Why should cyanide wastes and chromium wastes be kept separate?

Cyanide wastes and chromium wastes should be kept separate because, when combined, they complicate the treatment process. Each type of waste has unique chemical properties and requires specific treatment methods to effectively remove the contaminants. If they are mixed, the effectiveness of standard treatment processes can be reduced, leading to potential environmental harm and regulatory compliance issues.

Cyanides are highly toxic and have specific treatment requirements, while chromium, depending on its form (trivalent or hexavalent), may require different methods for removal. When these wastes are treated together, their interactions can create challenges, such as forming stable complexes that do not allow for effective removal of either contaminant. Keeping them separate ensures that each type of waste stream can be treated using the most suitable and effective methods, thereby maximizing the removal efficiency and minimizing potential hazards.