Advanced materials synthesis and characterization facilities
The preparation of advanced materials with tailored properties for certain applications require careful understanding of the structure-property relationship of materials. This can be achieved by detailed characterization of material properties and finding the relation to performance. The advanced materials synthesis and characterization facilities at RICH is a multipurpose lab where materials can be synthesize and characterize for ad-hoc applications, covering not only the current areas of focus of the center, but also for other applications, including catalysis, removal of contaminants, water treatment, etc.
Some of the facilities and tools in the center related to advanced materials synthesis and characterization are listed as follows:
- Microreaction calorimeter: allows the analysis of heat capacity, heat of phase transition of liquid and solid sample, and heat of the reaction at different temperatures. Especially, it can work as a flow calorimeter to analyze heat of CO2 adsorption/absorption and CO2 loading simultaneously. It is equipped with a gas mixer to allow the analysis of a binary gas systems.
- Total Organic Carbon Analyzer (TOC): Analyze total organic and inorganic carbon, and total bound nitrogen in both liquid and solid samples.
- Sieve AS 200 shaker: It is used to analyze and classify particulate materials with particle size from 20 µm to 25 mm.
- Density meter: DMA 4500 M density meter measures the density of solutions at low and high pressures.
- Autoclave reactors for conventional and microwave growth of porous materials
- Lab Vacuum Oven (Thermo Fisher): Ambient to 300 °C, 50 L capacity. Dry up to six times faster than when using conventional units.
- Analytical balances
- Mechanical Ovens
- Vacuum oven: heating up to 200C at 0.01 mbar.
- Heating/stirring plates
- Tubular furnace
- Fourier Transform Infrared Spectroscopy: collect FTIR spectra using reaction chamber at temperature up to 910C and pressure of 133 mPa-133 kPa.
Fig. 1: Microreaction Calorimeter available at the Advanced Materials lab at RICH
Dedicated facilities for CO2 capture and H2 storage
Carbon dioxide emissions from different sources are considered a major contributor to the overall greenhouse gas emissions and global warming. Therefore, Carbon capture, Utilization and Storage (CCUS) has been recognized to contribute to reducing the CO2 emissions by 14-19%. This makes CCUS a very attractive technological option for carbon emissions reduction. Carbon capture and separation is the major element of the CCUS chain and could be integrated to different power generation and industrial systems. Even though, the conventional CO2 capture and separation technologies are well developed, these technologies have major challenges such as high-energy demand, limited capacity and high overall CO2 capture cost. As a strategic direction, the RICH center focuses on the development of advanced carbon capture technologies by investigating novel and more efficient materials and processes for CO2 capture. RICH activities in this area include emerging aqueous and organic solvents (DES, lean water, IL), novel solid adsorbents and hybrid systems.
Knowing that carbon management and hydrogen production are very closely connected, there is a growing interest in developing technologies for the carbonless production of H2 such as water splitting (electro- or photolytic) and H2S splitting. Although hydrogen has the highest energy per mass of any fuel, its low ambient temperature density results in a low energy per unit volume, therefore requiring the development of advanced storage methods that have potential for higher energy density. RICH works on establishing materials and processes for high-capacity, reliable-availability H2 storage including storage in porous media as well as evaluation of easily storable hydrogen carriers (e.g. ammonia).
In addition to the advanced materials facilities and other shared and core labs at KU, RICH has specific state of the art facilities tailored-made for CO2 capture and separation research and materials for H2 storage, including:
- Solvent Screening Setup (SSS): This set up consists of low pressure six parallel stirred tank semi batch (CSTR) reactors, designed to investigate the CO2 absorption performance. This performance is being evaluated by measuring the absorption capacity and the apparent rate of absorption. The set up offers a gas mixing system which could handle up to four different gases to simulate different gas streams and different CO2 partial pressures. In addition, it provides pressure, temperature, and flow rate control for each individual reactor. The gas stream is a continuous flow and the solvent is batch to be added to the 250 ml reactor.
- The Vapor Liquid Equilibrium (VLE): This set up consists of one single semi batch CSTR, which is used to measure vapor-liquid equilibrium of a solvent in details at different temperature, pressure and CO2 partial pressure. The size of the reactor of this system is 600 ml, which is larger than those for the SSS reactor. This will allow more accurate measurement of the VLE data at different conditions. In addition, the VLE system could go up to slightly high pressure (6 bar) and high temperature (130 oC) to allow measurement at CO2 desorption conditions.
- Packed bed reactor: Packed bed reactor was retrofitted to SSS system. This reactor is designed to test and evaluate the CO2 adsorption of a solid adsorbent for multiple CO2 adsorption-regeneration cycles.
- Stopped flow meter: The stopped flow meter is used to analyze the kinetics of reaction in the liquid phase. For example, reaction between amine solution and water dissolved CO The variation of conductivity over time will be used for kinetics analysis.
- Intelligent Gravimetric Analyzer (IGA)-ABR-DSMS: Dynamic modes sorption analyzer with integrated vapor generator and mass spectrometer. Breakthrough reactor & interface (working range: 0 to 500°C/ 10-6 mbar to 20 bar). The IGA can be used to determine both the equilibria and kinetics of sorption of real mixtures at a range of temperatures and pressures. Advanced Break through connected DSMS for breakthrough studies.
- 3 Flex Multiport Physisorption/Micropore Analyzer (Micromeritics, USA): Fully automated, high throughput, 3-port physical adsorption analyzer for high definition analytical measurement for the determination of specific surface area and pore size distribution.
Photocatalysis, a process by which a chemical reaction is accelerated via a light-induced catalytic material, is mainly used for the complete decomposition of organic pollutants commonly present in atmospheric air and industrial wastewater. Many successful real-life applications of photocatalysts have already been proven in enhancing the quality of both air and water. One example is self-cleaning coatings that have been integrated onto the surface of glass buildings. Other applications of photocatalysis include water splitting for the production of hydrogen and carbon dioxide reduction for the production of solar fuels.
The RICH center is primarily focused on investigating the application of photocatalysts for: (1) the conversion of CO2 and (2) the generation of H2. Due to the environmental concerns related to high atmospheric CO2 concentrations, photocatalysis is currently being explored as a promising solution for the reduction of CO2 into solar fuels, such as methane and methanol. Photocatalysis is also being studied for the production of hydrogen, a sustainable fuel resource, through the degradation of various water and air pollutants, including organic contaminants and H2S. In the RICH center, novel photocatalysts are first synthesized through wet-chemical techniques and are later characterized for their chemical, physical and optical properties. These photocatalytic materials are then tested for their application in CO2 conversion and H2 generation.
Some of the facilities and tools in the center related to photocatalysis are listed as follows:
- Sample preparation tools including Spin coater Chemate KW-4A equipped with hot plate, Nabertherm furnace Model L 5/11/P330, Thermo Scientific Heraeus™ Primo R Centrifuge refrigerated.
- Sample characterization tools including Shimadzu MODEL UV-2600. UV-Vis spectrophotometer equipped with reflectance accessory.
- Several photocatalytic reactors of different sizes and shapes that can operate in gas-phase or liquid-phase under controlled temperature and pressure conditions
- Variety of different light sources, ranging from UV to visible to solar, including Solar simulator by LOT-Quantum Design s.r.l.
- Gas and liquid chromatographs including Shimadzu Gas Chromatograph with FID Detector, Shimadzu Gas Chromatograph with TCD Detector, Thermo Scientific HPLC with Diode Array and Refractive Index detector.
RICH it is associated to the Masdar Institute Solar Platform, a unique environment where solar energy is coupled with different technologies at lab and pilot plant scale, including CO2 reduction and H2 production to make them more sustainable.
CO2 conversion to valuable products
Taking into account the reactivity of CO2 to minerals existing in specific wastes, the RICH center is working on the concept from waste-to-materials, in order to convert CO2, reacting with waste, into added value products. Work in progress at RICH is related to the utilization of steel slag and desalination brine wastes to convert CO2 into highly durable construction materials and into sodium bicarbonate. The current research interests of these projects are to study the crystal structure and the mechanical properties of steel slag and slag based construction materials upon accelerated mineral carbonation as well as optimizing the chemical process which uses desalination brine to convert CO2 into useful commercial products such as sodium bicarbonate.
Some of the facilities and tools in the center for CO2 conversion to construction materials and bicarbonates are:
- High pressure-high temperature reactors: SS 316, 1 L, up to 200 bar, up to 200°C non-stirred autoclaves: accelerated carbonation of slag based concrete blocks.
- Humidity chamber: -40 to 150 oC, construction materials pre-curing.
- Ofite compressive strength tester: 2” x 2” x 2” specimens, maximum press capacity: 16,000 lbs.
- Mortar Mixer ToniMIX: for mixing construction materials slurries
- Stopped flow meter SF-61SX2: meter helps analyze the kinetics of reaction in the liquid phase.
- Stirred reactors: 500 ml, carbonation of desalination brine into bicarbonates.
CO2 conversion by microalgae and waste valorization
CO2 utilization by microalgae for the production of valuable bio-based products including renewable fuels and nutraceuticals is one of the key strategic areas of the RICH Center. Detailed characterization is at the heart of the conversion processes because characterization guarantees high process performance efficiencies and product yields. The center is equipped with facilities for observing the microscale structure of microalgae and characterizing the carbohydrate, lipid, protein, and pigment contents of microalgae before extraction. Facilities for downstream processes such as centrifugation for harvesting, freeze drying for dewatering, and controlled/incubated shaking system for lipid/pigment extraction and transesterification are available. The center has a supercritical CO2 system for a more sustainable microalgal conversion to ensure low toxicity, easy product recovery, and operation at low temperatures.
The center is also equipped with tools for waste valorization. Tools for emerging trends in this area such as protein hydrolysate extraction from fish wastes, microalgal cultivation using food waste effluent, and oil spill sorption and recovery are available. The center also has pyrolysis and fermentation units for direct conversion of biomass and food wastes into biogas, bio-oil, biochar, and fermentation products. Food wastes and oil spill contribute considerably to global CO2 emissions.
Some of the facilities and tools in the center for CO2 conversion by microalgae and waste valorization are listed as follows.
- EVOS XL Cell Imaging Systems: Imaging live and fixed cells and culture determinations (density and growth).
- Pyrolysis unit: A horizontal tubular quartz reactor fixed inside an encapsulating furnace with digital temperature and inert gas flow rate controls.
- Bioreactor Fermentation unit: Acidogenesis of food wastes into volatile fatty acids. Equipped with temperature-, pressure-, pH-, agitation- and air flow rate-control.
- Lab Companion Incubated Shaker IST-3075 system: Temperature-controlled shaking. Cultivation of microalgae, downstream unit processes, fish waste hydrolysis, and crude oil sorption/herding/dispersion. Measurement of protein, carbohydrate, and lipid content through standard protocols such as Hartree-Lowry method, Phenol-Sulfuric Acid method, and Bligh and Dyer Method.
- OHAUS High Speed Centrifuge and TOPT-10A LCD display Freeze Dryer: Harvesting and dewatering of microalgae. Food waste protein drying after isolation or hydrolysis.
- Supercritical CO2 system: Lipid and carotenoid extraction, possible combined extraction-reaction process.
The supercritical CO2 system is also in used for other applications, including the synthesis of advanced materials.
The center also uses facilities in the Core Labs, including:
- FEI Quanta250 ESEM and FEI Nova Nano SEM 30 Series: The morphological characteristics of microalgae and oil sorbent samples are obtained using these microscopes.
- Witec Alpha 300R Raman Spectrometer: Raman signals with visible laser at a wavelength of 532 nm. The molecular arrangements in the chemical structures of protein wastes, oil sorbent and microalgae samples are compared using Raman spectroscopy.
- Bruker Vertex 80v FT-IR Spectrometer: Characterization of the functional groups in biomass samples.
- XRD PANalytical Empyrean: Assessing the crystallinity or otherwise (aromaticity or amorphousness) of biomass samples.
- NETZSCH High Temperature TGA: Batch pyrolysis or thermal analysis of sorbents and microalgae
Biochemical processes can be used for both, CO2 conversion and hydrogen generation, as well as some other environmental applications. Current research interests of projects carried out at the RICH center are the understanding of the selective and environmental forces driving microbial communities’ behavior for process and environmental applications. Processes include anaerobic digestion and fermentation, microbial electrochemical technologies and biological wastewater treatment and resource recovery in general.
Notable equipment used in this lab are:
- Bioreactor Fermac 360 (4 units): fully instrumented fermentation system with reactor vessel, pumping and built-in control systems for pH, temperature and flow. It can be used for a variety of bioreactor setups including anerobic/aerobic cultivations and the ability to work as a photobioreactor when using the light shroud.
- Multichannel potentiostat (BioLogic VMP3): ±10 V adjustable; 400 mA to 10 µA; 1 MHz down to 10 µHz; up to 16 channels.
- Oven/Incubator: up to 250 °C.
- Centrifuge (Hettich Universal 320): Max. Capacity 4 x 200 mL / 6 x 94 mL; Max. RPM/RCF 15,000/21,382.
- Automatic Methane Potential Test System (AMPTS)
- Laminar flow cabinet.
- Biosafety cabinet.
- HACH portable spectrophotometer DR2800: for rapid liquid analysis by using one of the 240 analytical methods available (e.g. total organic carbon, ammonium, nitrate, nitrite, and more).
- HACH HT200S high temperature thermostat: for analysis of COD, TNb, Ptot and heavy metals.
- Shimadzu gas chromatograph with FID detector (shared with Photocatalytic and Chemical Reaction Lab).
- Shimadzu gas chromatograph with TCD detector (shared with Photocatalytic and Chemical Reaction Lab).
- Thermo Scientific HPLC with diode array and refractive index detector (shared with Photocatalytic and Chemical Reaction Lab).
Reducing the CO2 trace of combustion technologies is a crucial component of a sustainable energy portfolio. In order to explore the scientific fundamentals that underlie such technologies, researchers in the Combustion Laboratory in KU address a series of technologies such as biofuel utilization, electrostatically manipulated atomization and combustion, and “solar” fuels. Recently, and within the hydrogen theme in RICH, a strong focus has developed on carbon-less fuels such as ammonia and its mixtures with hydrogen and hydrogen peroxide. The research methodology comprises experiments in idealized burners that are interfaced with optical and laser diagnostics and are used in tandem with high-fidelity computations in order to explore flame aerodynamics, emissions, and ignition dynamics. A recent collaboration with local industrial partners aspires to make a connection between scientific fundamentals and practical combustion devices by installing the first high-pressure combustion testing facility in the UAE. The major pieces of equipment in the laboratory include:
- Atmospheric, water-cooled, counterflow burner for non-premixed flames
- Electrostatically manipulated atomizers and burners
- High-voltage AC/DC generator for versatile AC manipulation (TREK, USA)
- Double-pulsed, 10-Hz, Nd-YAG laser with PIV capability (Spectra Physics, USA)
- 4W CW Ar-Ion laser (Newport, USA)
- Intensified CCD camera (Andor, UK)
- 2000 fps high-speed camera (Photoron FASTCAM, USA)
Fig. 5. Counterflow burner with laser diagnostics in the Combustion Lab at RICH.
During the past decade, atomistic and molecular simulations have become an integral part of materials design and processes, filling the gap to use multiscale modeling from the inception to the final design of processes for ad-hoc applications. This is due to the existence of more accurate first principles methods, free from empirical parameters and applicable to all chemical species, as well as the increased capacity of supercomputers in terms of speed and storage. Recently, the machine-learning (ML) methodology has come as a new player in the field, gaining traction as a data-driven tool to develop accurate models to help in the design of ad-hoc materials.
The RICH center has expertise on the development and application of different modeling tools from Quantum Mechanics and Molecular Simulations to process modeling, optimization and integration, including techno-economic analysis. Expertise also includes machine learning techniques (such as artificial neural networks and others). These methods are used in a complementary manner with the experimental techniques, guiding the optimization of the novel materials CO2 capture, CO2 reduction and H2 production and storage as per defined key properties and performance, as well as other clean energy and sustainable processes. RICH has a dedicated Computational Modeling Lab to carry out this work.
Fig 6. Showcase of the integrated approach used in RICH for process design and optimization by combining experiments with simulations: date seeds-derived activated carbons for CO2 capture
Notable equipment and software used in this lab includes:
- 30 high-end computing workstations
- In-house developed software: work bench soft-SAFT, MOCASIN
- Computational modeling licenses: Materials Studio, VASP, Gaussian
- Process modeling software: gPROMS, Aspen Plus
- Open source modeling software: LAMMPS, RASPA, Quantum Espresso
Additionally, the Research Computing Department of Khalifa University provides hardware and software resources as well as technical support and training to carry out the simulations. The Department owns a large HPC cluster with state of the art processors; additional cloud computing time is available.