LAUSR

Abstract Aromatic amines (AA) are a group of industrial and environmental pollutants with high thermodynamic stability and carcinogenicity. Their toxicity has raised concern worldwide and calls for the development of effective elimination methods based on nanomaterials. Recently, the high adsorbing and photocatalytic efficiency of widely used metal hexacyanoferrates was observed. To confirm this, potential of potassium zinc hexacyanoferrate (ZnHCF) and potassium copper hexacyanoferrate (CuHCF) were evaluated in remediation of simulated water containing selected hazardous AAs. Highly crystralline and sharp nanocubes of ZnHCF (∼50 nm) and distorted nanocubes of CuHCF (∼100 nm) were synthesized via green route using sapindus mukorossi (raw ritha) as a biosurfactant. Under optimized conditions—concentration of amine(1.0 × 10 −4  M), catalyst (25 mg) and neutral pH, ZnHCF was found better with maximum degradation efficiency (90% of p-anisidine, 76% of p-toluidine, 71% of aniline and 70% of p-chloroaniline) followed by CuHCF (88%, 72%, 69% and 64%, respectively). This might be because of its higher zeta potential and BET surface area of ZnHCF. The highest adsorption (%) of p-anisidine on acidic surface of catalysts is probably due to its highest basicity. Statistical treatment of data fitted to various adsorption isotherms indicated the monolayer adsorption of AAs over surface of catalyst i.e., Langmuir with highest regression coefficient values (R 2 more than 0.98 for all AAs). GC–MS analysis confirmed the formation of small, non-toxic by-products such as benzoquinone, hydroquinone, but-2-enal, 4-oxobut-2-enoic acid and malealdehyde. The potential of MHCF nanoparticles can be explored more effectively in removal of organic pollutants for solving the water pollution problems.