
Water treatment agents refer to chemicals added in the water treatment process in order to remove most of the harmful substances in the water (such as corrosives, metal ions, dirt and microorganisms, etc.) to obtain civil or industrial water that meets the requirements. Water treatment agents are an important category of fine chemical products and have strong specificity. It is widely used in petroleum, chemical, metallurgy, transportation, light industry, textile and other industrial sectors. Water treatment agents include corrosion inhibitors, scale inhibitors, bactericides, flocculants, purifiers, cleaning agents, pre-filming agents, etc.
Hydrolyzed polymaleic anhydride is a new type of scale inhibitor, which is polymerized from maleic anhydride. Also known as polymaleic anhydride, brown-yellow or brown-red transparent liquid. Easily soluble in water, dilute alkali, acetone, acetonitrile, lower alcohols, esters and nitroalkanes. As a low-molecular-weight maleic anhydride homopolymer, it has excellent scale inhibition and dispersion properties, and its high temperature resistance is far better than similar products. The most important thing is that it does not cause environmental pollution.
In addition to polymaleic anhydride, organophosphorus scale inhibitors are also commonly used corrosion and scale inhibitors, which are mainly used in industrial circulating water systems such as power plants, steel plants, fertilizer plants, oilfield water injection systems, and so on.
Technical index of a certain organic phosphorus corrosion and scale inhibitor:
Item | Index |
Appearance | Yellow-brown transparent liquid |
Active component (calculated by EDTMPS)%≥ | 28.0 |
Organic phosphorus (calculated as PO4)%≥ | 10.0 |
Phosphorous acid (based on PO3)%≥ | 5.0 |
Phosphoric acid (calculated as PO4)%≤ | 1.0 |
PH value (1% aqueous solution) | 9.5-10.5 |
Density (20℃)g/cm≥ | 1.25 |
Chloride (calculated by CI)%≤ | 3.0 |
This article mainly shares the detection methods of maleic acid in polymaleic anhydride and phosphite and phosphate in organic phosphorus corrosion and scale inhibitors.
Instrument configuration
- Ion chromatograph: IC6600, equipped with conductivity detector
- Autosampler: AS2800
- Eluent generator: EG6600, OH system
- Chromatography pump: P6600
- Chromatographic conditions

multi-function ion chromatograph
Chromatographic conditions
Column | IonPac AS11-HC4x250mm | ||
Eluent | KOH gradient elution | ||
Flow rate | 1.0mL/min | ||
Column temperature | 30℃ | Pond temperature | 35℃ |
Current | 120mA | Injection volume | 25μl |
Test chromatogram

