Name | BORON TRIFLUORIDE, N-PROPANOL REAGENT 15 |
Synonyms | BORON TRIFLUORIDE-PROPANOL BORON TRIFLUORIDE-PROPANOL COMPLEX BORON TRIFLUORIDE, N-PROPANOL REAGENT 15 |
CAS | 762-48-1 |
EINECS | 678-347-8 |
Molecular Formula | C3H7BF3O |
Molar Mass | 126.89 |
Density | 0.905g/mLat 25°C(lit.) |
Flash Point | 96°F |
Merck | 14,1349 |
Storage Condition | 2-8°C |
Refractive Index | n20/D 1.379(lit.) |
Physical and Chemical Properties | Physical properties: density 2.99g/L, melting point -126.8 ℃, boiling point -99.9 ℃, critical temperature:-12.25 ℃, saturated vapor pressure (-58 ℃):1013.25 kPa; Soluble in organic solvent, soluble in cold water, concentrated sulfuric acid and concentrated nitric acid, insoluble in benzene, dichlorobenzene, chloroform, carbon tetrachloride and carbon disulfide. Chemical properties: immediately hydrolyze when exposed to moisture in the air, and generate highly toxic fluoride smoke when decomposed; hydrolyze in hot water to generate fluoroboric acid and boric acid, which are decomposed in ethanol and easily form a stable adduct BF3 •(C2H5)2O with ether. It cannot burn, does not support combustion, and can quickly form complexes with water, alcohols, phenols, amines, phosphines, esters, ketones, etc. Wet BF3 can corrode many metals; dry BF3 generally does not react with elemental metals, but can form addition compounds or alkyl metal compounds with many substances. Common reactions are: 2BF3 SiO2 → 2BOF ↑ SiF4 ↑ 4BF3 3H2O → 3HBF4 H3BO3 Morphology and properties: highly toxic, colorless and suffocating gas, irritating, producing white irritating smoke in the air. |
Risk Codes | R14 - Reacts violently with water R26 - Very Toxic by inhalation R35 - Causes severe burns R10 - Flammable |
Safety Description | S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S28 - After contact with skin, wash immediately with plenty of soap-suds. 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.) |
UN IDs | UN 2920 8/PG 2 |
WGK Germany | 3 |
RTECS | ED2275000 |
FLUKA BRAND F CODES | 10-21 |
Hazard Class | 8 |
Packing Group | I |
Overview | Boron fluoride, also known as boron trifluoride, has been used in the synthesis of high-energy fuels for rockets. It is an inorganic compound that is suffocating and does not burn., Colorless gas with irritating odor. Hydrolyze immediately when exposed to moisture in the air. When decomposed, highly toxic fluoride smoke is generated. Because it is an electron-deficient compound and electron docking acceptor, it can be used as a catalyst for many organic synthesis reactions, such as esterification, alkylation, polymerization, isomerization, sulfonation, nitration, etc. It is to prepare boron halide and element. The main raw materials of boron, borane, sodium borohydride, etc. In petroleum products, boron fluoride can also be used as a raw material for the synthesis of organic borides as a catalyst for polymerization, alkylation and condensation reactions. Boron fluoride and compounds are used as curing agents in epoxy resins. It can be used as a raw material for preparing optical fiber preforms. As boron trifluoride has a pivotal position in the fields of petrochemical, pharmaceutical production and national defense chemical industry, developed countries such as the United States, Germany, Japan, etc. have professional large-scale boron trifluoride production plants. Among them, the bottled boron trifluoride produced by United Signal Company of the United States and BASF of Germany has a high international influence. The boron trifluoride produced by Japan's Iron and Steel Chemical Company is relatively small in scale despite its high purity. China's research on boron trifluoride started in the late 50s. at that time, in order to meet the needs of China's national defense chemical industry, Guangming chemical research institute (now renamed as: Guangming chemical research and design institute) carried out research on the synthesis, analysis and complexation of boron trifluoride for the production of high-energy fuel diborane (NaH BF3 ※ B2H6 NaF). The analysis and corrosivity of boron trifluoride were systematically explored, and the software package necessary for boron trifluoride design was obtained. Later, according to needs, the project was transferred to other units for production. my country currently uses borax as raw material to produce boron trifluoride ether and acetonitrile complexes. The technology used is basically Guangming Chemical Research and Design Institute in the 2060s Scientific research results. |
preparation method | common preparation methods can be divided into three categories: fluoroborate thermal decomposition method, concentrated sulfuric acid eutectic method and direct fluorination method. fluoroborate high temperature thermal decomposition method this method uses the nature of fluoroborate easy to decompose and release BF3 at high temperature. the reaction mechanism is as follows: NaBF4 → BF3 ↑ NaF KBF4 → BF3 ↑ KF for example, taking sodium fluoroborate as an example, the melting point of sodium borate is 384 ℃, and it starts to decompose slowly at 400 ℃, when the temperature reaches 700 ℃, rapid decomposition begins. The process of preparing BF3 is as follows: This method has the advantages of simple equipment and high product purity. However, the raw material fluoroborate is more expensive and the process is not continuous. This method is not suitable for mass production of BF3 gas. concentrated sulfuric acid co-calorimetry (1) fluorite boron anhydride method such as CaF2, B2O3 and fuming sulfuric acid reaction method to prepare BF3. The reaction principle is: CaF2 + H2SO4 → CaSO4 + 2HF ↑ 6HF + B2O3 → 2BF3 ↑ + 3H2O the process equipment is simple and easy to operate, but the process produces highly corrosive HF with low yield. (2) reaction method of borax and liquid hydrofluoric acid the reaction principle is as follows: Na2B4O7 10H2O + HF → Na2O4BF3 + H2O Na2O4BF3 + H2SO4 → NaHSO4 + BF3 ↑ the operation steps are: first put a beaker filled with 200 mL hydrofluoric acid in an ice bath, then slowly add 120 g of ground borax, and slowly introduce HF after adding, the yield can be further improved. After the reaction, the precipitate is filtered, dried and mixed with 50 mL of fuming sulfuric acid to slowly heat and react to obtain BF3. the process is simple and the raw material price is cheap, but the BF3 produced contains more SiF4 impurities, which is not easy to refine in the later stage, and the highest yield of the product is only about 78%. (3) heating the mixture of fluoroborate, boric anhydride and concentrated sulfuric acid to prepare BF3 the principle of this method is: NH4BF4 + B2O3 + H2SO4 → BF3 ↑ NH4HSO4 + H2O the process is simple, but more water is generated in the reaction process, even if excessive fuming sulfuric acid is added, it cannot be completely removed. The generated boron trifluoride hydrate BF3 • nH2O condenses on the surface of the equipment, which affects the improvement of the purity of BF3 products. However, this method has certain application value for the waste utilization of phosphate ore processed by acid method. (4) reaction method of boric acid and hydrogen fluoride BF3 is prepared by reacting H3BO3 or B2O3 with HF at normal temperature in the environment of fuming sulfuric acid. First, fuming sulfuric acid is added to the reaction kettle, then B2O3 or H3BO3 is added, SO3 is introduced, and HF is finally introduced. The mass composition is fuming sulfuric acid 3~5,H3BO3 0.4~1.5,SO3 2~4,HF 2~7. The system temperature is controlled at 50~100 ℃ when SO3 and HF are applied. The method has the advantages of low reaction temperature, high safety and less waste liquid. (5) BF3 is prepared by reaction of BF3 hydrate and fuming sulfuric acid this method requires high concentration range of BF3 in BF3 hydrate, and the mass fraction of BF3 in BF3 hydrate is 47% ~ 65.3 %, which is mainly used in the regeneration process of BF3. (6) fluorosilicic acid and boric acid method in this method, fluorosilicic acid (H2SiF6) is first reacted with boric acid or boric anhydride to prepare fluoroboric acid and silicoboric acid, which are concentrated and heated with fuming sulfuric acid to prepare BF3. The BF3 prepared by this method has high purity and the volume fraction of impurity SiF4 is only 0.06%. (7) boric acid fluorosulfonic acid method fluorosulfonic acid (HSO3F) and boric acid H3BO3 (or dehydrated forms of boric acid HBO2, H2B4O7 and B2O3) react to prepare BF3 gas. 3HSO3F + H3BO3 → BF3 +3H2SO4 (8) boric acid fluorite method BF3 was prepared by co-heating boric acid, fluorite powder and fuming sulfuric acid. Preparation principle: Use the dehydration effect of fuming sulfuric acid to dehydrate boric acid to obtain boric anhydride. Under the action of potassium dichromate, boron trioxide, fluorite powder and fuming sulfuric acid can be mixed and heated to obtain BF3. H3BO3 → B2O3 + 3H2O + Q 3H2SO4 + B2O3 +3CaF2 → 3CaSO4+3 H2O +2 BF3 ↑ the comprehensive reaction formula is: 3 H2SO4 +2 H3BO3 +3 CaF2 → 3 CaSO4 +2 BF3 ↑ 6H2O + Q the chemical reaction formula of this method is: 2B +3 F2 → 2 BF3 the process flow is as follows: the specific operation steps: after the F2 prepared by electrolysis is frozen and liquefied, the volatile impurities in the F2 are removed, and the purified F2 enters the reactor 4 through the pipeline, and contacts with the elemental boron preheated to above 150 ℃ to generate BF3 containing a small amount of impurities. The product gas passes through the dust collector 5 to remove the solid substances therein, then enters the rectification tower 6, and removes the air and other impurity gases therein through rectification to obtain high-purity BF3. The volatile components separated from the rectification tower 6 pass through the adsorption tower After adsorption treatment, enter the exhaust gas treatment system, and then discharge after the treatment reaches the standard. With this process, BF3 8kg with a volume fraction of 99.995% was successfully achieved. the reaction process of preparing BF3 by fluorination method effectively avoids the generation of water in the production process of fluorite borate. BF3 has high yield, less impurity generation and easy distillation and purification. At the same time, it overcomes the shortcomings of the high cost of raw materials and the continuous process of the fluoroborate high-temperature thermal decomposition method, and the application of this method can produce high-purity BF3 gas in large quantities. |
purification method | for different impurities, the purification process of BF3 gas is mainly divided into cold trap method, low temperature rectification method, selective adsorption method, chemical conversion method, method combination (adsorption and chemical conversion, adsorption and rectification combination), etc. 1. cold trap method cold trap method is the simplest purification gas method to achieve separation effect by using the different boiling points of various gases. light component gases such as N2, O2 and Ar in impurity gases can be removed by cold trap method. The method is as follows: The cold trap method is simple to operate and low in cost. However, only the gas purified by the cold trap method removes part of the impurity gas, and the obtained gas has low purity and cannot be used in the electronic gas industry. Therefore, it is necessary to further purify BF3 gas by other methods. 2, low temperature distillation method low temperature distillation method is to take advantage of the gas-liquid equilibrium state, the low boiling point component content in the gas phase is higher than the liquid phase of the characteristics, in the distillation column through many times of partial evaporation and partial condensation of the gas-liquid equilibrium process, to achieve the separation and purification of different components. SiF4 impurity gas can be removed by low-temperature distillation. The process flow chart is as follows: 1-rectification tower; 2-condenser; 3-reboiler 3. selective adsorption method selective adsorption method is to use the difference of adsorption capacity of adsorbent to each component in gas to achieve the purpose of separation and purification. The selective adsorption method can remove CO2, CF4, SO2 and other impurity gases. The commonly used adsorption methods are mainly physical adsorption, and the commonly used adsorbents include molecular sieve, activated carbon, and additive. In order to remove impurities most economically, effectively and safely, activated carbon adsorption method is widely used. the selective adsorption method is easy to operate, the equipment is safe, and the adsorbent can be recycled, but the selectivity of inorganic inorganic adsorbent is relatively poor, the performance is not stable, and it is difficult to carry out continuous industrial production. 4. Chemical transformation method Chemical transformation method is a method to remove impurities through chemical reaction. At present, HF impurities in electronic gas are mainly removed by distillation or water washing, but the above method is difficult to apply because BF3 is easily soluble in water. NaF adsorption conversion HF has an extremely important application in the purification process of fluorine-containing electronic gas [28]. NaF is a good adsorbent. HF is adsorbed because the two substances react chemically to form NaHF2 to remove HF. The chemical transformation method has a wide range of applications, relatively simple operation, and can be recycled. It has important applications in gas purification. 5, combined purification (1) combination of adsorption and chemical conversion in the gas feeding stage, CO2, CF4, SO2 and other impurity gases are removed through the adsorption tower. In order to reduce the pressure loss of the packed tower, the adsorbent filled by the packed tower is preferably spherical, ellipsoidal or multilateral column type packing. HF was then removed by means of a stainless steel tower fitted with NaF. The combination of chemical conversion and adsorption is simple to operate, and the purity of the obtained BF3 gas is improved, but the SiF4 impurity gas cannot be effectively removed. (2) Combination of Adsorption and Distillation The patent applied by Tianjin Taiyuan Industrial Gas Co., Ltd. discloses a method of combined purification of rectification and adsorption. The installation diagram is as follows: 1-Raw material inlet pipe; 2-reboiler; 3-packed tower; 4-condenser; 5-low boiling point impurity discharge pipe; 6-liquid product removal pipe; 7-product receiving tank; 8-cooling jacket; 9-heating jacket; 10-high boiling point impurities refer to the above figure, rectification is carried out in packed tower 3, and the high boiling point impurities content of BF3 vapor formed at the top of the tower is low. The vapor is condensed and refluxed in the condenser, and the low boiling point components are discharged from the low boiling point impurity discharge pipe. The purified liquid BF3 is stored in the product receiving tank. this process is reasonable and simple to prepare. by this method, stable and continuous operation can be achieved. The impurities in BF3 can be reduced to less than 1 μL/L, and the problem of environmental pollution is solved at the same time. It is an ideal BF3 preparation technology. (3) improved purification method-laboratory study of high abundance boron trifluoride electronic special gas from the above combined purification process, it can be seen that the combined operation process of adsorption and rectification has certain research significance and economic benefits for the purification of boron trifluoride. the BF3 obtained by this method has high purity and can be used in large-scale electronic industry. According to the basis of the above methods, our laboratory proposes an improved gas purification method for enriched BF3 gas with high abundance. the process flow chart is as follows: 1-mixed packing adsorber; 2-Na F adsorber; 3-cold trap; 4-liquid nitrogen storage tank; 5-distillation tower BF3 gas is fed to remove CO2, CF4, SO2 and other impurity gases through adsorber 1, temperature control in the range of − 50 ~ − 90 ℃ using low temperature adsorption is better. Then enter the adsorber 2 to remove HF impurity gas, the temperature is controlled at 20 ℃, the pressure is about 0.15 MPa, and the adsorption flow rate is about 0.2 L/min. At this time, the adsorption efficiency is the highest. Light component gases such as N2, O2 and Ar are removed through a cold trap, and finally impurity gases such as SiF4 are removed by low-temperature rectification. this method is reasonable, easy to operate, and can achieve stable operation, combined with physical adsorption, chemical conversion, cold trap and low temperature distillation methods, and different operation methods are adopted for different impurity gases, so that the impurity content in BF3 gas is further reduced, and finally high purity BF3 gas is obtained. table 1 comparison of several purification methods |