Synthesis and Shaping Scale-up Study of Functionalized UiO-66 MOF for Ammonia Air Purification Filters

Abstract

We report herein the upscaled synthesis and shaping of UiO66-COOH for NH3 air purification. The synthesis of the zirconium-based MOF was carried out in a batch reactor in an aqueous suspension with a yield of 89% and a spacetime yield of 350 kg/day/m 3. Neither toxic chemicals nor organic solvents were used, allowing this MOF to be employed in individual or collective air purification devices. Freeze-granulation and extrusion shaping techniques were investigated. The NH3 air purification performances of UiO66-COOH in bead, tablet and extrudate forms were compared to those of commercial carbon based materials (type K adsorbents from3M and Norit). Testing conditions were chosen to reflect current standards for ammonia concentration (600-1200 ppm) and velocity. In addition, the breakthrough measurements were carried out at three different relative humidity levels (0%, 40% and 70%). Pellets and extrudates of UiO66-COOH outperformed commercial benchmark adsorbents in all conditions, especially in dry conditions, for which the commercial adsorbents suffered impaired ammonia uptake and shortened service life. Extrudates of UiO66-COOH also withstood attrition after intensive shaking.

Recent advances in process engineering and upcoming applications of metal–organic frameworks

“…Before S. A. After Process time Ref Polyvinyl group MIL-125-NH 2 97% 1259 930 – [154] Polyvinyl alcohol (PVA) UiO-66 22 vol% 710 359 30 min [155] Polysiloxane UiO-66 72.5 vol% 710 418 30 min [155] Polyvinyl Butyral (PVB) SIFSIX-3-Ni – 360 297 – [156] Polyvinyl Butyral (PVB) SIFSIX-2-Cu-i – 808 685 – [156] Polyvinyl Butyral (PVB) GeFSIX-2-Cu-i – 755 659 – [156] Polyvinyl Butyral (PVB) TIFSIX-2-Cu-i – 740 719 – [156] Polyvinyl Butyral (PVB) Mg-MOF-74 – 915 – – [156] Polyvinyl Butyral (PVB) HKUST-1 – – – – [156] Polyvinylchloride (PVC) ZIF-8 7.5 / 15 / 30 wt% – – – [157] Polyvinylformal (PVF) ZIF-8 7.5 / 15 / 30 wt% – …”

“…Before S. A. After Process time Ref Binder-free MOF-5 – 2750 2600 ~ 1200 – [166] CPO-27-Ni – 1060 1050 30 min [167] CuBTC (Basolite™ C300) – – – – [168] MIL-53(Al) – – – – [168] HKUST-1 – – – 3 h [169] UiO-66 – 1175 511 / 417 6–18 h [155] HKUST-1 – – – 11 h [170] ZIF-8HT – – 1387 1 d [170] ZIF-8LT – – 1359 1 d [171] ZIF-8LT-HT – – 1423 1 d [171] ZIF-8ER – – 1395 1 d [171] …”

“…Shaping using polymer-type binders has been the most widely studied. Specifically, polymer binders with polyvinyl groups such as Polyvinyl group [154] , [155] , [156] , [157] , polyetherimide (PEI) [157] , polystyrene (PS) [157] , cellulose-acetate (CA) [157] , acrylonitrile butadiene styrene [158] , sucrose [159] and TENAX [160] have been combined with MOFs for shaping. Typically, polymer binders are the first choice for MOF shaping because i) they are easy to dissolve in volatile dispersion media, making mixing and drying of the MOF powder relatively simple; ii) they have various chemical bonding groups, and thus the degree of interaction between the chemical functionalities and dangling components of the MOF particles can be controlled; iii) there are many precedents for the use of polymers as binders with other classes of porous materials, such as activated carbon and zeolites, which increases the probability of shaping success; and iv) compared with inorganic binders, organic binders have relatively low weights, and thus the weight of the binder required for shaping is low, which is advantageous in terms of performance per unit weight.…”

Supercritical Fluid‐Facilitated Exfoliation and Processing of 2D Materials

“…[53,72,151,152] High rotation speeds of a shear mixer usually mean large shock velocities of SCF molecules parallel to the sheets. [53,72,151,152] High rotation speeds of a shear mixer usually mean large shock velocities of SCF molecules parallel to the sheets.…”

“…As an alternative to ultrasound, mechanical shear also can help accelerate exfoliation of layered materials in SCFs . High rotation speeds of a shear mixer usually mean large shock velocities of SCF molecules parallel to the sheets.…”