A Three-Dimensional Porous Organic Framework for Highly Selective Capture of Mercury and Copper Ions

Abstract

In this study, a crystal porous organic framework (POF) belonging to ctn topology (POFct-1) is synthesized to selectively scavenge Hg(II) and Cu(II) ions. The maximum adsorption capacities of 167.19 mg g −1 and 135.60 mg g −1 are achieved toward Hg(II) and Cu(II) ions, respectively. In addition, the Langmuir isotherm model plus pseudosecond-order kinetic model for Hg(II) and Cu(II) ions can well describe the adsorption process of POFct-1. After five repeated uses, POFct-1 still exhibits high adsorption capacities. Conversely, a POF in amorphous form (POFct-2) is synthesized by changing the pressure and atmospheric conditions. The distribution coefficients of Cu (II) ions for the crystal (POFct-1) and amorphous (POFct-2) forms are 1.01 × 10 5 and 5.93 × 10 2 mL g −1 in a single ion solution, respectively. These results indicate that the POF in crystal form exhibits increased adsorption selectivity toward Cu(II) ions. The diverse structures and performances of POFs present them as promising candidates in selective adsorption of heavy metal ions.

Multifunctional Polyhedral Oligomeric Silsesquioxane (POSS) Based Hybrid Porous Materials for CO2 Uptake and Iodine Adsorption

“…The preparation of porous organic polymers (POPs) has become a hot topic in the academic and industry fields due to their interesting features, such as high physicochemical stability, porous character, low density, facile preparation, low regeneration energy, and good thermal and chemical stabilities [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. Porous organic polymers have been applied in different applications such as light harvesting, chemical sensors, catalysis, iodine uptake, H 2 production from water, water treatment, optoelectronic devices, carbon dioxide reduction, nanofiltration, enantioseparation, energy storage, gas separation, and adsorption [ 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ]. The synthesis of POPs was successfully achieved using various synthetic methods, including Friedel–Crafts arylation, Schiff base reactions, Suzuki reactions, Yamamoto reactions, Heck reactions, and Sonogashira reactions [ 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ].…”

Orderly Porous Covalent Organic Frameworks-based Materials: Superior Adsorbents for Pollutants Removal from Aqueous Solutions

“…In addition, the large amount of oxygen and nitrogen in the skeleton of TpODH has strong electrostatic synergy and coordination for metal ions, i.e., Hg 2+ (1,692 mg·g −1 ) and Cu 2+ (324 mg·g −1 ). A 3D porous organic framework (POFct-1) with topological structure has been used to selectively remove Hg 2+ and Cu 2+ , 51 and its color changes in the presence of hydrogen ions and visible light. The O-containing and N-containing functional groups of POFct-1 effectively adsorb Hg 2+ and Cu 2+ with adsorption capacities of 167.19 mg·g −1 (Hg 2+ ) and 135.60 mg·g −1 (Cu 2+ ).…”

“…These advantages, together with the characteristics of predesigned structure, ordered porous structure, and adjustable physicochemical properties, make COFs promising next-generation materials with remarkable high sorption capacities for radioactive/toxic metal ions and organic contaminants. 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , 102 , 103 , 104 , 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112 …”

Covalent Organic Frameworks: Synthesis, Properties and Applications—An Overview

“…Adsorption capacities of other heavy metals have also been reported, namely ions frequently found in industrial wastewater such as Cd(II) [ 84 , 85 , 86 ], Cr(VI) [ 87 , 88 , 89 ], Cu(II) [ 90 , 91 ] or Pb(II) [ 92 , 93 ], as well as Au(III) [ 94 ], lanthanides [ 95 ] and others [ 96 , 97 , 98 , 99 , 100 , 101 , 102 , 103 ].…”