There are very many impurities contained in industrial wastewater. The common impurity we see is sulfuric acid. In fact, not only sulfuric acid, but the existence of nickel is also very common. When we deal with industrial wastewater, we need to consider how to deal with nickel. If the nickel content does not meet the standard, the sewage cannot be discharged normally.
Sodium hydroxide manufacturers generally suggest that users use sodium hydroxide for precipitation, and then through PAC coagulation, PAM flocculation, and the precipitated water can be discharged. From a chemical point of view, it is to use sodium hydroxide to adjust the pH value of the wastewater, but due to the presence of complexing agents in the chemical nickel, hydroxide ions cannot form a precipitate with nickel ions. What is a complexing agent?
Complexing agents mainly refer to citric acid, tartaric acid, malic acid, lactic acid, etc. They combine with nickel ions to form small molecules. The complexed small molecules are very stable in the wastewater. Using sodium hydroxide, sodium sulfide, liquid heavy metal capture agent or solid heavy metal capture agent cannot destroy the combination of complexing agent and nickel ions, so nickel ions are difficult to remove.
If it is necessary to remove nickel, sodium hydroxide manufacturers still suggest using it in combination with a nickel removal agent. The nickel removal agent contains a large number of nickel removal groups, which will deform under microscopic conditions and form a negative charge field on the surface, thereby adsorbing nickel ions to form a precipitate, so as to achieve the effect of nickel removal when it is stable and up to the standard.
