Recover nutrients such as ammonium and phosphate through selective adsorption using functionalized MOFs..pptx

Recover nutrients such as ammonium and phosphate through selective adsorption using functionalized MOFs.
Recover valuable metals (e.g., gold, copper) from industrial wastewater streams using MOF-embedded membranes with affinity for specific ions.

1. Recover nutrients such as ammonium and phosphate through selective adsorption using functionalized MOFs. Presenter （ 主持人） : Riaz Ahmad 2024-12-18

2. Contents Academic Timeline Research Overview Selected Publications and Recent Research Future Research Plan

3. Sustainable Production Food, Energy and Environment Security System Evaluation Up to 5.5 billion people worldwide could be exposed to polluted water by 2100 (1) . Currently, 80.0% of global wastewater is released into environment without treatment (2) . Typical pollutants are nitrates, trace heavy metals (Pb, Cd, Cr, Ni, Zn, As, Hg, etc.), artificial sweeteners, hormones, pesticides, pharmaceuticals, surfactants, steroids, endocrine disrupting compounds and personal care products etc. (3) . China is also facing the issue of water pollution. Background 研究背景 (1) Nature, 2023, Water pollution ‘timebomb’ threatens global health, simulations predict a water-pollution crises by the end of the century. (2) World Health Organization (WHO), 2022, Wastewater Management. (3) Springer-Sensors in Water Pollutants Monitoring: Role of Material, 2019, Types of Water pollutants: conventional and Emerging.

4. Background 研究背景 Water treatment! Why? Water requires treatment to! O vercome water scarcity in China and worldwide, enhance the water security and conserve water resources. Remove pathogens, bacteria, viruses, parasites and the other contaminants. Protect the human health from the waterborne diseases i.e. cholera, typhoid, dysentery etc. Maintain the environmental quality, pollution prevention in waterways and protection of aquatic life. Increase the water reuse and recycling opportunities.

5. Background 研究背景 Treatment technologies used to remove pollutants from the liquid phase Membrane technologies Microfiltration Ultrafiltration Nanofiltration Reverse Osmosis Oxidation Oxidation and filtration Photochemical oxidation Photo catalytic oxidation Biological oxidation In situ oxidation Coagulation Flocculation Adsorption Activated carbon Activated alumina Iron based sorbents Zero valent iron Miscellaneous sorbents Ion exchange Pollutants treatment Adsorption: easy and green operation, regeneration . Disadvantages :U nable to Degrade the pollutants on the surface of adsorbents

6. Selected Publications N-Nitrosodimethylamine Removal by a Novel Silver/Sulfur-Coated Nanoscale Zero-Valent Iron/Activated Carbon Composite: Adsorption Kinetics, Mechanisms, and Degradation Pathways Objective & Highlights: Crystalline Ag and FeS -coated amorphous nZVI spheres were successfully supported on AC. Ag@S-nZVI /AC exhibited 9.89 times greater NDMA adsorption affinity than that of AC. A greater extent of NDMA degradation by Ag@S-nZVI /AC was achieved. Van der Waals force, hydrogen bond and surface-mediated electron transfer were dominated. Surface S 2– was transferred to bulk S 2– along with oxidation of S. Ahmad R., et al. Separation and Purification Technology. 2024, 354, 128923. SCI indexed. IF: 8.6 - Top Q1 in CAS & JCR ranking.

7. Main Findings SEM images & EDS analysis TEM image, HAADF and HRTEM image Finding a promising way of improving the adsorption capacity of nZVI/AC-based materials by coating them with metals. SEM, TEM, and HAADF results confirm the Ag and FeS -coated amorphous nZVI spheres were successfully supported on AC. The targeted pollutants were adsorbed on the surface of the composite, as confirmed by EDS results. Carbon TEM HAADF Fe S O Ag HRTEM AC nZVI/AC S-nZVI/AC Ag@S-nZVI /AC Treated

8. Main Findings XRD patterns, N 2 adsorption isotherms, pore distributions, FTIR analysis, and XPS surveys XRD results confirm the crystalline Ag and FeS -coated amorphous nZVI spheres BET results confirm the decrease in surface area after supporting nZVI, Ag, and S. The targeted pollutants were adsorbed on the surface of the composite, as confirmed by FTIR results. XPS confirm crystalline Ag and FeS coated amorphous nZVI spheres were supported on AC without largely changing porous structure of AC.

9. Main Findings Comparisons of NDMA removal rate under different nS:nFe , Ag content Effect of pH on NDMA removal efficiency fitting to PFO, PSO, and Elovich models Influence of pH is passivation of Fe and Ag surface in Ag@S-nZVI /AC under an alkaline condition, which might impede electron transfer and the generation of hydrogen radicals resulting in reduced removal efficiency

10. Main Findings Effect of initial concentration on NDMA removal efficiency, fitting to PFO, PSO, and Elovich , NDMA adsorption isotherm fitting to the Langmuir isotherm model, the Freundlich isotherm model, the thermodynamic model. Effect of ethanol, salts on NDMA removal, NDMA degradation mechanism, Fe 2p, O 1s, S 2p, and Ag 3d XPS survey in the raw composite and the treated composite. NDMA removal under neutral conditions involves physicochemical heterogeneous adsorption. Furthermore, values of k 1 , k 2 and α decreased with increasing initial concentration of NDMA.

11. Metal leaching concentration & NDMA removal efficiency Regeneration tests Main Findings Metal leaching amounts are lower than the EPA-recommended maximum levels for drinking water (0.1 mg L –1 for silver and 0.3 mg L –1 for iron). The physically regenerated sample exhibited higher adsorption efficiencies than the chemically regenerated sample. Additionally, the physical regenerated sample exhibits lower decrease in adsorption efficiency with increasing regeneration time than the chemically regenerated sample.

12. Main Findings Schematic of interfacial behavior and degradation mechanism of NDMA by Ag@S-nZVI /AC NDMA was adsorbed on Ag@S-nZVI /AC and then was reduced to DMA, NO 3 - , NO 2 - , and NH 4 + through a surface-mediated electron transfer process.

13. One-step synthesis of reduced graphene oxide/activated carbon composite for efficient removal of per- and polyfluoroalkyl substances from drinking water: Adsorption mechanism and DFT study Selected Publications Objective & Highlights: Lyophilization of waste cassava peels was successfully applied as a cross-linking agent. RGO/AC composite was synthesized by in-situ steam activation of graphene oxide/biochar. Supported GO-enhanced activation process of BC, development of pores, and hydrophobicity. Van der Waals force, hydrogen bond and surface-mediated electron transfer were dominated. Both short- and long-chain PFAS adsorption performance were enhanced by RGO/AC. Ahmad R., et al. Chemical Engineering Journal. Manuscript ID. 24-40813-Under review. SCI indexed. IF: 13.1 - Top Q1 in CAS & JCR ranking.

14. Main Findings Scheme of one-step synthesis of RGO/AC Physical expression of cross-linked GO/BC with fermented cassava (a) and lyophilized peels (b)

15. Main Findings XRD patterns (a); N 2 adsorption isotherms (b); Raman spectra (c); SEM images (g); contact angles; FTIR analysis (j). Pore distributions of RGO/AC composites; (conditions, the ratio of GO and AC, 0.2, 0.4, 0.6, 0.8) The diffraction peaks in XRD pattern of post-treated AC and RGO/AC significantly moved from higher to lower 2θ, which resulted in the appearance of diffraction peaks at around 18-22° 2θ and 39-43° 2θ From the BET results the hysteresis loops in isotherm curves of AC and RGO/AC from p/p0 ranged from 0.4 to 1.0, confirming mesopores in the adsorbents From Raman results the obvious peaks located at 1353.12 and 1609.30 cm −1 indicate D and G peaks

16. Main Findings Effects of initial solution pH on PFAS removal Pseudo-first-order and Pseudo-second-order kinetic fitting curves of PFAS adsorption Effect of adsorbents dosage on PFAS adsorption efficiency; comparison of PFAS adsorption efficiency by RGO/AC synthesized under different steam injection rate

17. Main Findings Effect of temperature and the initial concentration on PFOS, PFOA, PFBS, and PFBA removal Thermodynamic study indicated an exothermic and spontaneous process of PFAS adsorption on RGO/AC composites. Thermodynamic study

18. Main Findings Reduction extent of PFAS removal efficiency Comparison of PFAS adsorption efficiency of different adsorbents The pH PZC value of AC and RGO/AC Effect of coexisting ions on PFAS removal PFAS removal efficiency decreased with increased concentrations of Cl – , NO 3 – and humic acid (HA).

19. Chemical (a) and physical regeneration (b) of RGO/AC; PFAS removal performance of RGO/AC in real PFAS-spiked tap water EDS of utilized RGO/AC for PFOS for PFOA, PFBS, PFBA Main Findings PFOS PFBS PFOA PFB A

20. Main Findings Adsorption energy calculation on active sites for RGO/AC and AC The HOMO and LUMO of the PFOS, PFOA, PFBA and PFBS The HOMO is typically situated on the C–C backbone of the alkyl chain with significant electron density distributed around the C atom. The LUMO is mainly located on the F atoms because of their high electronegativity, which enhances their electron-accepting ability. COOH–RGO group and AC have minimum negative adsorption energy of -1032.799 eV and -1030.416 eV.

21. Main Findings The adsorption energy calculations (Eads) of PFOS, PFOA, PFBS and PFBA over different adsorption models of RGO (COOH, OH, Defects, Sp2 and Epoxy) and AC (carbonyl and carboxyl) To estimate the theoretical adsorption distance, the adsorption locator model was used by material studio software having an initial adsorption distance of 10 Å over the different adsorption models of RGO/AC (COOH, OH, Defects, Epoxy, Sp 2 -C, Carbonyl and Carboxyl). After simulations, all adsorption models showed that adsorption distance was shorter than the given initial distance.

22. Main Findings FTIR, XPS surveys, and percentage of different splitting carbon of treated RGO/AC composites; Fine XPS spectra of fresh AC, fresh RGO/AC, RGO/AC treated by PFOS adsorption Plausible mechanisms for both short and long-chain PFAS removal by the RGO/AC composite

23. Future Research Development of High-Performance Metal-Organic Framework (MOF)-Based Membranes for Sustainable Wastewater Treatment and Resource Recovery Research Objectives Design and fabricate high-performance MOF-incorporated membranes with enhanced permeability, selectivity, and fouling resistance. Engineer functionalized MOFs for specific applications, such as heavy metal removal, nutrient recovery, and organic micropollutant degradation. Investigate resource recovery mechanisms to reclaim valuable nutrients (e.g., nitrogen, phosphorus) or metals from wastewater. Develop cost-effective and scalable membrane fabrication techniques for industrial applications.

24. MOFs in Water Treatment Background 研究背景 MOFs possess a highly ordered structure of metal nodes and organic linkers, providing adjustable pore sizes, high chemical versatility, and selectivity for various pollutants. Recent studies have shown promising applications in adsorptive and catalytic wastewater treatment. However, challenges such as MOF stability in water and integration into membranes remain to be fully addressed

25. Future direction Surface modification of graphene oxide for fast removal of organic/inorganic pollutants from wastewater GO exhibits high susceptibility to surface modifications due to its chemical reactivity.

26. Methodology Fabrication of MOF-Based Membranes MOF Selection and Synthesis: Select water-stable MOFs (e.g., ZIF-8, UiO-66, MIL-101) with tailored pore structures for specific contaminant separation. Functionalize MOFs with chemical groups to enhance adsorption or catalysis. Membrane Integration: Fabricate mixed-matrix membranes (MMMs) by embedding MOFs in polymer matrices (e.g., PVDF, PES). Develop thin-film nanocomposite (TFN) membranes by depositing MOF layers on support membranes. Surface Modification: Use plasma treatment, grafting, or layer-by-layer assembly to improve hydrophilicity and antifouling properties.

27. Performance Testing Filtration Tests Fouling Studies Long-Term Stability Measure permeability, selectivity, and rejection rates for heavy metals, nutrients, and organic micropollutants. Evaluate antifouling properties under conditions mimicking industrial wastewater . Test membrane durability in extreme pH, temperature, and salinity conditions.

28. Resource Recovery Investigations Recover nutrients such as ammonium and phosphate through selective adsorption using functionalized MOFs. Recover valuable metals (e.g., gold, copper) from industrial wastewater streams using MOF-embedded membranes with affinity for specific ions.

29. Thank you for your attention Questions are welcome