Efficient removal of Cd (II) from contaminated water and soils using nanoparticles from nitrogen fertilizer industry waste 05 Environmental Sciences 0503 Soil Sciences

Abstract

Background: Cadmium (Cd) is used extencively in many industries and can cause environmenal pollution and severe damage to human health. As millions of tons of lime-based solid by-product from nitrogen fertilizer industry (NFIB) are produced each year, the main purpose of this study was to develop a novel, efficient and cheap nanoscale sorbent from NFIB for remediation of Cd (II) contaminated soil and water to protect and preserve public and ecosystem health. Methods: A novel nanoscale adsorbent was developed from the nitrogen fertilizer industry byproduct (NFIB) and was characterized using X-ray diffraction(XRD) and scanning electron microscope (SEM). Batch sorption equilibrium and kinetic experiments were conducted to evaluate the efficiency of nano- NFIB (nNFIB) in sequestering Cd(II) in contaminated soil and water. Results: The results of adorption equilibrium and kinetics experiments revealed that Langmuir and power function models best described Cd adsorption on bulk NFIB and nNFIB as evidenced by high R2(determination coefficient) and low SE(standard error of estimates) values. The Langmuir maximum adsorption capacity (q max) of nNFIB for Cd(II) was 100 mg g-1 which is twenty times higher than that of Bulk NFIB. The distinguishing features of NIFB nanoparticles involve efficient removal of Cd(II) from contaminated water (>90%) and enhancement of Cd (II) immobilization (146%) in cotaminated soil.Fourier Transmission Infrared (FTIR) spectra of Cd(II) contaminated water and soil before and after nNFIB application revealed the important rule of calcite nanoparticles in Cd(II) sequestration. Conclusions: The accessibility, low cost, and Cd sequestration efficiency of nNFIB nominate it to be an economic and a promised adsorbent for environmental remediation.