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Catechol, a structure widely found in nature with a strong interaction with iron (Fe) ions, was used as a monomer to prepare a hypercrosslinked polymer (HCP) as a solid adsorbent for Fe removal from water. The catechol-based HCP (Catechol-HCP) was synthesized via Friedel–Crafts alkylation and characterized by FT-IR spectroscopy, elemental analysis, and BET surface area analysis. The HCPs based on toluene, phenol, and hydroquinone monomers were also prepared to compare their Fe adsorption efficiency. Comparing to toluene-, phenol-, and hydroquinone-based HCPs, Catechol-HCP showed a significantly higher Fe adsorption indicating the important of the strong interaction of catechol unit to the Fe ion. Factors including adsorbent dose, contact time, initial solution concentration, and temperature were studied on their effects on the adsorption efficiency. The Catechol-HCP could remove Fe from water more than 40 mg g−1 or 94%. The adsorption isotherm was fitted to the Langmuir model with the RL value between 0 and 1 indicating the favorable adsorption. The kinetics study suggested the adsorption occurred as a pseudo-second-order mechanism. Moreover, the material showed a good reusability demonstrating the cost effectiveness of the material which would be beneficial for further practical utilizations. [ABSTRACT FROM AUTHOR]

A hypercrosslinked polymer (HCP)-immobilized ruthenium catalyst (HCP-PPh3-Ru) was prepared from benzene and triphenylphosphine (PPh3) through a one-step external cross-linking reaction. The structure and composition of the catalyst were fully characterized by many physicochemical methods. HCP-PPh3-Ru was found to possess high Brunauer-Emmett-Teller (BET) surface area, large pore volume, and low skeletal density. Moreover, the Ru catalyst was also featured some advantages, such as low synthetic cost and good chemical and thermal stability. HCP-PPh3-Ru was then used as a recoverable and effective catalyst for the synthesis of 2,4-diaryl-substituted pyridines from acetophenones, ammonium acetate (NH4OAc) and dimethylformamide (DMF), and the cycloaddition reaction of diazodicarbonyl compounds with olefins to afford dihydrofurans. In addition, a combination of HCP-PPh3-Ru and Amberlyst-15 enabled us to establish a simple protocol for the direct synthesis of carbazole derivatives from diazodicarbonyl compound, alkyl vinyl ether and indole. In these selected reactions, the catalyst was easily recovered and reused several times without significant activity loss. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) is one of the best candidates to replace current petroleum energy resources due to its rich abundance and clean combustion. However, the storage of H2 presents a major challenge. There are two methods for storing H2 fuel, chemical and physical, both of which have some advantages and disadvantages. In physical storage, highly porous organic polymers are of particular interest, since they are low cost, easy to scale up, metal-free, and environmentally friendly. In this review, highly porous polymers for H2 fuel storage are examined from five perspectives: (a) brief comparison of H2 storage in highly porous polymers and other storage media; (b) theoretical considerations of the physical storage of H2 molecules in porous polymers; (c) H2 storage in different classes of highly porous organic polymers; (d) characterization of microporosity in these polymers; and (e) future developments for highly porous organic polymers for H2 fuel storage. These topics will provide an introductory overview of highly porous organic polymers in H2 fuel storage. [ABSTRACT FROM AUTHOR]