Can Polymeric Ferric Sulfate Be Used for Heavy Metal Wastewater Treatment?

Polyferric sulfate (PFS) can indeed be used to treat wastewater with excessive heavy metals, and has shown good removal effect in practice. The following is the main mechanism and influencing factors of polyferric sulfate treatment of heavy metal wastewater, and then follow the polyferric sulfate manufacturers to understand it.

The mechanism of action of polyferric sulfate:

Charge neutralization: The iron ions(Fe³ +)  in polyferric sulfate are able to charge neutralize heavy metal ions in water, reducing their stability in water and thereby facilitating the removal of heavy metal ions.

Adsorption bridge: PFS can form polymer polynuclear complexes, which have strong adsorption capacity, can adsorb heavy metal ions in water, form larger particles, and facilitate subsequent sedimentation or filtration removal.

Coprecipitation: Under the right pH conditions, polyferric sulfate can form insoluble precipitations with heavy metal ions, such as hydroxide or sulfide, thereby removing them from water. For example, heavy metal ions such as copper, zinc, and lead can form insoluble hydroxide precipitates with the hydrolysates of PFS.

Complexation: the polyvalent iron ions in PFS can form stable complexes with some heavy metal ions. This complexation not only changes the existence of heavy metals, but also reduces their solubility in water, which is convenient for subsequent removal.

Factors affecting the effect of polyferric sulfate:

pH value: pH value has a significant effect on the treatment of heavy metal wastewater by polyferric sulfate. The optimal pH range for removal of different heavy metals varies. In general, for most heavy metals, the optimal pH range is between 6.5 and 9. In this range, the hydrolysates of PFS and heavy metal ions are more likely to form insoluble precipitates.

Types and concentrations of heavy metals: Different types of heavy metal ions have different reactivity with PFS, and the concentration will also affect the removal efficiency. Generally speaking, PFS has a good removal effect on heavy metal ions such as copper, zinc, lead and cadmium. For extremely high concentrations of heavy metal wastewater, it may be necessary to combine other treatment techniques, such as ion exchange, reverse osmosis or advanced oxidation processes, to meet more stringent discharge standards.

Temperature: Temperature will affect the hydrolysis rate and complexation reaction rate of polyferric sulfate, which will affect the removal effect. In the suitable temperature range (generally 20°C to 40°C), the removal efficiency of heavy metal ions by PFS is higher.

Other ions co-existing in water: Certain ions (such as calcium, magnesium, phosphate, etc.) may compete with PFS or interfere with their binding to heavy metal ions, thus affecting removal efficiency. Therefore, in practical applications, the composition complexity of wastewater needs to be considered.

The above is the whole content of this article, polymerized iron sulfate as a funny water treatment agent, can solve the problem of excessive heavy metals in sewage, if you encounter any problems in the use of the process, welcome to contact us at any time, we will be happy to serve you.