Study of cyanide removal from contaminated water using zinc peroxide nanomaterial

The present study highlights the potential application of zinc peroxide (ZnO₂) nanomaterial as an efficient material for the decontamination of cyanide from contaminated water. A process patent for ZnO₂ synthesis has been granted in United States of America (US Patent number 8,715,612; May 2014), South Africa, Bangladesh, and India. The ZnO₂ nanomaterial was capped with polyvinylpyrrolidone (PVP) to control the particle size. The PVP capped ZnO₂ nanomaterial (PVP-ZnO₂) before and after adsorption of cyanide was characterized by scanning electron microscope, transmission electron microscope, X-ray diffractometer, Fourier transform infrared spectroscopy and time of flight-secondary ion mass spectrometry. The remaining concentration of cyanide after adsorption by PVP-ZnO₂ was determined using ion chromatograph. The adsorption of cyanide over PVP-ZnO₂ was also studied as a function of pH, adsorbent dose, time and concentration of cyanide. The maximum removal of cyanide was observed in pH range 5.8–7.8 within 15 min. The adsorption data was fitted to Langmuir and Fruendlich isotherm and it has been observed that data follows both the isotherms and also follows second order kinetics.