Metal-Organic Frameworks and Porous Polymer Networks for Carbon Capture

Transcription

1 Carbon Capture Workshop, Tuesday, April 3 rd, Texas A&M, Qatar Metal-Organic Frameworks and Porous Polymer Networks for Carbon Capture J. P. Sculley, J.-R. Li, J. Park, W. Lu, and H.-C. Zhou Texas A&M University

2 Contents 1. Introduction 2. From MOPs to MOFs 3. MOFs for CO 2 Storage/Separation 4. SRMOFs for Gas Separation 5. PPNs for CO 2 Separation MOPs = Metal-Organic Polyhedra MOFs = Metal-Organic Frameworks SRMOFs = Stimuli-Responsive MOFs PPNs = Porous Polymer Networks

3 Designing Metal Nodes and Organic Linkers in Synthesis MOPs construction MOFs construction

4 Applications of MOPs and MOFs Gas Storage CO 2 Capture Separation Catalysis Drug Delivery

5 Post-Combustion CO 2 Capture 1.0 ton Coal ~ 2.5 tons CO 2 Flue Gas 12% CO 2 74% N 2 12% H 2 O 4% O 2 STEAM Emission Control SO 2, NO x, Hg, Particulate WATER CO 2 Capture Coal* 50% C 20% H 2 O 12% O 2 5% Ash 3% H 2 (S, Hg) Air 78% N 2 21% O 2 *Coal composition varies greatly with grade and source. Purified CO 2 to Storage Regeneration

6 MOFs for Carbon Capture and Storage How do we selectively sequester CO 2 in high-uptake materials that are low cost, nontoxic, and water stable? (1) increasing CO 2 uptake by generation of MOFs with even higher surface areas and larger pore volumes by the use of larger bridging ligands or highly connected secondary building units (SBUs) (1) increasing the selectivity of MOFs through enhancement of the adsorption enthalpies for CO 2 through decoration of the materials The small kinetic diameter of CO 2 (3.3 Å) High quadrupole moment of CO 2

7 Contents 1. Introduction 2. From MOPs to MOFs 3. MOFs for CO 2 Storage/Separation 4. SRMOFs for Gas Separation 5. PPNs for CO 2 Separation MOPs = Metal-Organic Polyhedra MOFs = Metal-Organic Frameworks SRMOFs = Stimuli-Responsive MOFs PPNs = Porous Polymer Networks

8 Bridging-angle modulated MOPs Various polyhedra Metal nodes (Cu, Ru, Mo, Zn, Rh, ) Designed organic ligands with prefixed bridging geometry Assemblies of various angular linkers with a square four-connected node

9 The Mo 2 (O 2 C ) 4 cluster and dicarboxylate linkers with different bridging angles, sizes, and non-bridging functional groups.

10 Metal-Organic Cuboctahedra JACS, 2010, 123,

11 Metal-Organic Octahedra JACS, 2010, 123,

12 Bridging-ligand substitution Synthetic strategy based on the substitution of bridging ligands in soluble MOPs The introduction of linkers with different properties from those of the initial MOP can thus lead to new MOP with distinct properties Partial substitution can also occur and form mixed-ligand species Nature Chem., 2010, 2, 893.

13 Selective Gas Adsorption of MOPs 80 V ads (cm 3 /g, STP) K N 2 ads H 2 ads P /mmhg Activated sample (MOP-1) V ads (cm 3 /g, STP) K CO 2 CH 4 10 amorphous P /mmhg Nature Chem., 2010, 2, 893.

14 Thermosensitive, Molecular-Sieving Effect Low Temperature Medium Temperature High Temperature Chem. Commun., 2010, 46, 7352.

15 Stepwise Synthesis of MOP-based MOFs JACS, 2009, 131, 6368.

16 Contents 1. Introduction 2. From MOPs to MOFs 3. MOFs for CO 2 Storage/Separation 4. SRMOFs for Gas Separation 5. PPNs for CO 2 Separation MOPs = Metal-Organic Polyhedra MOFs = Metal-Organic Frameworks SRMOFs = Stimuli-Responsive MOFs PPNs = Porous Polymer Networks

17 One-pot Synthesis of MOP-based MOFs PCN-6X Stabilization of Metal-Organic Frameworks with High Surface Areas by the Incorporation of Mesocavities with Microwindows JACS, 2009, 131, 9186.

18 MOFs with Higher Surface Areas and Larger Pore Volumes Material BET area (m 2 /g) CO2 uptake at 35 bar and 298 K (mmol/g) PCN PCN PCN The surface area of the activated MOF has been increased remarkably by ligand extension, presumably due to the increased size of the mesocavities PCN-61 PCN-66 PCN-68 Angew. Chem. Int. Ed. 2010, 49,

19 CO 2 Uptakes of PCN-6X At 35 bar and room temperature, a container filled with PCN-61 can store 8.2 times the amount of CO 2 in an empty container This volumetric capacity is 7.3 for PCN-66 and 7.4 for PCN-68 PCN-6X series are good sorbents for carbon dioxide 19

20 CO 2 Loading and CO 2 /N 2 Selectivity based on Breakthrough Measurement 1 C/C o q yqtp y VP RT RT f f t s f T b b s m c b (1 ) T b b p t t 0 t b 1 c c o t c dt CO 2 / Time N 2 q CO q N 2 2 y y CO N 2 2 The packed bed porosity b The particle porosity y f The mole fraction of CO2 Q The volumetric feed flow rate t f t The stoichiometric time T Vb p The total porosity The volume of the bed J. A. Ritter et al., Proceedings of the 2002 ASEE Annual Conference

21 Results of Breakthrough Measurements - Simulated PCN-61 flue Breakthrough gas: 10% curve CO 2 & 90% N 2 - RT, PCN C/Co Carbon dioxide Nitrogen Time (min) q CO2 = 0.24 mmol/g q N2 = 0.14 mmol/g S = 15.4

22 Contents 1. Introduction 2. From MOPs to MOFs 3. MOFs for CO 2 Storage/Separation 4. SRMOFs for Gas Separation 5. PPNs for CO 2 Separation MOPs = Metal-Organic Polyhedra MOFs = Metal-Organic Frameworks SRMOFs = Stimuli-Responsive MOFs PPNs = Porous Polymer Networks

23 Why Stimuli-Responsive MOFs? Metal-organic frameworks better than conventional sorbents: possible to design/engineer Stimuli-responsive MOFs based on adjustable kinetics that are not available with other framework materials such as zeolites Molecular gates D(T) S. Ma, et al., ACIE 2007 & JACS 2009 Energy N 2 N 2 * Adsorption CO 2 CO 2 * Reaction Coordinate Stimuli (T, h, ) Energy N 2 N 2 * CO 2 CO 2 * Reaction Coordinate Reverse Stimuli (T, h, ) Desorption Energy CO 2 CO 2 * Reaction Coordinate

24 Mesh Adjustable Molecular Sieves (MAMS) 24 When the size disparity of the two gases that need to be separated is very small, a molecule sieve with the precise mesh size is not always readily available. In such cases, a meshadjustable molecular sieve (MAMS) that can always meet the separation needs is highly desirable The strategy for the assembly of a MAMS is to construct graphitic MOFs using amphiphilic ligands and metal nodes. In these structures, the gate opening can be tuned by changing temperature (type A) or pressure (type B) Schematic representation of two types of MAMS Metal-containing node and organic linker for the construction of MAMS Structural units in MOF based MAMS with dicarboxylate ligands and Cu 2 paddlewheel units

25 Temperature Responsive in MAMS-1 25 Zhou et al. Angew. Chem., Int. Ed. 2007, 46, 2458.

26 Stimuli Responsive Functional Groups 300~400 nm Length : 9.0 Å 5.5 Å π π* transition Kumar, G. S. Chem.Rev. l989, 89, n π* transition UV Vis or 26

27 Optically Sensitive MOFs UV Heat trans vs. cis Accessible pore size, surface area, and polarity change 27 Considerations Framework size + functional group size

28 MOF Design and Synthesis DEF + Zn(NO 3 ) 2 85 MOF 5 type crystal 28 J. Am. Chem. Soc. 2012, 134 (1),

29 Photoresponsive CO 2 Adsorption cm 3 /g cm 3 /g cm 3 /g 29

30 Reversible CO 2 Adsorption 30

31 Contents 1. Introduction 2. From MOPs to MOFs 3. MOFs for CO 2 Storage/Separation 4. SRMOFs for Gas Separation 5. PPNs for CO 2 Separation MOPs = Metal-Organic Polyhedra MOFs = Metal-Organic Frameworks SRMOFs = Stimuli-Responsive MOFs PPNs = Porous Polymer Networks

32 Porous Polymer Network (PPN) Disadvantages: Difficult to characterize No Metals Limited synthetic routes Advantages: Covalent bonds High surface area High gravimetric uptake Extremely low density High thermal stability Chemical stability Chem. Mat. 2010, 22,

33 Comparison of the networks PPN 3 PPN 4 PPN 5 PAF 1 BET (m 2 g 1 ) SA calc * Langmuir (m 2 g 1 ) Pore volume (cm 3 g 1 ) *The accessible surface area is calculated from a simple Monte Carlo integration technique where the probe molecule is "rolled" over the framework surface 33

34 Hydrogen uptake TAMU PPN-4 Excess Concentration (wt.% H) Isotherm: 77 K Run 1, Adsorb Run 1, Desorb Run 2, Adsorb Run 2, Desorb Model Fit 95% CI Pressure (bar) Results from SWRI (Michael Miller and Carol Ellis) 34

35 Synthesis of PPN 6 and Modification 35

36 Postsynthetic Modification Network BET SA (m 2 /g) Pore width (Å) Pore Volume (cm 3 /g) PPN PPN 6 SO 3 H PPN 6 SO 3 Li

37 295K CO 2 uptake Network CO 2 uptake (cm 3 /g) CO 2 uptake (mmol/g) CO 2 uptake (wt%) CO 2 uptake (g/kg) Tap density (g/cm 3 ) CO 2 uptake (g/l) PPN PPN 6 SO 3 H PPN 6 SO 3 Li

38 Isosteric heats of adsorption 38

39 IAST predicted adsorption selectivities Dr. Rajamani Krishna 39

40 Conclusions MOFs, MOPs, and PPNs are materials with a bright future The syntheses of MOPs and MOFs can be well controlled MOFs have extraordinary potential in gas storage SRMOFs are excellent for gas separation PPNs has potential for gas storage/separation

41 41 Acknowledgments