disodium disulphite

disodium disulphite - Names and Identifiers

Name	Sodium metabisulfite
Synonyms	fertisilo Sodium Metabi SODIUM DISULFITE Sodium disulphite Sodium pyrosulfite Sodiummetabisufite Sodium pyrosulphite disodium disulphite Metabisulfite Sodium disodiumpyrosulphite Sodium metabisulfite disodiummetabisulfite metabisulfitedesodium Sodium metabisulphite SodiumMetabisulphiteAcs SodiumMetabisulphiteExtraPure disodium oxidosulfanesulfonate oxide
CAS	7681-57-4
EINECS	231-673-0
InChI	InChI=1/2Na.H2O5S2/c;;1-6(2)7(3,4)5/h;;(H,1,2)(H,3,4,5)/q2*+1;/p-2
InChIKey	HRZFUMHJMZEROT-UHFFFAOYSA-L

disodium disulphite - Physico-chemical Properties

Molecular Formula	2Na.O5S2
Molar Mass	190.11
Density	1.48
Melting Point	>300 °C (lit.)
Boling Point	150℃
Water Solubility	540 g/L (20 ºC)
Solubility	540 g/L (20°C)
Appearance	White to yellowish crystals
Specific Gravity	1.48
Color	White to slightly yellow
Odor	Sulphorous
Exposure Limit	ACGIH: TWA 5 mg/m3NIOSH: TWA 5 mg/m3
Merck	14,8638
PH	3.5-5 (50g/l, H2O, 20℃)
Storage Condition	Store at +5°C to +30°C.
Stability	Stable. Incompatible with strong oxidizing agents, strong acids. Contact with strong acids releases a poisonous gas. May be moisture and air sensitive.
Sensitive	Air & Moisture Sensitive
MDL	MFCD00167602
Physical and Chemical Properties	White or yellowish crystalline powder. The relative density is 1.4 The solubility is soluble in water, and the aqueous solution is acidic. Soluble in glycerol, ethanol-soluble.
Use	Used as bleaching agent, mordant, reducing agent, rubber coagulant, also used in organic synthesis, pharmaceutical and perfume

disodium disulphite - Risk and Safety

Risk Codes	R22 - Harmful if swallowed R31 - Contact with acids liberates toxic gas R41 - Risk of serious damage to eyes R36/37/38 - Irritating to eyes, respiratory system and skin. R52 - Harmful to aquatic organisms
Safety Description	S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S39 - Wear eye / face protection. S46 - If swallowed, seek medical advice immediately and show this container or label. S36 - Wear suitable protective clothing. S16 - Keep away from sources of ignition.
UN IDs	3260
WGK Germany	1
RTECS	UX8225000
TSCA	Yes
HS Code	2832 10 00
Packing Group	III
Toxicity	LD50 orally in Rabbit: 1540 mg/kg LD50 dermal Rat > 2000 mg/kg

disodium disulphite - Upstream Downstream Industry

Raw Materials	Sodium carbonate Sulfur(α)
Downstream Products	Sodium hydrosulfite Ether 3-Methyl-1-phenyl-2-pyrazolin-5-one Benzenesulfinic acid,sodium salt 1,3,3-trimethyl-2-methyleneindoline phenyl hydrazine 1,2-Naphthoxydiazo-4-sulfonic acid Sodium hydroxyethyl sulfonate Permethrin

disodium disulphite - Reference

Reference

1. Huang Hannian, Jiang Jianhui, Wang Rui, Zhao Ling Ling, cattle mu. Dosimetric study of focal region size in high intensity ultrasound [J]. Journal of Anhui Health Vocational and Technical College, 2016,15(06):112-113 115.
2. [IF = 4.952] Yulong Wei et al."Characterization of blueberry (Vaccinium corymbosum L.) catechol oxidases III binding mechanism in response to selected substrates and inhibitors." Lwt Food Sci Technol. 2022 Mar;158:113142

disodium disulphite - Nature

Open Data Verified Data

white or yellowish crystalline powder with a relative density of 1.4. Unstable, heated to 150 ° C above the decomposition of sulfur dioxide, soluble in water and glycerol, insoluble in ethanol. Can absorb oxygen in the air and oxidation to sodium sulfate. Strong reducing agent, and alkali to generate sodium sulfite, and acid release sulfur dioxide.

Last Update：2024-01-02 23:10:35

disodium disulphite - Preparation Method

Open Data Verified Data

A certain amount of soda ash was added to the sodium bisulfite solution to form a suspension of sodium sulfite. Sulfur dioxide is introduced to generate sodium metabisulfite crystallization, which is obtained by centrifugal separation and drying. Alternatively, the sodium carbonate solution is used to absorb sulfur dioxide gas to generate sodium bisulfite solution. When the end point of the reaction, it is precipitated from the saturated solution of sodium bisulfite, dehydrated by centrifugation, and dried.

Last Update：2022-01-01 08:59:15

disodium disulphite - Standard

Authoritative Data Verified Data

This product contains Na2S205 not less than 95.0%.

Last Update：2024-01-02 23:10:35

disodium disulphite - Trait

Authoritative Data Verified Data

This product is colorless to off-white crystalline or crystalline powder.
This product is soluble in water, very slightly soluble in ethanol.

Last Update：2022-01-01 11:27:06

disodium disulphite - Introduction

It smells of sulfur dioxide. It is gradually oxidized to sodium sulfate in the air. Decompose above 150 ℃. Soluble in water (64g/100ml) and glycerin, slightly soluble in ethanol, the aqueous solution is acidic, solid, this product is sodium metasulfite (Na2S2O5). When dissolved in water, NaHSO3 is obtained. Median lethal dose (rat, vein) 115mg/kg. It is irritating to the skin and mucous membranes.

Last Update：2022-10-16 17:28:33

disodium disulphite - Use

Open Data Verified Data

photographic developer. It can also be used as food bleaching agent, preservative, color fixative, coagulant, antioxidant and preservative, printing and dyeing mordant, rubber coagulant, and also the raw material for the production of chloroform, phenyl propyl sulfone and benzaldehyde.

Last Update：2022-01-01 08:59:15

disodium disulphite - Differential diagnosis

Authoritative Data Verified Data

take the iodine test solution, Dropwise add an appropriate amount of the aqueous solution (1-20) of this product, and the color of iodine will disappear; The obtained solution shows the identification reaction of sulfate (General rule 0301).
This product shows the flame reaction of sodium salt (General rule 0301).

Last Update：2022-01-01 11:27:07

disodium disulphite - Safety

Open Data Verified Data

The skin, mucous membrane has obvious stimulation, can cause conjunctiva, bronchitis symptoms. Staff should be protected. Store in a cool, dry, well-ventilated warehouse. Keep away from fire and heat source. Keep the container sealed. Should be stored separately from the oxidant, acids, edible chemicals, avoid mixing storage.

Last Update：2022-01-01 08:59:16

disodium disulphite - Exam

Authoritative Data Verified Data

acidity

take l.Og of this product, dissolve it with 20ml of water, and measure it according to law (General rule 0631). The pH value should be 3.5~5.0.

clarity and color of solution

take l.Og of this product, dissolve it with 10ml of water, and check it according to law (General rule 0901 and general rule 0902). The solution should be clear and colorless.

chloride

take 0. 10g of this product and check it according to law (General rule 0801). Compared with the control solution made of 5.0 ml of standard sodium chloride solution, it should not be more concentrated (0.05%).

thiosulfate

take 2.2g of this product, slowly add 10ml of dilute hydrochloric acid, dissolve it in a water bath and heat it for 10 minutes, let it cool, displace it in the colorimetric tube, add water to 20ml, if it is turbid, with sodium thiosulfate titration solution (0.1mol/L )0.lml should not be more concentrated (0.05%) than the control solution prepared by the same method.

Iron Salt

take this product l. After dissolving 5ml of water and 2ml of hydrochloric acid, the solution was dried on a water bath, and the residue was added with 15ml of water and 2ml of hydrochloric acid. After dissolving, the appropriate amount of bromine test solution was added to make the solution yellowish, and the excess bromine was removed by heating, cool, add water to 25ml, check according to law (General 0807 ) , and standard iron solution 2.0 ml of the control solution should not be deeper (0.002%).

Heavy metals

take this product l. After dissolving in 10ml of water, add 5ml of hydrochloric acid, dry on a water bath, add 15ml of water to the residue, slowly boil for 2 minutes, let it cool, add appropriate amount of bromine test solution to clarify, heat to remove excess bromine, cold, add 1 drop of phenolphthalein indicator solution and an appropriate amount of ammonia test solution to make the solution pink, add 2ml of acetate buffer solution (pH3.5) and an appropriate amount of water to make 25ml, and check according to law (General rule 0821 method 1), heavy metals should not be more than 20 parts per million.

arsenic salt

take 2.0g of this product, dissolve it with 4ml of water, slowly add 3ml of nitric acid Dropwise, and dry it on a water bath, add 5ml of hydrochloric acid and 23ml of water to the residue, dissolve it, inspection according to law (General Principles 0822 first law), shall comply with the provisions (0.0001%).

Last Update：2022-01-01 11:27:08

disodium disulphite - Content determination

Authoritative Data Verified Data

take about 0.15g of this product, weigh it accurately, put it in an iodine flask, add 50ml of Iodine titration solution (0.05mOl/L) accurately, close the plug, shake and dissolve it, then add lml of hydrochloric acid, with sodium thiosulfate titration solution (0.1 mol/L) titration, when the end point is near, add 2ml of starch indicator solution, continue titration until the blue color disappears; And correct the titration result with blank test. Each 1 ml of Iodine titration solution (0.05mol/L) is equivalent to 4.752mg of Na2S205.

Last Update：2022-01-01 11:27:08

disodium disulphite - Category

Authoritative Data Verified Data

pharmaceutical excipients, antioxidants and bacteriostatic agents.

Last Update：2022-01-01 11:27:09

disodium disulphite - Storage

Authoritative Data Verified Data

shading, sealed storage, avoid high temperature.

Last Update：2022-01-01 11:27:09

disodium disulphite - Reference Information

. Take a sample of about 0.2g (weigh to 0.0002g), add to the iodine solution, plug and place for 5min. 5ml of 2mol of HCL was added and titrated with 0.1mol of sodium thiosulfate standard solution. Near the end point, 2ml of 0.5% starch indicator was added, and titration was continued until the blue color disappeared as the end point. Another 50ml of 0.1mol L iodine solution was used for blank test under the same conditions.

pH range of acid-base indicator discoloration	4.5 at 50g/l at 20°C
EPA chemical substance information	information provided by: ofmpeb.epa.gov (external link)
Introduction	sodium metabisulfite is a white or yellow crystalline powder or small crystals with strong SO2 odor and acidic aqueous solution, contact with strong acid will release SO2 and generate the corresponding salts, long placed in the air, the oxidation of Na2S2O6, so the product can not be stored for a long time.
Use	as a preservative, bleach, coagulant in food processing. Industrial sodium metabisulfite for printing and dyeing, organic synthesis, printing, leather, pharmaceutical and other sectors; Sodium metabisulfite in the chemical industry, the pharmaceutical industry for the production of sodium hydrosulfite, sulfamethazine metamizide, caprolactam and chloroform, purification of benzene and formaldehyde. The photographic industry is used as an ingredient of a fixing agent. The perfume industry is used for the production of vanillin. Used as preservatives in the brewing industry, rubber coagulant and cotton dechlorination agent after bleaching. Organic intermediates, dyes, leather used as reducing agent used in electroplating industry, oilfield wastewater treatment and used as mineral dressing agent. used as chromatographic analysis reagent, preservative and reducing agent, used in dye and pharmaceutical industry used as bleaching agent, mordant, reducing agent, rubber coagulant, also used in organic synthesis, The pharmaceutical industry is used to produce chloroform, phenylpropyl sulfone and benzaldehyde. The rubber industry is used as a coagulant. The printing and dyeing industry is used as a dechlorination agent after bleaching of cotton and a cooking aid for cotton. Leather industry for leather processing, can make the leather soft, plump, tough, waterproof, flexural, wear-resistant and other properties. The chemical industry is used to produce hydroxyvanillin, hydroxylamine hydrochloride, etc. The photosensitive industry is used as a developer and the like. sodium metabisulfite has stronger reducibility, similar to sodium sulfite. China's provisions can be used for preserved fruits, biscuits, sugar, ice sugar, sugar, candy, glucose, liquid glucose, bamboo shoots, mushrooms and canned mushrooms, the maximum use of 0.45g/kg. Candied fruit, bamboo shoots, mushrooms and canned mushrooms, grapes and blackcurrant juice concentrate residues (as SO2) less than 0.05/kg; Biscuits, sugar, the residual amount of fans and other varieties is less than 0.1g/kg; The residual amount of liquid glucose should not exceed 0.2g/kg. used in food industry as bleaching agent, preservative, coagulant, antioxidant, color fixative and preservative. It is used in printing and dyeing, organic synthesis, printing, leather making, pharmaceutical and other departments in the industry; It is used as preservative, bleach and coagulant in food processing. for analysis. Preservatives. Reducing agent. Antioxidant
Use range	According to China's regulations GB2760-86: as a preservative used in fruit wine, the maximum use of 0.25g/kg; as a bleaching agent for glucose, sugar, bamboo shoots, mushrooms, etc., not more than 0.45g/kg; Residues (SO2), bamboo shoots, mushrooms not more than 0.025g/kg, fruit wine, sugar should not exceed 0.05g/kg, other varieties should not exceed 0.1g/kg.
content analysis
toxicity	ADI 0~0.7mg/kg (based on SO2, including total ADI values of SO2 and sulfite; FAO/WHO, 1999). GRAS(FDA,§ 182.3766,2000). According to China's GB 2760-86: as a preservative for fruit wine, the maximum use of 0.25g/kg; As a bleaching agent for glucose, sugar, bamboo shoots, mushrooms, etc, not more than 0.45g/kg; Residues (in SO2), bamboo shoots, mushrooms shall not exceed 0.025g/kg, wine, sugar shall not exceed 0.05g/kg, other varieties should not exceed 0.1g/kg.
Use limit	GB 2760-1996(g/kg): candied fruit, biscuits, glucose, sugar, ice sugar, sugar, candy, liquid glucose, bamboo
production method	absorption method uses food-grade soda ash solution to absorb sulfur dioxide to generate sodium metabisulfite, which is refined, filtered and dried, food-grade sodium metabisulfite was prepared. Na2CO3 2SO2 H2O → 2NaHSO3 CO22Na2SO3 → Na2S2O5 H2O The crushed sulfur is sent to the combustion furnace, and the compressed air is about 2 times of the theoretical amount, and spontaneous combustion is carried out at 600~800 ℃. After cooling, dust removal and water washing, it is sent to a multi-stage reactor for reverse absorption with sodium carbonate solution; The temperature of the absorption liquid is controlled at about 45 ℃, and the crystal slurry flowing out of the multi-stage reaction is separated by centrifugation, drying below 160 °c is the finished product. O2 S[Na2CO3 → NaHSO3[-H2O] → Na2S2O5 absorption method sodium metabisulfite was prepared by absorbing sulfur dioxide with soda ash solution, separating and drying. Its S O2 → SO2Na2CO3 2SO2 H2O → 2NaHSO3 CO22NaHSO3 → Na2S2O5 H2O
category	toxic substances
toxicity grade	poisoning
Acute toxicity	oral-rat LD50 1131 mg/kg
stimulation data	Skin-rabbit 500 mg positive; eyes-rabbits 100 mg/24 h mild
flammability hazard characteristics	non-combustible; toxic oxides of sodium and sulfur
storage and transportation characteristics	warehouse low temperature, ventilation, dry
extinguishing agent	water, carbon dioxide, dry powder, sand
Occupational Standard	TWA 5 mg/m3
toxic substance data	information provided by: pubchem.ncbi.nlm.nih.gov (external link)