25/11/2024
Definition and Basic Information
Polyferric Sulfate (PFS) is an inorganic polymer coagulant. It is a kind of high - efficiency water - treatment agent that is widely used in water purification and wastewater treatment processes.
Production Method
It is usually produced by the reaction of ferrous sulfate () with an oxidizing agent such as hydrogen peroxide () or sodium chlorate () in an acidic environment. The reaction process involves the oxidation of ferrous ions () to ferric ions () and then the polymerization of the ferric ions to form the polymeric structure. For example, the reaction with hydrogen peroxide can be represented as:
And then further polymerization occurs to form the final polyferric sulfate product.
Properties
Coagulation and Flocculation:
PFS has excellent coagulation and flocculation abilities. It can neutralize the negative charges on the surface of suspended particles in water, causing them to aggregate and form larger flocs. These flocs can then be easily separated from the water through sedimentation or filtration processes. The mechanism involves the hydrolysis of the iron(III) ions in water to form various hydroxo - iron(III) complexes, which can adsorb and bridge the suspended particles.
pH Range:
It is effective over a relatively wide pH range, usually from 4 to 11. This wide applicability makes it suitable for different water quality conditions. In comparison with other coagulants, such as aluminum - based coagulants, PFS can maintain good performance even at higher pH values.
Stability:
Polyferric sulfate is relatively stable. It can be stored for a certain period without significant degradation. However, it should be stored in a dry and cool place to avoid the influence of moisture and high temperature, which may cause hydrolysis and affect its performance.
Applications
Drinking Water Treatment:
In the purification of drinking water, PFS is used to remove turbidity, color, and suspended solids. It can effectively reduce the content of harmful substances such as bacteria, viruses, and heavy metals by coagulating and precipitating them. The use of PFS can improve the quality of drinking water and meet the relevant standards for safe drinking water.
Wastewater Treatment:
For industrial wastewater and municipal wastewater treatment, PFS plays a crucial role. It can treat various types of wastewater, including textile wastewater, papermaking wastewater, and dyeing wastewater. For example, in textile wastewater treatment, it can remove dyes and other organic pollutants, and in papermaking wastewater treatment, it can reduce the suspended solids and chemical oxygen demand (COD).
（AbbreviationofPolyferricSulfate)
