N-Butanol

Characteristics and history of discovery

1-Butanol is a type of alcohol with four carbon atoms being contained per molecule. Its molecular formula is CH3CH2CH2CH2OH with three isomers, namely iso-butanol, sec-butanol and tert-butanol. It is colorless liquid with alcohol odor.
It has the boiling point of being 117.7 ℃, the density (20 ℃) being ​​0.8109g/cm3, the freezing point being-89.0 ℃, flash point being 36~38 ℃, self-ignition point being 689F and the refractive index being (n20D) 1.3993. At 20 ℃, its solubility in water is 7.7% (by weight) while the water solubility in 1-butanol was 20.1% (by weight). It is miscible with ethanol, ether and other kinds of organic solvents. It can be used as the solvents of a variety of paints and the raw material for producing the plasticizers, dibutyl phthalate. It can also be used for the manufacture of butyl acrylate, butyl acetate, and ethylene glycol butyl ether and also used as the extract of intermediates of organic synthesis and biochemical drugs and can also used in the manufacture of surfactants. Its steam can form explosive mixtures with air with the explosion limit being 3.7%~10.2% (volume fraction).
1-butanol was first discovered by C-A. Wurtz (French) from the fusel oil obtained from the fermentation process of alcohol in 1852. In 1913, the British Strange-Graham Companies have used corn as raw material for production of acetone through the fermentation process with butanol being the main byproduct. Later, due to the increasing demand for butanol, the fermentation production factory began to mainly synthesize n-butanol with acetone and ethanol being the major byproduct. During the Second World War, the German chemical company (Ruhr) began to apply propylene carboxyl method for the production of 1-butanol. With the rise of the oil industry in 1950s, the 1-butanol synthesis method had gotten rapid development with the propylene carboxyl method having the fastest speed.

Preparation of water saturated 1-butanol solution

Add 21 mL of water and 100 mL of 1-butanol to separating funnel of 150 mL, shake for 3 min, stand for layering; and then remove the lower layer with the upper layer being water-saturated 1-butanol solution. (The density of water: 1 g/ml; 1-butanol density: 0.808~0.811 g/ml).

Content Analysis

For the determination of 1-butanol and volatile impurities according to the general gas chromatography (GT-10), use the following conditions:
Column steel column, length: 1.8m; inner diameter: 6.4mm, the packing material should be 10% polyethylene glycol 400M (PEG 400M) with the carrier being 60/80 mesh diatomaceous soil carrier.
Carrier gas: Helium with a flow rate of 45ml/min. Detector: Flame ionization type.
Injector temperature 150 ℃, column temperature 90 0 ℃ detector 150 ℃.
The above information is edited by the Chemicalbook of Dai Xiongfeng.

Toxicity

ADI value is not specified (FAO/WHO, 1994).
GRAS (FEMA).
LD50: 790 mg/kg (rat, oral).

Uses

1-Butanol is the most important in industries and the most extensively studied. 1-Butanol is a colorless liquid with a strong, mildly alcoholic odor. It is used in chemical derivatives and as a solvent for paints, waxes, brake fluid, and cleaners.
Butanol is the allowable food flavors documented in the "food additives health standards" of China. It is mainly used for the preparation of food flavors of bananas, butter, cheese and whiskey. For the candy, the usage amount should be 34mg/kg; for baked foods, it should be 32mg/kg; for soft drinks, it should be 12mg/kg; for cold drinks, it should be 7.0mg/kg; for the cream, it should be 4.0mg/kg; for alcohol, it should be 1.0mg/kg.
It is mainly used for the manufacture of the n-butyl plasticizers of phthalic acid, aliphatic dicarboxylic acid and phosphoric acid that are widely applied to various kinds of plastic and rubber products. It can also be used as the raw material of producing butyraldehyde, butyric acid, butyl-amine and butyl lactate in the field of organic synthesis. It can also be used as the extraction agent of oil, drugs (such as antibiotics, hormones and vitamins) and spices as well as the alkyd paint additives. It can be used as the solvent of organic dyes and printing ink and de-waxing agent.

Production method

There are several methods for their preparation.
Fermentation
In the past, the production of butanol has also used potatoes, grain or sugar as raw material and through their hydrolysis fermentation. The resulting product from the fermentation broth contains a butanol content of 54.8%~58.5%, acetone content of 30.9%~33.7%, and the ethanol content of 7.8%-14.2%. With the development of petrochemical industry, fermentation method has been gradually phased out. The reaction equation is as follows: (C6H10O5) n [n (H2O)] → [strain] n-C6H12O6 [fermentation] → CH3COCH3 + C4H9OH + C2H5OH
The resulted fermentation broth was further fractionated to obtain acetone, ethanol and n-butanol separately.
Acetaldehyde method
Take acetaldehyde as raw material, add dilute alkali solution to give 2-hydroxybutyraldehyde at temperature below 20 ℃ with the reaction being stopped upon reaching 50%. Use alkali to neutralize the acid and recycle the unreacted acetaldehyde and extract the 2-hydroxybutyraldehyde. Then use acidic catalyst such as sulfuric acid and acetic acid for dehydration to obtain crotonaldehyde at 105~137 ℃, then use copper complex catalyst for hydrogenation at 160~240 ℃ to obtain the crude butyraldehyde and 1-butanol with distillation to obtain the products. CH3CH = CHCHO + H2 [catalyst] CH3CH2CH2CHO + CH3CH2CH2CH2OH
Its synthesis method including the following several ways:
Fermentation and Propylene carbonyl synthesis
Put propylene, carbon monoxide and hydrogen to the catalytic bed for reaction with catalyst being zeolite for absorbing cobalt salt or fatty acid cobalt with the reaction temperature being 130~160 ℃ and the reaction pressure being 20~25MPa. The reaction can generate n-butyraldehyde and iso-butyraldehyde with separation via distillation and further catalytic hydrogenation of the n-butyraldehyde to obtain the 1-butanol. CH3CH2CH2CHO + H2 → CH3CH2CH2CH2OH
You can alternatively use low pressure method with first-step method of propylene, carbon monoxide and water for synthesizing the butanol with the reaction temperature being 100~104 ℃ and pressure being 1.5MPa. It applies the mixture of iron pentacarbonyl, n-butyl pyrrolidine and water. However, the one-way conversion of the propylene is low with only 8% to 10%. Reaction equation: CH3CH = CH2 + 3CO + 2H2O → n-C4H9OH + 2CO2

Description

n-Butyl alcohol is a colourless flammable liquid with strong alcoholic odour. n-Butyl alcohol is a highly refractive liquid and burns with a strongly luminous flame. It is incompatible with strong acids, strong oxidising agents, aluminium, acid chlorides, acid anhydrides, copper, and copper alloys. n-Butyl alcohol has an extensive use in a large number of industries. For instance, it is used as solvent in industries associated with the manufacturing of paints, varnishes, synthetic resins, gums, pharmaceuticals, vegetable oils, dyes, and alkaloids. n-Butyl alcohol finds its use in the manufacture of artificial leather, rubber, plastic cements, shellac, raincoats, perfumes, and photographic films.

Chemical Properties

n-Butyl alcohol is a colorless flammable liquid with a strong alcoholic odor. n-Butyl alcohol is a highly refractive liquid and burns with a strongly luminous flame. It is incompatible with strong acids, strong oxidizing agents, aluminium, acid chlorides, acid anhydrides, copper, and copper alloys. n-Butyl alcohol has extensive use in a large number of industries. For instance, it is used as a solvent in industries associated with the manufacturing of paints, varnishes, synthetic resins, gums, pharmaceuticals, vegetable oils, dyes, and alkaloids. n-Butyl alcohol is used in the manufacture of artificial leather, rubber, and plastic cements, shellac, raincoats, perfumes, and photographic films. It is a solvent, chemical intermediate and an additive in unleaded gasoline.

Chemical Properties

1-Butanol is a colorless, volatile liquid with a rancid sweet odor. The air odor threshold of 1-butanol was reported to be 0.83 ppm ; others have identified the minimum concentration with identifiable odor as 11 and 15 ppm.

Physical properties

Clear, colorless liquid with a rancid sweet odor similar to fusel oil. Experimentally determined detection and recognition odor threshold concentrations were 900 μg/m³ (300 ppb_v) and 3.0 mg/m³ (1.0 ppm_v), respectively (Hellman and Small, 1974). Odor threshold concentration in water is 500 ppb (Buttery et al., 1988). The least detectable odor threshold in concentration water at 60 °C was 0.2 mg/L (Alexander et al., 1982). Cometto-Mu?iz et al. (2000) reported nasal pungency threshold concentrations ranging from approximately 900 to 4,000 ppm.

Occurrence

1-Butanol is a natural product found in Vitis rotundifolia, Cichorium endivia, peppermint oil from Brazil, Achillea ageratum, tea, apple aroma, American cranberry, black currants, guava fruit, papaya, cooked asparagus, tomato, Swiss cheese, Parmesan cheese, heated butter, cognac, Armagnac, rum and cider.

Uses

As solvent for fats, waxes, resins, shellac, varnish, gums etc.; manufacture of lacquers, rayon, detergents, other butyl Compounds; in microscopy for preparing paraffin imbedding materials.

Uses

1-Butanol is used in the production of butylacetate, butyl glycol ether, and plasticizerssuch as dibutyl phthalate; as a solvent in thecoating industry; as a solvent for extractionsof oils, drugs, and cosmetic nail products;and as an ingredient for perfumes and flavor.
1-Butanol occurs in fusel oil and as aby-product of the fermentation of alcoholicbeverages such as beer or wine. It is presentin beef fat, chicken broth, and nonfilteredcigarette smoke (Sherman 1979).

Production Methods

The principal commercial source of 1-butanol is n-butyraldehyde obtained from the oxo reaction of propylene, followed by hydrogenation in the presence of a catalyst . 1-Butanol has also been produced from ethanol via successive dehydrogenation to acetaldehyde, followed by an aldol process. The earliest commercial route to 1-butanol, which is still used extensively in many Third World countries, employs fermentation of molasses or corn products with Clostridium acetobutylicum .

Definition

ChEBI: 1-Butanol is a primary alcohol that is butane in which a hydrogen of one of the methyl groups is substituted by a hydroxy group. It it produced in small amounts in humans by the gut microbes. It has a role as a protic solvent, a human metabolite and a mouse metabolite. It is a primary alcohol, a short-chain primary fatty alcohol and an alkyl alcohol.

Aroma threshold values

Detection: 500 ppb to 509 ppm

General Description

Colorless liquid. Used in organic chemical synthesis, plasticizers, detergents, etc.

Air & Water Reactions

Highly flammable. Soluble in water.

Reactivity Profile

1-Butanol attacks plastics. [Handling Chemicals Safely 1980. p. 236]. Mixtures with concentrated sulfuric acid and strong hydrogen peroxide can cause explosions. May form explosive butyl hypochlorite by reacting with hypochlorous acid. May form butyl explosive butyl hypochlorite with chlorine.

Hazard

Toxic on prolonged inhalation, irritant to eyes. Toxic when absorbed by skin. Flammable, moderate fire risk. Eye and upper respiratory tract irritant.

Health Hazard

Anesthesia, nausea, headache, dizziness, irritation of respiratory passages. Mildly irritating to the skin and eyes.

Health Hazard

The toxicity of 1-butanol is lower than thatof its carbon analog. Target organs are theskin, eyes, and respiratory system. Inhalationcauses irritation of the eyes, nose, and throat.It was found to cause severe injury to rabbits’eyes and to penetrate the cornea uponinstillation into the eyes. Chronic exposureof humans to high concentrations may causephotophobia, blurred vision, and lacrimation.
A concentration of 8000 ppm was maternallytoxic to rats, causing reduced weightgain and feed intake. Teratogenicity wasobserved at this concentration with a slightincrease in skeletal malformations (Nelsonet al. 1989).
In a single acute oral dose, the LD50 value(rats) is 790 mg/kg; in a dermal dose theLD50 value (rabbits) is 4200 mg/kg.
n-Butanol is oxidized in vivo enzymaticallyas well as nonenzymatically and iseliminated rapidly from the body in the urineand in expired air. It inhibits the metabolismof ethanol caused by the enzyme alcoholdehydrogenase.
Based on the available data, the useof n-butanol as an ingredient is consideredsafe under the present practices andconcentrations in cosmetic nail products(Cosmetic, Toiletry and Fragrance Association1987a).

Health Hazard

Exposures to n-butyl alcohol by inhalation, ingestion, and/or skin absorption are harm ful. n-Butyl alcohol is an irritant, with a narcotic effect and a CNS depressant. Butyl alcohols have been reported to cause poisoning with symptoms that include, but are not limited to, irritation to the eyes, nose, throat, and the respiratory system. Prolonged exposure results in symptoms of headache, vertigo, drowsiness, corneal infl amma tion, blurred vision, photophobia, and cracked skin. It is advised that workers com ing in contact with n-butyl alcohol should use protective clothing and barrier creams. Occupational workers with pre-existing skin disorders or eye problems, or impaired liver, kidney or respiratory function may be more susceptible to the effects of the substance.

Fire Hazard

HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water.

Safety Profile

A poison by intravenous route. Moderately toxic by skin Review: Group 3 IMEMDT 7,56,87; Animal Inadequate Evidence IMEMDT 39,67,86* contact, ingestion, subcutaneous, and intraperitoneal routes. Human systemic Reported in EPA TSCA Inventory. Community fight-To-Ihow List. OSHA PEL: TWA 10 pprn Classifiable as a Carcinogen DFG MAK: 2 ppm (11 mg/m3) DOT CLASSIFICATION: 3; Label: Flammable Liquid ingestion, inhalation, skin contact, and intraperitoneal routes. Experimental reproductive effects. A skin and eye irritant. Questionable carcinogen. A flammable fight fire, use foam, CO2, dry chemical. Incompatible with oxidzing materials. When heated to decomposition it emits acrid and irritating fumes. See also ESTERS. effects by inhalation: conjunctiva irritation, unspecified respiratory system effects, and nasal effects. Experimental reproductive Though animal experiments have shown the butyl alcohols to possess toxic properties, they have produced few cases of poisoning in industry, probably because of their low reported to have resulted in irritation of the eyes, with corneal inflammation, slight headache and H2ziness, slight irritation of the nose and throat, and dermatitis about fingers. Keratitis has also been reported. Mutation data reported.

Synthesis

n-Butyl alcohol is obtained by fermentation of glycerol, mannite, starches, and sugars in general, using Bacillus butylicus sometimes synergized by the presence of Clostridium acetobutryricum; synthetically, from acetylene.

Potential Exposure

Butyl alcohols are used as solvents for paints, lacquers, varnishes, natural and synthetic resins, gums, vegetable oils, dyes, camphor, and alkaloids. They are also used as an intermediate in the manufacture of pharmaceuticals and chemicals; in the manufacture of artificial leather, safety glass; rubber and plastic cements, shellac, raincoats, photographic films, perfumes; and in plastic fabrication.

First aid

If this chemical gets into the eyes, remove anycontact lenses at once and irrigate immediately for at least15 min, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts theskin, remove contaminated clothing and wash immediatelywith soap and water. Seek medical attention immediately. Ifthis chemical has been inhaled, remove from exposure,begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR ifheart action has stopped. Transfer promptly to a medicalfacility. When this chemical has been swallowed, get medical attention. Give large quantities of water and inducevomiting. Do not make an unconscious person vomit.

Source

1-Butanol naturally occurs in white mulberries and papaya fruit (Duke, 1992). Identified as one of 140 volatile constituents in used soybean oils collected from a processing plant that fried various beef, chicken, and veal products (Takeoka et al., 1996).

Environmental Fate

2Biological. 1-Butanol degraded rapidly, presumably by microbes, in New Mexico soils releasing carbon dioxide (Fairbanks et al., 1985). Bridié et al. (1979) reported BOD and COD values of 1.71 and 2.46 g/g using filtered effluent from a biological sanitary waste treatment plant. These values were determined using a standard dilution method at 20 °C for a period of 5 d. Heukelekian and Rand (1955) reported a similar 5-d BOD value of 1.66 g/g which is 64.0% of the ThOD value of 2.59 g/g. Using the BOD technique to measure biodegradation, the mean 5-d BOD value (mM BOD/mM 1-butanol) and ThOD were 3.64 and 60.7%, respectively (Vaishnav et al., 1987). In activated sludge inoculum, following a 20-d adaptation period, 98.8% COD removal was achieved. The average rate of biodegradation was 84.0 mg COD/g?h (Pitter, 1976).
Photolytic. An aqueous solution containing chlorine and irradiated with UV light (λ = 350 nm) converted 1-butanol into numerous chlorinated compounds which were not identified (Oliver and Carey, 1977).
Reported rate constants for the reaction of 1-butanol and OH radicals in the atmosphere: 6.8 x 10-10 cm³/molecule?sec at 292 K (Campbell et al., 1976), 8.31 x 10^-12 cm³/molecule?sec (Wallington and Kurylo, 1987). Reported rate constants for the reaction of 1-butanol and OH radicals in the atmosphere: 8.3 x 10^-12 cm³/molecule?sec at 298 K (Atkinson, 1990); with OH radicals in aqueous solution: 2.2 x 10^-9 L/molecule?sec (OH concentration 10-17 M) (Anbar and Neta, 1967). Based on an atmospheric OH concentration of 1.0 x 106 molecule/cm³, the reported half-life of 1-butanol is 0.96 d (Grosjean, 1997).
Chemical/Physical. Complete combustion in air yields carbon dioxide and water vapor. Burns with a strongly luminous flame (Windholz et al., 1983).
1-Butanol will not hydrolyze because it has no hydrolyzable functional group (Kollig, 1993).
At an influent concentration of 1,000 mg/L, treatment with GAC resulted in an effluent concentration of 466 mg/L. The adsorbability of the carbon used was 107 mg/g carbon (Guisti et al., 1974).

storage

Store n-butyl alcohol in a cool, dry, well-ventilated location, away from smoking areas. Fire hazard may be acute. Outside or detached storage is preferred. Separate from incompatibles. Containers should be bonded and grounded for transfer to avoid static sparks

Shipping

UN1120 Butanols, Hazard Class: 3; Labels: 3— Flammable liquid. UN1212 Isobutanol or Isobutyl alcohol, Hazard Class: 3; Labels: 3—Flammable liquid

Purification Methods

Dry it with MgSO4, CaO, K2CO3, or solid NaOH, followed by refluxing with, and distillation from, small amounts of calcium, magnesium activated with iodine, or aluminium amalgam. It can also be dried with molecular sieves, or by refluxing with n-butyl phthalate or succinate. (For method, see Ethanol.) n-Butanol can also be dried by efficient fractional distillation, water passing over in the first fraction as a binary azeotrope (contains about 37% water). An ultraviolet-transparent distillate has been obtained by drying with magnesium and distilling from sulfanilic acid. To remove bases, aldehydes and ketones, the alcohol is washed with dilute H2SO4, then NaHSO4 solution; esters are removed by boiling for 1.5hours with 10% NaOH. It has also been purified by adding 2g NaBH4 to 1.5L butanol, gently bubbling with argon and refluxing for 1 day at 50o. Then adding 2g of freshly cut sodium (washed with butanol) and refluxed for 1day. Distil and collect the middle fraction [Jou & Freeman J Phys Chem 81 909 1977]. [Beilstein 1 IV 1506.]

Toxicity evaluation

The primary effects observed following oral and inhalation exposure in rats and mice to n-butyl alcohol include neurological and neurodevelopmental effects. n-Butyl alcohol has been evaluated in a large number of experimental animal and in vitro studies examining possible mechanisms for alcoholinduced neurotoxicity. One proposed mechanism is that alcohols, in general, produce neurological changes by disrupting the lipid bilayer. A few experimental animal studies have shown that n-butyl alcohol, like other alcohols, can disrupt membrane integrity. Other in vitro and experimental animal studies have demonstrated that n-butyl alcohol interacts with protein-receptors and modulates their effects such that it potentiates inhibitory g-aminobutyric acid (GABA) and glycine receptors and inhibits excitatory neuronal receptors such a glutamate. This modulatory action of n-butyl alcohol is supportive of the observed neurobehavioral changes (e.g., central nervous system (CNS) depressant profile) associated with n-butyl alcohol exposure in humans.
In addition, experimental animal studies have shown that n-butyl alcohol inhibits fetal rat brain astroglial cell proliferation by disrupting the phospholipase D (PLD) signaling pathway. Inhibition of astroglial cell proliferation, which has been postulated as a mode of action for ethanol-induced microencephaly and mental retardation observed in cases of fetal alcohol syndrome. These mechanisms can also be relevant to the observed dilation in the brain that has been noted in animals gestationally exposed to n-butyl alcohol.

Incompatibilities

Butyl alcohols may form explosive mixture with air. In all cases they are Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides. Attacks some plastics, rubber and coatings. n-Butanol is incompatible with strong acids; halogens, caustics, alkali metals; aliphatic amines; isocyanates. sec-Butanol forms an explosive peroxide in air. Ignites with chromium trioxide. Incompatible with strong oxidizers; strong acids; aliphatic amines; isocyanates, organic peroxides. tert-Butanol is incompatible with strong acids (including mineral acid), including mineral acids; strong oxidizers or caustics, aliphatic amines; isocyanates, alkali metals (i.e., lithium, sodium, potassium, rubidium, cesium, francium). isoButanol is incompatible with strong acids; strong oxidizers; caustics, aliphatic amines; isocyanates, alkali metals and alkali earth. May react with aluminum at high temperatur

Waste Disposal

Incineration, or bury absorbed waste in an approved land fill.