Phosphino Carboxylic Acid


Phosphino carboxylic acid (PCA) associates characteristics of phosphonates as well as polyacrylates. The function is to provide a special equilibrium of limit inhibition and also dispersancy. The PCA has good tolerance to chlorine. And it is also compatible with a lot of microbiological control agents.

The PCA has excellent dispersion performance for the scale of calcium carbonate as well as calcium phosphate in circulating cool water system. The reason is via the introduction of a phosphonic group right into a carboxylic group. In addition, PCA has also good scale inhibition for barium sulfate, strontium sulfate as well as silica scale.

One more thing to note, phosphino carboxylic acid (PCA) can not be affected by chlorine or other oxidizing biocides in standard.

Phosphino Carboxylic Acid


Mechanism of Action:

Phosphino carboxylic acid inhibits scale buildup on surfaces through at least three mechanisms. (More details, click here.)

  1. Solubility enhancement or threshold effect, which reduces precipitation of low solubility inorganic salts.
  2. Crystal modification, which deforms the growing organic salt crystals to give small, irregular, readily fractured crystals that do not adhere well to surfaces.
  3. Dispersing activity, which prevents precipitated crystals or other inorganic particles from agglomerating and depositing on surfaces. Low molecular weight polymers are widely used to inhibit scaling in industrial water treatment.


AppearanceColorless or light yellow liquid
Solid content, %50 Min.
Total phosphor (as PO43-), %0.5 Min.
Density (20℃), g/cm31.20~1.30
pH (1% water solution)3.0~5.0


Phosphino carboxylic acid has advantages in a wide range of water quality, chemical stability, strong chlorine tolerance, etc. Engineers use it as scale and corrosion inhibitor in circulating cool water system. And also found in the oilfield refill water system.

ChemicalsApplication AreaApplication UseFeatures and Benefits
Phosphonocarboxylic Acid (POCA)Cooling WaterCalcium carbonate and calcium phosphate scale control.Multifunctional, phosphonate and polymer performance on the same molecule.
Sulphonated Phosphino Polycarboxylic Acid Polymer (PCA-S)Cooling WaterStabilized phosphate and zinc based cooling water programs.Control calcium phosphate and zinc deposits.
Phosphinocarboxylic Acid Polymer (PCA)BoilersSludge dispersantFDA approved, can be used in applications where steam may contact food.
Pulp & PaperDe-inking dispersantOutperforms polyacrylates. Excellent performance under pulp and paper conditions.
Paper machine depositEffective against barium sulphate and calcium oxalate.


When used alone, the dosage of 5-20 mg/L is preferred. It can also be used together with organophosphines, copolymer, a zinc salt or BTA.

Packing and storage:

200L plastic drum, IBC (1000L), customers’ requirements.

200L plastic drum 1000L IBC

Storage for ten months in a shady room and dry place.


71050-62-9, 23636-66-0, CTK1A2745, DTXSID00559205, Phosphoranecarboxylicacid (8CI,9CI), ZINC113998343