Name | p-Cresol |
Synonyms | 4-cresol p-Kresol p-Cresol p-Toluol PARA-CRESOL KRESOL-PARA para cresol p-Oxytoluene p-Methyiphenol 4-Methylphenol phenol,-methyl- p-Tolyl alcohol 4-Hydroxytoluene p-Methylhydroxybenzene |
CAS | 106-44-5 |
EINECS | 203-398-6 |
InChI | InChI=1/C7H8O/c1-6-3-2-4-7(8)5-6/h2-5,8H,1H3 |
Molecular Formula | C7H8O |
Molar Mass | 108.14 |
Density | 1.034g/mLat 25°C(lit.) |
Melting Point | 32-34°C(lit.) |
Boling Point | 202°C(lit.) |
Flash Point | 193°F |
JECFA Number | 693 |
Water Solubility | 20 g/L (20 ºC) |
Solubility | 20g/l |
Vapor Presure | 1 mm Hg ( 20 °C) |
Vapor Density | 3.72 (vs air) |
Appearance | Crystalline Solid or Liquid |
Specific Gravity | 1.0341 (20/4℃) |
Color | Colorless to light yellow, may darken on exposure to light |
Exposure Limit | NIOSH REL: TWA 2.3 ppm (10 mg/m3), IDLH 250 ppm; OSHA PEL: TWA 5ppm (22 mg/m3); ACGIH TLV: TWA for all isomers 5 ppm (adopted). |
Merck | 14,2579 |
BRN | 1305151 |
pKa | 10.17(at 25℃) |
Storage Condition | Store below +30°C. |
Stability | Stable. Combustible. Incompatible with strong oxidizing agents. Air and light-sensitive. Hygroscopic. |
Sensitive | Light Sensitive |
Explosive Limit | 1%(V) |
Refractive Index | nD20 1.5395 |
Physical and Chemical Properties | This product is colorless transparent liquid or crystal, with phenol flavor, flammable. Soluble in ethanol, ether, chloroform and hot water, boiling point 202℃, melting point 35.26℃. |
Use | This product is the production of antioxidant 2, 6-di-tert-butyl-p-cresol and rubber antioxidant raw materials, at the same time, but also the production of pharmaceutical TMP and dyes available on the basis of important raw materials. |
Risk Codes | R24/25 - R34 - Causes burns R39/23/24/25 - R23/24/25 - Toxic by inhalation, in contact with skin and if swallowed. |
Safety Description | S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) S36/37 - Wear suitable protective clothing and gloves. |
UN IDs | UN 3455 6.1/PG 2 |
WGK Germany | 1 |
RTECS | GO6475000 |
FLUKA BRAND F CODES | 8 |
TSCA | Yes |
HS Code | 29071200 |
Hazard Note | Irritant |
Hazard Class | 6.1 |
Packing Group | II |
Toxicity | LD50 orally in rats: 1.8 g/kg (Deichmann, Witherup) |
Downstream Products | P-cresyl acetate P-cresyl phenylacetate |
FEMA | 2337 | P-CRESOL |
olfactory Threshold | 0.000054ppm |
Henry's Law Constant | 6.17 at 20.00 °C, 9.31 at 25.00 °C (dynamic equilibrium system-GC, Feigenbrugel et al., 2004a) |
LogP | 1.94 |
NIST chemical information | information provided by: webbook.nist.gov (external link) |
EPA chemical substance information | information provided by: ofmpeb.epa.gov (external link) |
toxicity | is toxic to the central nervous system and can cause death in severe cases. Ld501800 mg/kg (rat, oral). It is safe for use in food as a flavor (FDA,§ 172.515,2000). GRAS(FEMA). ▼▲ |
usage limit | FEMA(mg/kg): soft drinks 0.67; Cold drinks 0.01~1.0; candy and baked goods 0.01~2.0. |
Use | GB 2760-1996 specifies the permitted use of flavorants. bactericide. Fungicide. Organic Synthesis. used in organic synthesis This product is the raw material for the production of antioxidant 2, 6-di-tert-butyl-p-cresol and rubber antioxidant. Meanwhile, it is also the important basic raw material for the production of pharmaceutical TMP and dye-based Crestor sulfonic acid. p-cresol is an intermediate of the fungicide methyl phosphorus, the insecticide fenvalerate, and the ether, and is also an intermediate of the antioxidant additive 2, 6-di-tert-butyl-4-methylphenol and p-hydroxybenzaldehyde. raw materials for producing antioxidant 264(2, 6-di-tert-butyl-p-cresol) and rubber antioxidant. Phenolic resins and plasticizers can be made in the plastics industry. It is used as a disinfectant in medicine. In addition, it can also be used as raw materials for dyes and pesticides. |
production method | 1. Mixture of m-cresol the mother liquor after extracting m-cresol can be recrystallized by addition of oxalic acid. Toluene and sulfuric acid sulfonation, neutralization, the formation of sodium p-toluenesulfonate after alkali fusion, acidification, distillation to p-cresol product. In order to obtain high purity of p-cresol, there are two processes:(1) after rectification, the obtained P-cresol is separated by crystallization;(2) after sulfonation, the obtained P-toluenesulfonic acid is cooled, crystallized and filtered, then neutralization, alkali fusion, acidification, distillation to obtain the finished product. The sulfonated alkali melting technology developed by Nanjing Jinyan Chemical Corporation is mature, which can produce high purity p-cresol, change the process conditions, and use the device to produce m-cresol, O-cresol, phenol, naphthol and so on. There are several preparation methods. (1) toluene sulfonation alkali fusion method with toluene as raw material, sulfuric acid as sulfonating agent, sulfonation reaction at 110~130 ℃, after neutralization, alkali fusion reaction is carried out with molten sodium hydroxide at 340~365 ℃ to obtain sodium cresol. After acidification, crude cresol is obtained, and then O-cresol and phenol are separated by distillation, A p-cresol-based mixed cresol was obtained. The composition of isomers in the formation of cresol is determined by the temperature change, the type of sulfonating agent and the ratio of toluene and sulfonating agent. Nanjing Jinyan chemical corporation can produce high purity p-cresol by sulfonated alkali fusion method. Also commonly used sulfonating agent is fuming sulfuric acid, chlorosulfonic acid. Toluene sulfonation preparation of p-cresol is the earliest industrial method, this method process is mature, but need to consume a lot of acid, alkali, Equipment corrosion problem, the current method is the main method of production of p-cresol. The mother liquor after extraction of m-cresol from m-cresol and p-cresol mixture can be recrystallized by addition of oxalic acid. For example, the toluene solution after urea and filtration is heated to 95~100 ℃, oxalic acid is added under stirring for 2~3H, and then cooled at room temperature for about 16H, vacuum Filtration gave a white crystalline P-cresol oxalate complex. The complex is decomposed by hot water. After the upper oil layer is distilled by pressure distillation to toluene and water, the fraction of 93~0.094 ℃ is cut at 104 MPa to obtain p-Cresol with a purity of 95%. (2) P-toluidine diazonium hydrolysis of p-toluidine and sulfuric acid to generate p-toluidine sulfate, diazotization with sodium nitrite at 0~5 ℃, and then the diazonium salt is hydrolyzed in dilute sulfuric acid by heating, and the oily matter is separated out by steam, separate the oil layer into 1% sodium hydroxide, then decolorize and filter, add concentrated sulfuric acid to pH = 1, then separate the water layer, add zinc powder and sulfuric acid, then neutralize to Neutral with sodium carbonate, and separate the oily matter, it was washed with water and then distilled under reduced pressure to obtain a finished product. (3) separated from kerosene to get sulfonation of toluene with sulfuric acid to get p-toluenesulfonic acid, after cooling, crystallization, filtration, followed by neutralization with sodium sulfite to get p-toluenesulfonic acid, and then alkali fusion with sodium hydroxide, sodium p-cresol was obtained by acidification with sulfurous acid. Finally, it was separated by distillation and crystallization. |
category | corrosive article |
toxicity grade | high toxicity |
Acute toxicity | oral-rat LD50: 207 mg/kg; Oral-mouse LD50: 344 mg/kg |
stimulation data | Skin-rabbits 517 mg/24 h severe; eye-rabbit 103 mg severe |
explosive hazard characteristics | explosive when mixed with air; Corrosive to skin and cornea |
flammability hazard characteristics | flammable; Combustion-induced irritating smoke |
storage and transportation characteristics | The warehouse is ventilated and dried at low temperature; It is stored separately from the oxidant. |
fire extinguishing agent | Sand, foam, water mist |
Occupational Standard | TLV-TWA 5 PPM (22 mg/m3) |
spontaneous combustion temperature | 555°C |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |