مرجع مواد شیمیایی ایران
اطلاعات عمومی بوتیل هیدروکسی تولوئن
  • نام شیمیایی

    • بوتیل هیدروکسی تولوئن

    • Butylated hydroxytoluene

  • مترادف ها
    • 2,6-Di-tert-butyl-4-methylphenol ; 2,6-Di-tert-butyl-p-cresol ; 3,5-Di-tert-butyl-4-hydroxytoluene ; DBPC ; BHT ; E321 ; AO-29 ; Avox BHT ; Additin RC 7110 ; Dibutylated hydroxytoluene ; 4-Methyl-2,6-di-tert-butyl phenol

  • CAS
    128-37-0
  • فرمول مولکولی
    C15H24O
  • جرم مولکولی
    220/35
  • EINECS
    204-881-4
  • ICB Number
    ICB 5880
  • شکل و حالت فیزیکی
    پودر سفید - زرد روشن
  • نقطه ذوب
    69-72 °C
  • نقطه جوش
    265 °C
  • دانسیته
    1/048 g/cm3
  • فشار بخار
    0/01 mmHg (20°C)
  • ضریب شکست (n20/D­­)
    1/4859
  • نقطه اشتعال
    127 °C
  • دمای نگهداری
    0-6 °C
  • حلالیت در آب
    نامحلول در آب
  • شماره CAS
    128-37-0
  • شماره ثبت تجاری (RBN)
    1911640
  • شماره مرک (Merck)
    14,1548
  • NIST Chemistry Reference
  • EPA Substance Registry System
  • مراجع MSDS
  • ارائه دهنده
    زبان
  • انگلیسی
  • Chemical Properties
    • white crystalline solid

  • Air & Water Reactions
    • Insoluble in water.

  • Reactivity Profile

    Phenols, such as 2,6-Di-tert-butyl-4-methylphenol, do not behave as organic alcohols, as one might guess from the presence of a hydroxyl (-OH) group in their structure. Instead, they react as weak organic acids. Phenols and cresols are much weaker as acids than common carboxylic acids (phenol has Ka = 1.3 x 10^[-10]). These materials are incompatible with strong reducing substances such as hydrides, nitrides, alkali metals, and sulfides. Flammable gas (H2) is often generated, and the heat of the reaction may ignite the gas. Heat is also generated by the acid-base reaction between phenols and bases. Such heating may initiate polymerization of the organic compound. Phenols are sulfonated very readily (for example, by concentrated sulfuric acid at room temperature). The reactions generate heat. Phenols are also nitrated very rapidly, even by dilute nitric acid. Nitrated phenols often explode when heated. Many of them form metal salts that tend toward detonation by rather mild shock. May react with oxidizing materials.

  • Synthesis
    • 1.Industrially, BHT is prepared by the reaction of p-cresol (4-methylphenol) with isobutylene (2-methylpropene) catalyzed by sulfuric acid: CH3(C6H4)OH + 2 CH2=C(CH3)2 → ((CH3)3C)2CH3C6H2OH Isobutene is added in the (98:2) mixture of p-cresol and concentrated sulfuric acid. The reaction is carried out at 65~70 ℃ for 5h. The acid in the mixture is washed away with water of 60 ℃. The mixture is then washed with 10% NaOH solution and hot water to obtain the neutral crude product. The crude product is dissolved in hot 50% alcohol along with 0.5% of sulfocarbamide. Filtration and spin-drying is carried out when the liquid is still hot. The finished product is obtained through the following desiccation. In this routine, the productivity rate is as high as and the product purity is with melting point of over 69.5℃. In industry, the cascading main-vice tower technology is usually adapted. P-cresol and catalysts are put in the main and vice towers. The temperature in the main tower is maintained at 6580℃ while that in the vice tower at 5070℃. Isobutene gas is pumped in from the bottom, the majority of which react with p-cresol and the rest of which is let into the vice tower for further reaction with p-cresol. The reaction cycle in the main tower lasts for 45h. On the end of the reaction, isobutene gas is cut off and NaOH solution (20%) is added. Compressed air is pumped in to bubble the solution. The neutralized crude alkylation product is extracted through distillation tower with 8 theoretical plates. The crude product is then dissolved in 95% alcohol and separated from mineral salts using ion exchange followed by refrigeration crystallization at 1020℃, separation and vacuum drying to obtain the finished product with its melting point at over 69℃. 2.In another synthesis routine, p-cresol and tert.-butyl alcohol are mixed in their molar ratio of 11.1. Under the catalysis of ortho-phosphoric acid, the react is conducted at 6570℃ with intense stirring. The product is washed with caustic soda solution to reach certain basicity and then washed into neutral with water. The dissolvent is then removed and the product is obtained through recrystallization with alcohol. CH3C6H4OH+(CH3)3COH [H3PO4]→BHT 3.Alternatively, BHT is prepared from 2,6-di-tert-butylphenol by hydroxymethylation or aminomethylation followed by hydrogenolysis.

  • Fire Hazard

    2,6-Di-tert-butyl-4-methylphenol is combustible.

  • Preparation products

    2-tert-Butyl-4-methylphenol

  • Raw materials

    Etanol-->Sodium hydroxide-->Phosphorous acid-->tert-Butanol-->ISOBUTYLENE-->2-Methyl-1-propanol-->p-Cresol-->Dehydrolyzing agent-->Column plate