Sodium hexametaphosphate（SHMP chemical) of commerce is typically a mixture of polymeric metaphosphates, of which the hexamer is one. It is more correctly termed sodium polymetaphosphate, which is prepared by melting monosodium orthophosphate and cooling it rapidly then. SHMP can hydrolyze into sodium trimetaphosphate and sodium orthophosphate in aqueous solution, especially under acidic conditions.
Appearance: Colorless and transparent glass flake or white granular crystals.
Solubility: Soluble in water, Insoluble in organic solvents, strong hygroscopicity, soluble complexes can be formed with metal ions such as, calcium and magnesium.
Toxicity: Accident consumption of sodium hexametaphosphate can cause severe poisoning and even death. The most common symptoms of poisoning include shock, arrhythmia, and slow heartbeat. Once poisoned, you should go to the hospital for treatment as soon as possible.
Environmental impact: It is usually slightly harmful to water bodies. Don’t expose undiluted or large amounts of SHMP chemical to ground water, water channels or sewage systems. Don’t discharge materials into the surrounding environment without government permission.
|Item||Industrial grade||Food grade|
|Total phosphate, as P2O5 % ≥||68.0||68.0|
|Inactive phosphate, as P2O5 % ≤||7.5||7.5|
|Iron, as Fe % ≤||0.03||0.02|
|Ph value (1% solution) % ≤||5.8-7.0||5.8-6.5|
|Water insoluble % ≤||0.04||0.05|
|Heavy metals, as Pb % ≤||—||0.001|
|Arsenic, as As % ≤||—||0.0003|
|Fluoride as F % ≤||—||0.003|
1.Application in detergents and water treatment. It can prevent the iron and manganese dissolved in the water from redening and blackening due to oxidation. And prevent the precipitation of calcium and magnesium ions to form scale and reduce the heat transfer efficiency at the same time.
2.Used in food.
3.Application in mineral processing and oil field industry. Sodium hexametaphosphate is a commonly used inhibitor in flotation, which is mainly used to inhibit quartz and silicate minerals, as well as calcite, limestone and other carbonate minerals. In the oil field industry, as a drilling mud additive, SHMP chemical can avoid the precipitation of multivalent metal ions, improve the salt resistance of mud and reduce mud water loss. In addition, dissolving a certain amount of sodium hexametaphosphate and injecting it into the water pipe can form a thin film on the pipe wall to prevent corrosion of the pipe.
4.Application in metallurgy and meta anticorrosion. Adding some additives to sodium hexametaphosphate to repair the steel-making converter at a certain temperature and pressure can greatly extend the life of the converter. The integration of SHMP and divalent metal ions in solution can form a positively charged polyelectrolyte, which forms a dense, continuous films when it is adsorbed on the metal surface. The film can completely cover the corrosion micro-battery, reduce or prevent the corrosion current from passing to play a role of corrosion protection.
5.The role in color film processing. Sodium hexametaphosphate is an excellent soft water agent. It must be added in the configuration of color developer in order to reduce the hardness of water, prevent the formation of calcareous texture, ensure clear and bright color. Meanwhile, it have no effect on the oxidation and reduction of the developer.
6.Applications in the fiber industry. It can suppress the formation of metal soap in the refining process, make the colloid in the raw cotton easy to remove and improve the refining efficiency. In the bleaching process, it can prevent the decomposition of hydrogen peroxide, reduce the loss of bleach and improve the bleaching efficiency. In the dyeing, it can prevent the color of the dyed substance from changing, maintain the original color of the dye, prevent the occurrence of dyeing stains, poor feel, white cloth yellowing and fiber strength reduction.
7.Used in paper-making industry. The mixture of SHMP chemical and sulfonated benzaldehyde can be used as a dispersant for steel paper coatings to disperse lead carbonate pigments.