Alias of uses of tetrafluoroboric acid
Hydrofluoroboric acid; tetrafluoroboric acid
The uses and physical and chemical properties of tetrafluoroboric acid
Colorless transparent liquid. strong acid. It cannot exist in pure form and can only exist in aqueous solution. Industrial products are generally 42% to 48% aqueous solutions. The relative density of 42% aqueous solution is 1.32; the relative density of 48% aqueous solution is 1.37. Fluoboric acid is stable in concentrated solutions and decomposes when heated to 130°C. Miscible with water or alcohol. It slowly decomposes in aqueous solution to generate hydroxyfluoroboric acid (HBF3OH). The stability gradually decreased when in contact with the glass surface. The hydrolysis degree of the 0.047mol/L fluoroboric acid solution increased from 20.6% to 72.6% after being stored in a glass container for 32 days. It is highly corrosive but does not corrode glass at room temperature. It can react with metal elements, metal fluorides, oxides, hydroxides or carbonates to form corresponding fluoroborates. Toxic!
Quality standards for the use of tetrafluoroboric acid
Reference standards
Uses and uses of tetrafluoroboric acid
Used as a cleaning and corrosive agent for oxides and silicate films on metal surfaces, and cleaning before electroplating of aluminum and alloys. The 2.5% solution is used for electrolytic polishing of pure aluminum and as a rewash solution for removing flux and electroplated parts from metal substrates. Used as catalyst, preservative, chemical reagent for alkylation and polymerization, and raw material for preparing various fluoroborates.
How to prepare tetrafluoroboric acid
Hydrofluoric acid method: According to the theoretical amounts of hydrofluoric acid and boric acid, slowly add boric acid to hydrofluoric acid under stirring, control the reaction temperature below 40°C, stop mechanical stirring after heating is completed, and heat at room temperature Leave it for more than 2 hours, and then filter and purify it to obtain the finished fluoboric acid product. The reaction formula is as follows:
4HF+H3B03→HBF30H+HF+2H20
HBF30H chloropyridine+HF→HBF4+H20
Safety of use of tetrafluoroboric acid
Toxicity: Poisonous.
Health hazards: Harmful to the body if inhaled, taken orally or absorbed through the skin. It has a strong irritating effect on eyes, skin, mucous membranes and respiratory tract. After inhalation, death may occur due to spasm, edema, inflammation of the larynx and bronchus, chemical pneumonia, and pulmonary edema. Symptoms of poisoning include burning sensation, coughing, wheezing, laryngitis, shortness of breath, headache, nausea and vomiting.
First aid measures: In case of inhalation, quickly leave the scene and go to fresh air. Keep your airway open. If breathing is difficult, give oxygen. If breathing stops, perform artificial respiration immediately and seek medical attention. When swallowing, rinse mouth with water, give milk or egg white, and seek medical attention.
Protective measures: Wear a self-priming filter gas mask (full face mask) or air respirator when you may be exposed to its smoke. Wear rubber acid and alkali resistant clothing. Wear rubber acid and alkali resistant gloves. Smoking, eating and drinking are prohibited at the work site. The maximum allowable concentration in the environment is 25 mg/m3.
Storage and transportation: Tetrahydrofuran is a secondary inorganic acid corrosive substance.
