Porous polybenzimidazole polymers have been under investigation for high and low pressure CO2 adsorption due to the well-built stability under high pressure and at various temperatures. Pressure swing and temperature swing processes like integrated gasification combined cycle require materials which can operate efficiently at high pressure and high temperature and can remove CO2. In this manuscript we report synthesis, characterization and evaluation of two polybenzimidazole materials (PBI-1 and PBI-2), which were prepared with two different solvents and different cross-linking agents by condensation techniques. Low and high pressure CO2 sorption characteristic of both the materials were evaluated at 273 and 298 K. Thermal gravimetric analysis showed high temperature stability up to 500 °C for the studied materials. PBI-1 has shown very good performance by adsorbing 3 times more (1.8025 mmolg−1 of CO2) than PBI-2 at 0 °C and at low pressures. Despite low surface area results obtained via BET techniques, at 50 bars PBI-1 adsorbed up to 6.08 mmolg−1 of CO2. Studied materials have shown flexible behavior under applied pressure that leads to so-called “gate-opening” adsorption behavior and it makes these materials promising adsorbents of CO2 at high pressures and it is discussed in the manuscript in detail.

Nanoscale zero-valent iron (nZVI), with its reductive potentials and wide availability, offers degradative remediation of environmental contaminants. Rapid aggregation and deactivation hinder its application in real-life conditions. Here, we show that by caging nZVI into the micropores of porous networks, in particular Covalent Organic Polymers (COPs), we dramatically improved its stability and adsorption capacity, while still maintaining its reactivity. We probed the nZVI activity by monitoring azo bond reduction and Fenton type degradation of the naphthol blue black azo dye. We found that depending on the wettability of the host COP, the adsorption kinetics and dye degradation capacities changed. The hierarchical porous network of the COP structures enhanced the transport by temporarily holding azo dyes giving enough time and contact for the nZVI to act to break them. nZVI was also found to be more protected from the oxidative conditions since access is gated by the pore openings of COPs.

Beside IGCC, efficient storage and transportation of CO2 and other gases require pressurize conditions. CO2 and other gases adsorption on solid sorbents at high pressure and various temperatures are extremely important as long as the environmental purification via gas capture and separation and gas transpiration are concern. The main objective of the present research was to investigate the effect of amine impregnation on the CO2, methane and nitrogen adsorption capacity of mesoporous silica (SBA-15). Ordered mesoporous silica (SBA-15) was prepared and modified with ammonium hydroxide solution to introduce NH2 functional groups within the pores of materials to produce modified SBA-15 (MSBA-15). The newly prepared materials were characterized with X-ray diffraction analysis, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis were performed to measure pore volume as well as the surface area of both the unmodified and modified samples. Results revealed that the crystal structures of SBA-15 were matched with that of MSBA15; yet, pore volume of the modified material was almost reduced to 50% of the pristine material indicating amine loading into the pore channels. Importantly, gas sorption capacity was investigated at 200bars and three different temperatures of 318K, 328K, and 338K by using state-of-the-art gravimetric Rubotherm® magnetic suspension sorption apparatus. Gas sorption experiments showed that modified mesoporous silica adsorbed 1.6164mmol/g of CO2 at 1bar which is almost double than that of 0.6462mmol/g adsorbed by unmodified material. Quantitative selectivity of both the materials varied as CO2>CH4>N2

A new carbon–carbon bonded nanoporous polymer network was synthesized via efficient and catalyst free Knoevenagel-like condensation polymerization in near quantitative yields. The obtained polymer network, Covalent Organic Polymer – COP-100 possesses strong fluorescent properties and designed solubility in polar aprotic solvents, which shows promise for use as a metal-sensing material in solution. COP-100 exhibited high selectivity towards Fe2+ and Fe3+ in the presence of other common metal cations (Al3+, Ag+, Cd2+, Co2+, Cr3+, Cu2+, Hg2+, Mg2+, Mn2+, Na+, Ni2+, Zn2+) as the fluorescence of the polymer was significantly quenched even at very low concentrations. In the range from 2.5 × 10−6 to 2 × 10−4 M, a linear fluorescence emission response with equipment limited detection minimum of 2.13 × 10−7 M and 2.45 × 10−7 M for Fe2+ and Fe3+, respectively, was observed. These results suggest that COP-100 is a promising material as a selective fluorescence sensor for iron ions.

Same but different: Chemically similar nanoporous azobenzene polymers that are synthesized by using different polymerization routes show completely different gas-sorption characteristics (see figure). Pore widths of 6–8 Å and small particle sizes are very critical for high CO2/N2 selectivity. Furthermore, N2 phobicity is associated with the azo linkages and is realized at warm temperatures.