What is bromobutane
Bromobutane, also known as 1-bromobutane, is an essential fine chemical product. It is a colorless transparent liquid, insoluble in water, slightly soluble in carbon tetrachloride, chloroform, and miscible in ethanol, ether, and acetone. It is mainly used as an alkylating agent, solvent, and rare element extraction agent, and can also be used as an alkylating agent in organic synthesis.
The preparation method of bromobutane
The existing synthesis techniques of bromobutane mainly include n-butanol and sodium bromide sulfuric acid method, n-butanol and hydrobromic acid sulfuric acid method, n-butanol and hydrobromic acid solid acid-catalyzed method, n-butanol and bromine vulcanization method, etc.
Butanol and sodium bromide sulfuric acid method
The method is intermittent production, the consumption of concentrated sulfuric acid as a catalyst is large, and a large amount of dilute sulfuric acid is produced as a by-product, which seriously pollutes the environment. The production cost of the product is high, the product content is low, the equipment is corroded seriously, and the utilization rate is low. Environmental protection treatment or raw material recycling is relatively complicated and the treatment cost is high.
Butanol and hydrobromic acid sulfuric acid method
Hydrobromic acid and n-butanol react in the presence of catalyst sulfuric acid to produce 1-bromobutane. Since hydrobromic acid is a by-product of mass production of aryl bromide flame retardants, the production cost is low. However, when sulfuric acid is used as a catalyst, a large amount of dilute sulfuric acid will be produced during the production process, and the post-treatment is relatively troublesome.
Catalytic method of n-butanol and hydrobromic acid solid acid
The solid acid catalysis method is susceptible to catalyst failure, resulting in unstable product yield, and the catalyst synthesis and regeneration process is very complicated.
n-butanol and bromine vulcanization method
1. Mix n-butanol and hydrobromic acid at a molar ratio of 1:5, heat it to a reflux state, and then add it dropwise evenly and adjust the gas outlet speed, so that the dripping amount of liquid corresponds to the amount of steaming out so that the kettle liquid remains stable. However, the reaction time of this method is long, requiring 6-12 hours, the consumption of hydrobromic acid is large, and the utilization rate is low.
2. Preheat a certain amount of hydrobromic acid solution in the reactor until steam is generated, mix it into the reactor at a molar ratio of n-butanol and hydrobromic acid at 1:1, and increase the reaction temperature. But the reaction time of this method is still longer, is intermittent production, and can’t continuous production.
3. Preparation of bromobutane using a microchannel reactor
48% hydrobromic acid and 99% n-butanol are continuously passed to the microchannel reactor using a plunger pump, the feed rate of metered n-butanol is 5g/min, and the feed rate of hydrobromic acid is 13.6g/min, that is, the mol ratio of n-butanol and hydrobromic acid is 1:1.2.
After feeding, adjust the temperature and pressure of the reactor, use the cooling and heating temperature control system to adjust the system temperature to 140°C, and use the pressure valve to adjust the pressure at the front end of the system to 1.5MPa, no bubbles appear in the reaction section, and the residence time is 260s.
The reaction was quenched by tap water in the last module of the reactor. After the amount of material feed, the reaction temperature and the reaction pressure are stabilized, wait for 3 residence times and then take a sample.
The sample was allowed to stand for stratification, and the separated oil phase was washed with saturated sodium carbonate solution to pH = 7, then washed with water, and dried with anhydrous magnesium sulfate in the laboratory to obtain 1-bromobutane with a purity of 95%, and a conversion rate of n-butanol of 94%.
Application of bromobutane
1. For the preparation of butyl-terminated allyl polyoxyethylene ether
Butyl-terminated allyl polyoxyethylene ether has improved oil solubility, high-temperature resistance, acid and alkali resistance, and antifoaming ability compared with allyl polyoxyethylene ether containing hydroxyl group because the hydroxyl group in the molecular chain is replaced by butyl, and has unique functions. Butyl-terminated allyl polyoxyethylene ether can be used in the high-speed spinning oil of chemical fiber; it can also be used as an additive in high-temperature-resistant lubricating oil or heat-conducting oil; it can also be used in strong alkaline detergent formulations. In addition, it is an excellent cell opener and silicone foam stabilizer in the polyurethane industry.
2. For industrial production of tetra butyl phosphonium bromide
Using butane bromide, magnesium strips, phosphorus trichloride, and tetrahydrofuran (solvent) as starting materials, tributylphosphine is first produced, and then tetrabutylphosphonium bromide is synthesized from tributylphosphine, butane bromide and acetonitrile (solvent).
3. Other applications
Butyl bromide can be used as rare element extraction solvent, intermediate and alkylating agent; raw material for producing plastic ultraviolet absorbers and plasticizers; used as raw material for medicine (such as synthesizing scopolamine butyl bromide); raw material for synthesizing dyes and spices, raw material for preparing functional pigments (such as pressure-sensitive pigments, heat-sensitive pigments, and two-color pigments for liquid crystal); as raw materials for semiconductors, etc.
In the end
In the preparation and synthesis of bromobutane, it is still necessary to develop a new process to prepare 1-bromobutane with high efficiency, high yield, high selectivity, low cost, low by-products, and no pollution. At the same time, due to the wide application and huge demand for 1-bromobutane, it is more urgent to develop new technologies. Jinbang has many years of experience in producing 1-bromobutane and can provide large quantities of high-purity 1-bromobutane in a short period of time. Now, customers in need are welcome to contact us for free samples and the lowest quotation.