Magnesium Oxide USP Grade Specifications:
MgO 40.30
Magnesium oxide CAS 1309-48-4

DEFINITION
Magnesium Oxide, after ignition, contains NLT 96.0% and NMT 100.5% of magnesium oxide (MgO).

IDENTIFICATION
A. Identification Tests-General, Magnesium: A solution in diluted hydrochloric acid meets the requirements.

ASSAY
To pass the test.
Acceptance criteria: 96.0% to 100.5% after ignition.

Free Alkali and Soluble Salts
To pass the test. Acceptance criteria: 96.0% to 100.5% after ignition.
Free Alkali and Soluble Salts:
Sample solution: Boil 2.0 g with 100 mL of water for 5 min in a covered beaker, and filter while hot. Allow to cool and dilute with water to 100 mL. Analysis 1: To 50 mL of the Sample solution add methyl red and titrate with 0.10 N sulfuric acid. Acceptance criteria 1: NMT 2.0 mL of the acid is consumed. Analysis 2: Evaporate 25 mL of the remaining Sample solution to dryness, and dry at 105C for 1 h. Acceptance criteria 2: NMT 10 mg of residue remains (NMT 2.0%).
Acid-Insoluble Substances:
Sample: 2 g Analysis: Mix the Sample with 75 mL of water, add hydrochloric acid in small portions with agitation until no more dissolves, and boil for 5 min. If an insoluble residue remains, filter, wash well with water until the last washing is free from chloride, and ignite. Acceptance criteria: The weight of the ignited residue is NMT 2 mg (NMT 0.1%). Limit of Calcium: to pass the test. Iron: to pass the test. --- NMT 0.05%
Loss on Ignition:
Sample: 500 to 1000 mg Analysis: Transfer the Sample to a tared platinum crucible and ignite in the temperature range of (800C to 900C) ± 25C to constant weight. Acceptance criteria: NMT 10.0% Bulk Density and Tapped Density of Powders, Bulk Density: Using the procedure specified in the chapter, determine the bulk density of Magnesium Oxide. Packaging and Storage: Preserve in tight containers.

Heavy Magnesium Oxide BP Ph Eur Grade Specifications
Ph Eur
MgO --- 40.30 CAS 1309-48-4
Action and use: Antacid; osmotic laxative.

DEFINITION
Content: 98.0 per cent to 100.5 per cent of MgO (ignited substance).

CHARACTERS
Appearance: Fine, white or almost white powder.
Solubility: Practically insoluble in water. It dissolves in dilute acids with at most slight effervescence.

IDENTIFICATION
A. 15 g has an apparent volume (2.9.15) before settling of not more than 60 ml.
B. Dissolve about 15 mg in 2 ml of dilute nitric acid R and neutralise with dilute sodium hydroxide solution R. The solution gives the reaction of magnesium.
C. Loss on ignition (see Tests).

TESTS
Solution S: Dissolve 5.0 g in a mixture of 30 ml of distilled water and 70 ml of acetic acid, boil for 2 min, cool and dilute to 100 ml with dilute acetic acid. Filter, if necessary, through a previously ignited and tared porcelain or silica filter crucible of suitable porosity to give a clear filtrate.
Appearance of solution: Solution S is not more intensely coloured than reference.
Soluble substances: Maximum 2.0 per cent.
To 2.00 g add 100 ml of water and boil for 5 min. Filter whilst hot through a sintered-glass filter (40) (2.1.2), allow to cool and dilute to 100 ml with water. Evaporate 50 ml of the filtrate to dryness and dry at 100-105C. The residue weighs a maximum of 20 mg.
Substances insoluble in acetic acid: Maximum 0.1 per cent.
Any residue obtained during the preparation of solution S, washed, dried, and ignited at 600 ±50C, weighs a maximum of 5 mg.
Chlorides: Maximum 0.1 per cent.
Sulphates: Maximum 1.0 per cent.
Arsenic: Maximum 4 ppm, determined on 5 ml of solution S.
Calcium: Maximum 1.5 per cent.
Iron: Maximum 0.07 per cent.
Heavy metals: Maximum 30 ppm.
Loss on ignition: Maximum 8.0 per cent, determined on 1.00 g at 900 ± 25C.

Specifications of Light Magnesium Oxide BP Ph Eur Grade
Light Magnesia
MgO -- 40.30 -- CAS 1309-48-4
Action and use: Antacid; osmotic laxative.

DEFINITION
Content: 98.0 per cent to 100.5 per cent of MgO (ignited substance).

CHARACTERS
Appearance: Fine, white or almost white, amorphous powder.
Solubility: Practically insoluble in water. It dissolves in dilute acids with at most slight effervescence.

IDENTIFICATION
A. 15 g has an apparent volume (2.9.15) before settling of at least 100 ml.
B. Dissolve about 15 mg in 2 ml of dilute nitric acid and neutralise with dilute sodium hydroxide solution. The solution gives the reaction of magnesium.
C. Loss on ignition (see Tests).

TESTS
Solution S: Dissolve 5.0 g in a mixture of 30 ml of distilled water and 70 ml of acetic acid, boil for 2 min, cool and dilute to 100 ml with dilute acetic acid. Filter, if necessary, through a previously ignited and tared porcelain or silica filter crucible of a suitable porosity to give a clear filtrate.
Appearance of solution: Solution S is not more intensely coloured than reference solution.
Soluble substances: Maximum 2.0 per cent.
Substances insoluble in acetic acid: Maximum 0.1 per cent.
Chlorides: Maximum 0.15 per cent.
Sulphates: Maximum 1.0 per cent.
Arsenic: Maximum 4 ppm, determined on 5 ml of solution S.
Calcium: Maximum 1.5 per cent.
Iron: Maximum 0.1 per cent.
Heavy metals: Maximum 30 ppm.
Loss on ignition: Maximum 8.0 per cent, determined on 1.00 g at 900 ± 25C.

Light Magnesium Oxide IP Grade Specifications
Light Magnesia
MgO ---- Mol.Wt.40.30
Category: Antacid, Osmotic Laxative.

Description: Very fine, light, white powder, odourless. 15g occupies a volume of about 150ml.
Solubility: Practically insoluble in water, insoluble in ethanol(95%).It dissolves in dilute acids with at most slight effervescence.

STANDARDS:
Light Magnesium Oxide contains not less than 98.0 per cent and not more than 100.5per cent of MgO, Calculated with reference to the substance ignited at 900C.

Identification:
Arsenic; Heavy metals; Sulphates; Calcium; Soluble substances; Substances insoluble in acetic acid ; Loss on ignition: Complies with the requirements stated under Heavy Magnesium Oxide using, where appropriate, solution A and residue R prepared as described therein.
Colour of Solution: Prepare Solution A and residue R as described in the test for colour of solution under Heavy Magnesium Carbonate. Solution A is not more than intensely Coloured than reference solution.
Iron: Solution complies with the limit test for iron, Appendix 3.13 (0.1%).
Chloride: 4.0ml of solution A complies with the limit test for chlorides, Appendix 3.10(0.125%)

Magnesium Oxide FCC Food Grade Specifications
MgO Formula wt 40.30
INS: 530 CAS: [1309-48-4]

DESCRIPTION
Magnesium Oxide occurs as a very bulky, white powder known as Light Magnesium Oxide or as a relatively dense, white powder known as Heavy Magnesium Oxide. Five grams of Light Magnesium Oxide occupies a volume of approximately 40 to 50 mL, while 5 g of Heavy Magnesium Oxide occupies a volume of approximately 10 to 20 mL. It is soluble in dilute acids, practically insoluble in water, and insoluble in alcohol.
Function: pH control; neutralizer; anticaking agent; freeflowing agent; firming agent.

REQUIREMENTS
Labeling: Indicate whether it is Light Magnesium Oxide or Heavy Magnesium Oxide.
Identification: A solution of sample in 2.7 N hydrochloric acid gives positive tests for Magnesium.
Assay: Not less than 96.0% and not more than 100.5% of MgO after ignition.
Acid-Insoluble Substances: Not more than 0.1%.
Alkalies (Free) and Soluble Salts: Passes test.
Arsenic: Not more than 3 mg/kg.
Calcium Oxide: Not more than 1.5%.
Lead: Not more than 4 mg/kg.
Loss on Ignition: Not more than 10.0%.

Specifications of Magnesium Oxide Analytical Reagent Grade
MgO
Formula Wt 40.30
CAS Number 1039-48-4

REQUIREMENTS
Assay: 95.0% MgO

MAXIMUM ALLOWABLE
Insoluble in dilute hydrochloric acid: 0.02%
Water-soluble substances: 0.4%
Loss on ignition: 2.0%
Ammonium hydroxide precipitate: 0.02%
Chloride (Cl): 0.01%
Nitrate (NO3): 0.005%
Sulfate and sulfite (as SO4): 0.02%
Barium (Ba): 0.005%
Calcium (Ca): 0.05%
Manganese (Mn): 5 ppm
Potassium (K): 0.005%
Sodium (Na): 0.5%
Strontium (Sr): 0.005%
Heavy metals (as Pb): 0.003%
Iron (Fe): 0.01%

We also manufacture Micro-Encapsulated Magnesium Oxide, having core of Magnesium Oxide and coating of vegetable oil or mono and diglycerides or as desired by the buyer. Such encapsulation makes the product slow release or extended release.