Kieselsure, Natriumsalz

VERY SOL IN COLD & HOT WATER; SOLUBLE IN DILUTE SODIUM HYDROXIDE; INSOLUBLE IN ALCOHOL, ACIDS /NONAHYDRATE/

SOL IN WATER; INSOL IN ALCOHOL

INSOL IN ACIDS, SALT SOLN

In commerce mole ratios of SiO2 to Na2O vary from 1.5 to 3.3. ... The higher the ratio (e.g., the less sodium) the lower the solubility and alkalinity.

VERY SLIGHTLY SOL OR ALMOST INSOL IN COLD WATER; LESS READILY SOL IN LARGE AMT OF WATER THAN IN SMALL AMT; ANHYD DISSOLVE WITH MORE DIFFICULTY THAN HYDRATE IN WATER

GLASS FORM SOL IN STEAM UNDER PRESSURE; PARTIALLY MISCIBLE WITH PRIMARY ALC & KETONES; MISCIBLE WITH SOME POLYHYDRIC ALC

BOILING POINT: 100 °C -6H20 /NONAHYDRATE/

102 °C @760 [mm Hg]

1089 °C

MELTING POINT: 48 °C IN WATER OF CRYSTALLIZATION; HEAT OF HYDRATION: -24.15 KCAL/MOLE; EFFLORESCENT; ORTHORHOMBIC BIPYRAMIDAL PLATELETS /NONAHYDRATE/

1089 °C

General term for a group of compounds with varying quantities of sodium oxide (Na2-O) and silica (Si2-O); Aqueous solutions are characterized by the weight ratio of silica to sodium oxide, usually 1.6 to 3.8; Solutions are strongly alkaline and corrosive; [Merck Index] A strong skin and eye irritant; Toxic by ingestion at high doses; [CAMEO] A medium strong base in solution; 25-50% Aqueous solution: Aerosol is a skin, eye, and respiratory tract irritant; [ICSC] Corrosive to rabbit skin (when tested at 53.5% molar ratio of 1.6 and 82% molar ratio of 2.4); Sodium metasilicate was not sensitizing in a local lymph node assay study of mice; Similar uses and adverse effects are expected from the hydrous and anhydrous forms (Sodium metasilicate pentahydrate, Sodium metasilicate nonahydrate, Sodium metasilicate, Sodium silicate, and Potassium silicate). The main hazard of soluble silicates is their alkalinity and potentially corrosive effects on metal and tissue. [Ullmann]

A corrosive substance that can cause injury to the skin, eyes, and respiratory tract; [ICSC] A strong skin, eye, and mucous membrane irritant; [CAMEO] Causes burns; A respiratory tract irritant; [IUCLID] In high-dose, 4-week feeding studies of dogs and rats, polydipsia and polyuria were observed; Dogs but not rats had renal lesions; Oral LD50 (rat) = 1280 mg/kg (10% solution); [HSDB] pH of 1% solution = 13; [IPCS-PIMs] No reports on reproductive effects; [REPROTOX] Corrosive to moistened rabbit skin; Not sensitizing in a local lymph node assay study of mice; Similar uses and adverse effects are expected from the hydrous and anhydrous forms (Sodium metasilicate pentahydrate, Sodium metasilicate nonahydrate, Sodium metasilicate, Sodium silicate, and Potassium silicate). One case of occupational contact urticaria reported from sodium silicate; [OECD SIDS: Soluble Silicates - 2004] A severe skin irritant; Human ingestion of 1 mL/kg causes changes in tubules (including acute renal failure and necrosis), hematuria, and nausea or vomiting; [RTECS] Causes burns; Inhalation may cause corrosive injuries to upper respiratory tract and lungs; [Alfa Aesar MSDS]

Chemical: Sodium metasilicate

Chemical: Sodium silicate

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Pesticides for which EPA had not issued Registration Standards prior to the effective date of FIFRA, as amended in 1988, were divided into three lists based upon their potential for human exposure and other factors, with List B containing pesticides of greater concern and List D pesticides of less concern. Sodium metasilicate is found on List D. Case No: 4081; Pesticide type: insecticide, fungicide, antimicrobial; Case Status: RED Approved 09/91; OPP has made a decision that some/all uses of the pesticide are eligible for reregistration, as reflected in a Reregistration Eligibility Decision (RED) document.; Active ingredient (AI): Sodium metasilicate; AI Status: OPP has completed a Reregistration Eligibility Decision (RED) document for the case/AI.

As a general rule, pesticide chemicals other than ..., sodium metasilicate (not to exceed 4% by weight in aqueous solution)... are not for the purposes of section 408(a) of the Act generally recognized as safe.

Residues of sodium metasilicate are exempted from the requirement of a tolerance when used as a surfacant, emulsifier, wetting agent, suspending agent, dispersing agent, or buffer in accordance with good agricultural practices as inert (or occasionally active) ingredients in pesticide formulations applied to growing crops or to raw agricultural commodities after harvest.

Residues of sodium silicate are exempted from the requirement of a tolerance when used as a surfactant, emulsifier, wetting agent, stabilizer, or inhibitor in accordance with good agricultural practices as inert (or occasionally active) ingredients in pesticide formulations applied to growing crops or to raw agricultural commodities after harvest.

SODIUM SILICATE contains a variable amount of water of hydration. Rate of dissolution depends on the degree of hydration, the amount of water that is used as solvent (less soluble in large amounts of water) and the temperature (higher temperature means quicker solution). Aqueous solutions react as bases. Reacts violently with fluorine [Lewis.]

Range of trace impurities in typical sodium silicate solutions (3.3 silicon dioxide:sodiun oxide) fluoride, 6.7-9.5 ppm; chloride, 130-1900 ppm; sulfate, < 160-1,700 ppm; nitrogen, 0.1-44 ppm; arsenic, < 1-< 1 ppm; mercury, < 0.26-2.5 ppb; lead, 0.17-0.60 ppm; cadmium, < 10-21 ppm; iron, 36-120 ppm; magnesium, 4-26 ppm; calcium, < 1-76 ppm; aluminum, 50-220 ppm; phosphorus, < 18-< 18 ppm; vanadium, < 0.3-0.8 ppm; chromium, < 0.3-1.0 ppm;; nickel, < 0.3-< 0.3 ppm; cobalt, < 0.3-< 0.3 ppm; zinc, < 0.6-2.8 ppm; copper, < 0.6-1.1 ppm; bismuth, < 25-< 25 ppm; strontium, < 0.2-1.5 ppm; barium, < 0.2-2.8 ppm; manganese, 0.1-1.8 ppm; tin, < 60-< 60 ppm; antimony, < 15-< 15 ppm; selenium< 20-< 20 ppm. /From table/

2023: 1,000,000,000 - <2,500,000,000 lb

2023: 100,000,000 - <250,000,000 lb

(1972) 2.52X10+11 G (INCL ORTHOSILICATE)

(1975) 1.91X10+11 G-INCL ORTHOSILICATE

(1979) NOT PRODUCED COMMERCIALLY IN USA

(1984) 1.50 billion lb

(ALL SODIUM SILICATES): 35% TO MAKE SILICA GEL AND CATALYSTS; 18% AS ADDITIVES TO DETERGENTS & SOAPS; 15% AS CORROSION-INHIBITING BINDERS FOR PIGMENTS; 10% AS COMPONENT OF BOXBOARD ADHESIVES; 6% AS WATER CLARIFYING AGENT, A BLEACH STABILIZER FOR PAPER & A DISPERSANT & SURFACE CONDITIONER FOR ORE TREATMENT; & 16% FOR MISC USES (1975)

End use pattern soaps & detergents, 35%; silica type catalysis & gels, 25%; pigments, 23% adhesives, 5%; miscellaneous, 12% (1985)

Bleaching agent

Dye

Binder

Surfactant (surface active agent)

FUSION OF SODIUM CARBONATE WITH SILICON DIOXIDE OR SILICA SAND

FUSING OF SILICA SAND WITH SODA ASH IN AN OPEN HEARTH FURNACE (FOR SODIUM SILICONATE, THE MOLE WEIGHT RATIO OF SILICA SAND TO SODA ASH EQUALS 0.67; FOR COMMERCIAL SODIUM SILICATES,THE MOLE WEIGHT RATIO VARIES FROM 0.5 TO 3.75)

Grades or purity: A wide variety of grades, which differ in concentration of sodium silicate in water, in specific gravity, and in viscosity.

... COMMONLY EMPLOYED AS A 40% SOLN WHICH IS STRONGLY ALKALINE.

... Commonly available sodium silicates in dry form are: Na2SiO3, Na6Si2O7, and Na2Si3O7, with variable amounts of water ... .

Information on 437 consumer products that contain Sodium silicate in the following categories is provided:

Information on 297 consumer products that contain Sodium metasilicate in the following categories is provided:

Information on 2 consumer products that contain Sodium metasilicate in the following categories is provided:

EPA Safer Chemical Functional Use Classes -> Processing Aids and Additives

Safer Chemical Classes -> Green circle - The chemical has been verified to be of low concern

EPA Safer Chemical Functional Use Classes -> Processing Aids and Additives

Safer Chemical Classes -> Green circle - The chemical has been verified to be of low concern

Cosmetics -> Anticorrosive; Buffering; Chelating

Plastics -> Polymer Type -> N.a.