg/t. There are several methods for the production of 1-naphthol. Α-Naphthalene sulfonic acid alkali fusion method using naphthalene as raw material, using concentrated sulfuric acid sulfonation at low temperature (below 40 ℃) to obtain α-Naphthalene sulfonic acid, then in 310~320 ℃ alkali fusion can be obtained 1-naphthol. The total yield of this method is about 40%, the by-product of 2-naphthol is more, and the consumption of acid and alkali is large. Using chlorosulfonic acid instead of concentrated sulfuric acid for sulfonation, O-nitroethylbenzene as solvent, and then alkali fusion can be obtained 1-naphthol, the yield is about 72%, The production of 2-naphthol is reduced, but the solvent is consumed. Α-naphthylamine hydrolysis method α-naphthylamine as raw material, hydrolysis in 15% ~ 20% sulfuric acid. The reaction temperature was 200 ℃ and the pressure was 1.2-1.5 MPa. The hydrolysis product was separated, the generated ammonium bisulfate was recovered, the content of 1-naphthol was 96% ~ 98% by neutralization and distillation, and the yield was nearly 90%. The process is simple, but the toxicity of α-naphthylamine is high, and the problems of equipment anti-corrosion and wastewater treatment are serious. If α-chloronaphthalene is used for hydrolysis, the conditions of temperature and pressure are higher, the reaction pressure is about 5MPa, and the reaction temperature is about 270 ℃, copper catalyst is required. The tetrahydronaphthalene method takes naphthalene as raw material, obtains tetrahydronaphthalene through hydrogenation, and then obtains 1-naphthol through oxidation and dehydrogenation. The hydrogenation of naphthalene to tetrahydronaphthalene adopts an industrial hydrogenation nickel molybdate catalyst and an "adiabatic" reaction device, with a pressure of about 3MPa, an average reaction temperature of 300 ℃ and a space velocity of 0.8 h-1, the ratio of hydrogen/naphthalene is 2500~6400 (volume ratio), the conversion rate of naphthalene per pass can reach 85%, the selection of tetralin can reach more than 92%, the purity of tetralin after rectification can reach more than 98%, and the total yield of hydrogenation and refining is 85.5%. Oxidation of tetralin to tetralone, Using multi-section bubble column continuous liquid phase oxidation, air as oxidant, atmospheric pressure operation, using chromium acetate and 2-methyl-5-ethylpyridine composite catalyst, reaction temperature 130 ℃, the molar ratio of tetralin to oxygen is 1: 0.6, and the residence time is 60~70min. The single-pass conversion rate of tetrahydronaphthalene was more than 20%, the selectivity to tetralone was about 90%, and the space-time yield of the reactor was more than 100g of tetralone (L · h). The product can obtain 98% tetralone by vacuum fractionation, and the unconverted tetralin can be recycled. The total yield of oxidation and product refining is 85.5% (based on tetralin). The dehydrogenation of tetralone to naphthol is a gas phase catalytic reaction at atmospheric pressure, using platinum/coarse pore silica gel (or platinum/activated alumina) catalyst and fixed bed reactor, the initial reaction temperature is 350 ℃, the space velocity of addition was 0.8 h-1, and the molar ratio of tetralone feed to hydrogen was 1: 3. The average conversion of tetralone dehydrogenation reaction is about 85%, the average yield is over 93%, the purity of refined naphthol is 98%, the total yield of dehydrogenation and product refining is 89.5% (based on tetralone). The total yield (including product refining) of naphthalene by hydrogenation, oxidation and dehydrogenation is 65.4%. The consumption quota of main raw materials for producing cresol per ton is 1.39 t of naphthalene and 600 of hydrogen. This method is the route adopted by large-scale production abroad at present, and has been continuously improved in recent years. It has the advantages of reasonable process, more advanced technology, easy access to raw materials (except naphthalene, mainly hydrogen and air), high product quality (basically does not contain β-isomer), low production cost, three waste less, the whole process is convenient for continuous and automatic control, suitable for large-scale production and other advantages, is a promising process route. |
spontaneous combustion temperature | 510°C |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |