Rana Sabouni

Carbon dioxide capturing technologies: a review focusing on metal organic framework materials (MOFs)

In this study, a relevant literature has been reviewed focusing on the carbon dioxide capture technologies in general, such as amine-based absorption as conventional carbon dioxide capturing technology, aqueous ammonia-based absorption, membranes, and adsorption material (e.g., zeolites, and activated carbons). In more details, metal organic frameworks (MOFs) as new emerging technologies for carbon dioxide adsorption are discussed. The MOFs section is intended to provide a comprehensive overview of MOFs including material characteristics and synthesis, structural features, CO2 adsorption capacity, heat of adsorption and selectivity of CO2.

Mathematical modeling and experimental breakthrough curves of carbon dioxide adsorption on metal organic framework CPM-5.

It is essential to capture carbon dioxide from flue gas because it is considered one of the main causes of global warming. Several materials and different methods have been reported for CO2 capturing including adsorption onto zeolites and porous membranes, as well as absorption in amine solutions. All such methods require high energy input and high cost. A new class of porous materials called Metal Organic Frameworks (MOFs) exhibited excellent performance in extracting carbon dioxide from a gas mixture. In this study, the breakthrough curves for the adsorption of carbon dioxide on CPM-5 (crystalline porous materials) were obtained experimentally and theoretically using a laboratory-scale fixed-bed column at different experimental conditions such as feed flow rate, adsorption temperature, and feed concentration. It was found that the CPM-5 has a dynamic CO2 adsorption capacity of 11.9 wt % (2.7 mmol/g) (corresponding to 8 mL/min, 298 K, and 25% v/v CO2). The tested CPM-5 showed an outstanding adsorption equilibrium capacity (e.g., 2.3 mmol/g (10.2 wt %) at 298 K) compared to other adsorbents, which can be considered as an attractive adsorbent for separation of CO2 from flue gas.

Anti-cancer Drug Delivery Using Metal Organic Frameworks (MOFs)

Cancer is the uncontrolled growth of cells in the body and is considered as one of the major causes of death globally. There are several cytotoxic chemotherapeutic agents used to treat cancer including methotrexate, 5-fluorouracil, cisplatin, tamoxifen, doxorubicin and others. Although billions of dollars have been spent on cancer research to develop these chemotherapies, it still remains a major illness for mankind partly due to the shortcomings of these therapies. These shortcomings include low targeting specificity, severe side effects (due to high doses) and poor pharmacokinetics. To avoid these drawbacks, anti-cancer drug delivery systems have been developed recently using nanocarriers including liposomes, micelles, polyelectrolyte capsules and others. One of the recent class of nanoparticles investigated for chemotherapeutic use are metal organic frameworks (MOFs) which are hybrid polymers that consist of metal ions or clusters and organic ligands. MOFs are used in many applications including gas/vapor separation, gas storage, catalysis, luminescent materials, and biomedical imaging. These structures have additional features that promote their use as drug carriers in the biomedical field. First, they are nontoxic, biodegradable and have the ability to carry high loadings of the anti-neoplastic agent due to their porous nature. Also, they have well-defined crystalline structures that can be characterized by different analytical techniques and their sizes are suitable to control their in vivo drug release. This paper reviews the methods used to synthesize MOFs and their recent use as antineoplastic drug delivery carriers.

Emulsification Characteristics Using a Dynamic Woven Metal Microscreen Membrane

An oscillatory emulsification system for the production of oil in water emulsions using a commercially available low-cost woven metal microscreen (WMMS) is investigated. The system allows for independent control of both the oscillation frequencies and amplitudes such that it provides two degrees of freedom for controlling the emulsion properties. The investigations included the production of both surfactant and particle-stabilized emulsions. The average droplet size was found to decrease when both the oscillation frequency and amplitude was increased. For surfactant-stabilized emulsions, using bi-surfactants in both the continuous and dispersed phases resulted in a smaller droplet size due to lower interfacial tension. For particle-stabilized emulsions, both the hydrodynamics of the system and the hydrophobic and hydrophilic nature of the stabilizing particles influenced the interfacial properties at the oil–water interface, which in turn affected the final droplet size and distribution with potential droplet breakage. In absence of the latter, a simple torque balance model can be used to reasonably predict the average emulsion droplet size.