Heavy metal removal from waste waters by phosphonate metal organic frameworks

Abstract

Abstract:The increase attention in the area of phosphonate metal organic framework is exemplified with a variety of applications and a rich chemistry of these compounds. Water pollution caused by heavy metal ions is a major concern due to their toxicity to many life forms. In order to decrease the heavy metals impact upon the environment various technologies of water treatment such as: chemical sedimentation, ion exchange, redox process are studied. The tendency is to find a versatile and economical method of heavy metals removal from waste waters. Phosphonate metal organic frameworks were obtained by the reaction of Ni(CH 3 COO) 2 · 4H 2 O, phosphonic acid (phosphonoacetic (CP), vinyl phosphonic acid (VP) and N,N-bis(phosphonomethyl)glycine (Gly)) in hydrothermal conditions. Coordination polymers synthesized were characterized by FTIR, XRD, scanning electron microscopy (SEM) and thermal gravimetric analysis (TGA). The adsorption processes represent a very good alternative for heavy metals removal due to low costs and ease of operation. In the present paper the adsorption performance of the mentioned materials in the removal process of heavy metals from aqueous solutions, was studied using the batch method. The adsorption conditions were investigated by varying the initial pH, contact time and adsorbate initial concentration for chromium metal ions removal from aqueous solutions. It was found that the adsorption efficiency of the studied materials in the removal process of Cr(VI) ions from aqueous solutions is in the following order: Ni-CP < Ni-Gly ≤ Ni-VP.

New Efficient Adsorbent Materials for the Removal of Cd(II) from Aqueous Solutions

“…Then the clear green or violet solution was heated in an oil-bath at 80 • C for 75 h, unperturbed. After 75 h heating crystalline green (Ni-Gly) and violet crystals (Co-Gly) materials precipitated and were isolated by filtration and finally air dried (yield: 52-75%) [27][28][29].…”

“…In the present paper, the use of two coordination networks based on cobalt and nickel were used as adsorbent materials in the removal process of cadmium ions from aqueous solutions. The structure, morphology, and properties of materials were investigated by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermal gravimetric analysis (TGA), which were previously described [27,28]. Inspired by these adsorption properties, we performed PM3 semiempirical analyses of structural properties to predict and understand better some special properties of these compounds.…”

Adsorption Study of Lead Ions on Nickel-Metal Organic Framework

“…The pH of the solution has an influence on the surface properties of the adsorbent and also on the ionic form of the metal solutions [16]. Hence this is the most important parameter for assessing the adsorption capacity of an adsorbent for metal ion removal from aqueous medium.…”

Hybrid Coordination Networks for Removal of Pollutants from Wastewater

“…MOFs are promising materials for applications in separation, adsorption catalysis [ 21 , 22 , 23 , 24 ], drug delivery agents, gas storage, corrosion, molecular recognition [ 25 ], antibacterial agents [ 26 ], sensors, and so on [ 27 , 28 ] because of their designable framework structures; the size, dimensions, shape, and surface functionality of the nanochannels can be tuned by changing the combination of metal ions and organic ligands.…”