Borax, also called coarse borax, is a soft and light colorless crystalline substance. Borax has many familiar uses, such as disinfectant, preservative, water softener, eye washing water, soap additive, ceramic glaze and glass raw materials, etc. Borax also plays an important role in industrial production.
Introduction:
Borax, also known as crude borax, is a sodium tetraborate containing 1 water molecules in chemical composition. Its crystals are plate-like or columnar, and the crystals gather together to form clusters, granular, porous clods, etc., and the color is white with gray borax-undisturbed < P > or yellow, blue and green with light tones, which has a glass luster.
Physical and chemical properties
Colorless translucent crystal or white crystalline powder. Odorless and salty. Specific gravity is 1.73. All crystal water is lost at 38℃. Soluble in water and glycerol, slightly soluble in alcohol. The aqueous solution is weakly alkaline. Borax can be slowly weathered in air. When melted, it becomes a colorless glassy substance. Borax has bactericidal effect, and oral administration is harmful to people. CAS: 133-96-4 Molecular formula: Na2B4O7·1H2O Molecular weight: 381.37 Boiling point: 1575℃ Melting point: about 88℃ Chinese name: borax sodium tetraborate (decahydrate) Lunatone sand yellow moon sand borax (medicinal). Industrial borax powder
decahydrate sodium tetraborate Lunatone sand sodium tetraborate English name: borax sodium borate sodium tetraborate, decahydrate sodium borate, decahydrate antipyronin borascu borax
uses
mainly used in glass and enamel industry. In glass, the ultraviolet transmittance can be enhanced, and the transparency and heat resistance of glass can be improved. In enamel products, it can make the enamel not easy to fall off and make it shiny. It is also widely used in special optical glass, borax
glass fiber, welding agent for nonferrous metals, adhesive for jewelry, printing and dyeing, washing (silk and woolen goods, etc.), gold refining, cosmetics, pesticides, fertilizers, borax soap, preservatives, antifreeze and medical disinfectants. Borax is the basic raw material for preparing boron-containing compounds, and almost all borides can be prepared by borax. They are widely used in metallurgy, steel, machinery, military industry, cutting tools, paper making, electron tubes, chemicals and textiles. In human medicine, borax is used for the disinfection and antisepsis of skin mucosa, the treatment of skeletal fluorosis, tinea pedis, pulpitis, fungal vaginitis, cervical erosion, bedsore, acne, eczema of external auditory canal, herpes virus dermatosis, epilepsy, and in recent years, it is also used for the treatment of tumors. In animal medicine, borax is used in the treatment of chicken laryngotracheitis, goat infectious pustulosis, mycoplasma hyopneumoniae and chronic mucinous endometritis of cattle, and it has also attracted much attention as a feed additive.
preparation method and technological process
borax
1. Pressurized alkaline hydrolysis: the pretreated boron magnesium ore powder is mixed with sodium hydroxide solution, heated and pressurized to decompose to obtain sodium metaborate solution, and then carbonized to obtain borax. 2MoG B2O3+2NaOH+H2O → 2nabo2+2mg (OH) 24Nabo2+CO2 → Na2B4o7+Na2CO32, carbon-alkali method: mix the pretreated boron-magnesium ore powder with sodium carbonate solution, heat it, introduce carbon dioxide to boost the pressure, and then react to obtain borax. 2 (2mo.b2o3)+Na2CO3+2co2+xh2o → Na2B4o7+4mo.3co2.xh2o3, soda alkali hydrolysis (well salt brine): after well salt brine is treated, borax paste is obtained, which is mixed with soda ash to obtain borax. Cab4o7+Na2CO3 → Na2B4 O7+CaCO3 4h3bo3+Na2CO3 → Na2B4 O7+6H2O+CO2 4. Alkaline hydrolysis of soda ash (ulexite): ulexite after pretreatment is decomposed with soda ash and baking soda, followed by precipitation and crystallization with causticized starch to obtain borax. 2 (nao.2cao.5b2o3.16h2o)+Na2CO3+nahco3 → 5na2b4o7+4co3+CO2+34h2o
The packaging of this paragraph is edited
It is packed in sacks lined with two layers of kraft paper or plastic bags. The net weight of each bag is 4 kg, 5 kg or 8 kg. Precautions for storage and transportation: it should be transported in boxcars, cabins or cars with sheds, and should not be mixed with damp materials or other colored materials. The means of transport must be dry and clean. Store in a dry and clean warehouse, and avoid rain or moisture.
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alias Lunatone borax ore refined crystal. The main producing areas are Qinghai, Tibet and Shaanxi. Method After the ore is dug out, it is dissolved in boiling water, and impurities are filtered out. After the filtrate is cooled, crystals are separated out, and then it is taken out and dried. Sexual taste is sweet, salty and cool. Enter the lung and stomach meridians. Function indications: clearing away heat and toxic materials for external use, reducing swelling and preventing corrosion; Clearing lung and resolving phlegm by oral administration. Used for acute tonsillitis, pharyngolaryngitis, sore throat, aphtha, stomatitis, gingivitis, otitis media, swelling and pain of eyes, and borax ecchymosis-medicinal < P >. It is a common drug for diseases of ENT! Oral administration is used for phlegm-heat cough, but it is rarely used in modern times. Usage and dosage: Apply appropriate amount externally, and grind powder with other drugs to apply to the affected area. Or externally washed, or prepared into eye drops for external use. Note that it is generally not taken orally. (1.5-3.g each time. ) Chinese medicine Bingpeng Powder (Authentic Surgery) Borneolum Syntheticum, Borax, Natrii Sulfate and Cinnabar. → Used to treat sores on the mouth and tongue and sore throat. Extracts from the National Collection of Chinese Herbal Medicines and the Textual Research of Chinese Materia Medica come from 1. Materia Medica Yanyi: Pengsha, which is heavily brown in the south, is mild in taste and quick in effect; Westerners, its color is white, its taste is burnt, and its work is slow. 2. "Compendium": Borax, born in the southwest. There are two kinds of yellow and white, the west is as white as alum, and the south is as yellow as peach gum, all of which are refined, such as sal. Western people soften things to remove dirt, kill hardware, work with saltpeter, and get along with arsenic. Borax, commonly known as sodium borate, is a white or colorless crystalline powder. Because of its high toxicity, borax is banned as a food additive in many countries around the world. Borax is very harmful to human health. Continuous intake will accumulate in the body and hinder the action of enzymes in the digestive tract. Its acute poisoning symptoms are vomiting, diarrhea, erythema, circulatory system disorder, shock and coma. If the human body ingests too much boron, it will cause cumulative poisoning of multiple organs. The toxic dose of borax is 1-3g for adults, 15g for adults and 2-3g for infants.
editing this modern research
The main component
is sodium tetraborate (Na2B4 O7 1H2O).
Pharmacological action
1. Bacteriostasis It has been reported that borax is a weak base, which has a weak bacteriostatic effect as boric acid. The culture medium contains 1% borax by plate method, which is harmful to Escherichia coli, Pseudomonas aeruginosa and Bacillus anthracis. It is proved by paper method that borax can also inhibit diphtheria Bacillus, Brucella bovis, pneumococcus, meningococcus and hemolytic streptococcus, etc. 2. The experiment of anticonvulsant and antiepileptic effect shows that borax has anticonvulsant effect in mice, and this effect can be gradually enhanced with the increase of administration times. The maximum anticonvulsant effect occurs about one week after administration. Injection can accelerate its anticonvulsant effect. The intraperitoneal injection of 26 mg/kg can resist electric convulsion, and its antagonistic rate is 1%. With other antiepileptic drugs, borax can quickly control grand mal and status epilepticus. 3. Other functions of borax also have the function of anticorrosion and protection of skin and mucosa. This product can be used to wash ulcers, abscesses, especially mucosal inflammation, such as conjunctivitis and epilepsy. Oral use for urethral sterilization, especially when urine is acidic, can make it alkaline.
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Borax; Sodium tetraborate English name Relative molecular weight or atomic weight 381.37 density 1.69 ~ 1.72 Borax < P > Toxic LD5(mg/kg) rats are easily soluble in water after oral administration of 566. The purpose is to extract boron and the main mineral raw materials of boron compounds. In metallurgical industry, borax is used for calcination, welding and metal testing, and it is also a good flux. In addition, it is also widely used in glass, ceramics, medicine, fertilizer, textile and other industries. Borax is one of the most widely distributed borate minerals, and it is the product of chemical deposition in salt lakes, which is more common in dry boron-containing salt lakes. Other hardness is 2 ~ 2.5. It is easy to lose crystal water in the air and become white powder. When burned, it expands and then melts into transparent glass-like balls. Borax is sodium tetraborate, containing 99.% ~ 15.% Na2B4O7.1H2O. Properties This product is colorless and translucent crystal or white crystalline powder; Odorless; Weathering; Alkaline reaction of aqueous solution. This product is soluble in boiling water or glycerol, soluble in water and insoluble in ethanol. Identify the identification reaction between sodium salt and borate in aqueous solution of this product. Check the clarity of the solution Take .5g of this product, add 1ml of water to dissolve it, and the solution should be clarified; If it is turbid, it shall not be thicker than the turbidity standard solution No.2 (Appendix ⅸ b). Take .25g of this product for chloride, and check it according to law (Appendix VIII A). Compared with the control solution made of standard borax < P > sodium chloride solution, it shall not be more concentrated (5.ml%). Take .5g of this product for sulfate, and check it according to law (Appendix VIII B). Compared with the control solution made of 2.ml of standard potassium sulfate solution, it shall not be more concentrated (.4%). Carbonate and bicarbonate take .25g of this product, add 5ml of water to dissolve it, and then add hydrochloric acid, without bubbling. Take .25g of calcium salt, dissolve it in 1ml of water, add acetic acid to make it acidic, add 1.ml of ammonium oxalate test solution, leave it for 1 minute, add 5ml of ethanol, shake it evenly, and after 15 minutes, if it becomes turbid, accurately weigh .125g of calcium carbonate dried to constant weight at 15 ~ 11℃ with standard calcium solution, put it in a 5ml volumetric flask, and add 5ml of water and hydrochloric acid. Before use, accurately measure 1ml, put it in a 1ml volumetric flask, add water to dilute it to scale, and shake it well. (Every 1ml is equivalent to 1μg of Ca)) 2.5ml of control solution made by the same method should not be thicker (.1%). Take 1.g of iron salt, dissolve it in 25ml of water, and check it according to law (Appendix VIII g). Compared with the control solution made of 3.ml of standard iron solution, it shall not be deeper (.3%). Take 1.g of this product for heavy metal, add 16ml of water to dissolve it, then add 1mol/L hydrochloric acid solution dropwise until it turns blue-purple when it meets Congo red test paper, then add a proper amount of water to make 25ml, and check it according to law (Appendix VIII H First Method). The content of heavy metal shall not exceed 1 parts per million. Content determination: Take about .4g of this product, weigh it accurately, add 25ml of water to dissolve it, add 1 drop of .5% methyl orange solution, titrate it with hydrochloric acid titration solution (.1mol/L) until it is orange red, boil it for 2min, cool it, if the solution is yellow, continue to titrate until the solution is orange red, add neutral glycerol (take 8ml of glycerol, add 2ml of water and 1 drop of phenolphthalein indicator solution, and use hydrogen. Every 1ml of sodium hydroxide titration solution (.1mol/L) is equivalent to 9.534mg of Na2B4O7.1H2O. Category disinfection and antiseptic drugs. Storage, sealing and preservation. [Crystal Chemistry] Theoretical composition (WB%): Na2O16.26, B2O3 36.51, H2O 47.23. [Structure and morphology] Monoclinic system, a=1.184nm, b=1.63nm, c=1.232nm；; β=16? 35'； Z=4。 In the crystal structure, borate is composed of two [BO3OH] tetrahedrons and two [BO2OH] triangles at the corners of each other. They are connected with the column (‖c axis) formed by [Na(H2O)6] octahedral * * * edges through hydrogen-oxygen bonds. This structural feature makes borax cleavage. Rhombohedral crystals, C2h-2/m(L2PC). Crystal shape is short column or thick plate. Common simplex: parallel double faces A, B, C, oblique square columns M, W, Q, X. Aggregates are crystal clusters, granules, blocks, spring flowers, beans, shells and so on. [Physical properties] Colorless or white, sometimes with light gray, light yellow, light blue, light green, etc. Glass luster. Cleavage is complete and incomplete. Sexually brittle. Conchoidal fracture. The hardness is 2~2.5. The relative density is 1.69~1.72. Soluble in water. It tastes sweet and slightly salty. Under the polarizer: colorless. Biaxial crystal (-). 2V=4。 Ng=1.472，Nm=1.469，Np=1.447。 [Occurrence and combination] It occurs in the evaporated sediments of salt lakes and dry salt lakes in arid areas, and is associated with halite, trona, ulexite, anhydrous mirabilite, potassium mirabilite, glauberite, gypsum, calcite, sodium mirabilite, mirabilite carbonate and other rare sulfates. In dry air, borax is easy to lose water and become white powdery tripartite borax. [Identification] Short columnar crystal shape, low hardness, easy to dissolve in water, sweet and slightly salty. It is easy to dehydrate in the air, the color becomes turbid, and cracks and white powder-like shells are formed on the surface. When it burns, it expands and easily melts into a glassy sphere. [Industrial Application] It is the most important industrial boron mineral. Borax is the most important compound of boron. Boron is often listed as a rare element abroad. However, there are abundant borax minerals in China, so boron is not a rare element in China, but a high-yield element. Borax is also used as a solid lubricant in metal wire drawing and other aspects in industry. It is often used as an (inactive) flux to purify the metal surface and remove oxides on the metal surface in the welding and maintenance of refrigeration equipment such as refrigerators, freezers and air conditioners. Adding a certain proportion of sodium chloride, sodium fluoride, potassium chloride and other compounds into borax can be used as active soldering flux for copper pipes and steel pipes in refrigeration equipment. Welding between steel pipes
Editing this paragraph Clinical application
Treatment of epilepsy
Borax is taken orally. The number of attacks is sparse. Look at .3 each time.