Activated Carbon–Metal Organic Framework Composite for the Adsorption of Contaminants of Emerging Concern from Water

Abstract

A composite adsorbent (CMOF) based on in situ growth of MIL-100Fe (MOF) within the macro-and mesopores of a Darco-KB-G activated carbon (AC) was prepared for the efficient adsorption of a set of contaminants of emerging concern (CECs), namely, caffeine (CFN), carbamazepine (CBZ), clofibric acid (CA), 10,11-epoxycarbamazepine (Ep-CBZ), naproxen (NPX), o-desmethylnaproxen (o-DMN), paraxanthine (PXN), and salicylic acid (SA), from water. The properties of the composite and that of the parent materials were evaluated via X-ray diffraction, scanning electron microscopy, nitrogen porosimetry, thermal gravimetric analysis (TGA), and X-ray photoelectron microscopy. Mass balances indicate that the composite contains about 46 wt % MOF, while a comparison of pore size distributions and TGA corroborated that the vast majority of the crystalline material resides within the macro/mesopores of the AC. Zeta potential measurements revealed that the acid media used during the in situ growth of the MOF resulted in a CMOF surface charge profile (isoelectric point (IEP) = ∼3.2) that is generally more negative than that of the MIL-100(Fe) (IEP = ∼4.2) and the nonacid treated AC (IEP = ∼5.5). Single and multicomponent CEC equilibrium adsorption tests were performed at room temperature, neutral pH conditions, and low CEC concentrations (∼μg L −1 ). Single component adsorption data show that the composite adsorbs 10-fold more CEC molecules compared to the MOF alone, with a selectivity that increases as follows: CA < SA < o-DMN < PXN < NPX < CFN < Ep-CBZ < CBZ. The effect of competition among the CECs on the adsorption capacity of CMOF was not as significant, only about 9% smaller compared to single component adsorption data. Uptake improvements seen in the CMOF appear to be the result of interactions based on a combination of hydrophobicity (from the AC core) and enhanced electrostatic level forces as well as π-complexation and π−π stacking interactions.

UiO-66-NH2 and Zeolite-Templated Carbon Composites for the Degradation and Adsorption of Nerve Agents

“…As shown in Figure 1c, for U0.2Z0.8, the growth of small UiO-66-NH2 particles occurred on the surface of beta-ZTC. It has been reported that MOFs are located in the pores or void spaces of activated carbon in MOF-carbon composites [33]. However, in U0.2Z0.8, the UiO-66-NH2 nanoparticles were dispersed on the surface of beta-ZTC, likely because beta-ZTC has micropores with sizes between 0.7 and 1.0 nm.…”

Applications of Metal‐Organic Frameworks in Water Treatment: A Review

“…Carbon materials (CMs), such as graphene oxide (GO), [89] activated carbon (AC) [90] and carbon nanotubes (CNTs), [91] were extensively used in the preparation of substantial nanocomposites due to their porous characteristics and great chemical stability. [92] For instance, Co-Ni MOFs/3D graphene (Co-Ni c) Reproduced with permission.…”

Progress in the design of nanoporous adsorbent materials containing transition metals for the removal of contaminants of emerging concern

“…Muñoz-Senmache et al [69] have shown that it is possible to address the limitations of MOFs using the same in situ growth principle that was used for the preparation of CFAU hierarchical composites. Muñoz-Senmache et al successfully grew a MIL-100Fe MOF phase within the meso-and macro-pores of activated carbon (CMOF; Figure 5).…”

“…Fernández-Reyes et al tested the thermal regeneration of Cu 2+ -CFAU in a vacuum atmosphere, while Muñoz-Senmache, et al developed a thermal treatment of CMOF under nitrogen gas. Both adsorbents were tested for multi-cycle adsorption of naproxen Adsorbent materials: polymeric resin [71], linoptilolite [74], palygorskite [74], mesoporous silica (SBA-15) [53], copper amine-functionalized mesoporous silica (Cu-NH 2 _g_SBA-15) [53], hexagonal mesoporous silica (HMS) [61], aminefunctionalized hexagonal mesoporous silica (A-HMS) [61], mercapto-functionalized hexagonal mesoporous silica (M-HMS) [61], activated carbon (AC1) [61], cork [79], granular activated carbon coal-based Calgon Filtrasorbs 400 (F400) [78], coconut shell based PICACTIF TE activated carbon (CTIF-AC) [78], biochar [81], MIL-100Fe (MOF) [69], MIL-100Fe-activated carbon composite (CMOF) [69], activated carbon (AC) [56], detemplated FAU zeolite-activated carbon composite (CFAU) [56], and copper (II) containing FAU-zeolite/carbon composites (Cu-CFAU) [56]. and carbamazepine, respectively, and the results showed that the adsorption capacities remained constant even after three cycles.…”

“…Schematic representation of the assembly of hierarchical composite adsorbents (CFAU and CMOF). Adapted with permission from Muñoz-Senmache et al[69]. Copyright 2020 American Chemical Society.…”