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The indoor air quality is of prime importance for human daily life and health, for which the adsorbents like zeolites and silica‐gels are widely used for air dehumidification and harmful gases capture. Herein, we develop a pore‐nanospace post‐engineering strategy to optimize the hydrophilicity, water‐uptake capacity and air‐purifying ability of metal‐organic frameworks (MOFs) with long‐term stability, offering an ideal candidate with autonomous multi‐functionality of moisture control and pollutants sequestration. Through variant tuning of organic‐linkers carrying hydrophobic and hydrophilic groups in the pore‐nanospaces of prototypical UiO‐67, a moderately hydrophilic MOF (UiO‐67‐4Me‐NH2‐38 %) with high thermal, hydrolytic and acid‐base stability is screened out, featuring S‐shaped water sorption isotherms exactly located in the recommended comfortable and healthy ranges of relative humidity for indoor ventilation (45 %–65 % RH) and adverse health effects minimization (40–60 % RH). Its exceptional attributes of water‐uptake working capacity/efficiency, contaminants removal, recyclability and regeneration promise a great potential in confined indoor environment application. [ABSTRACT FROM AUTHOR]

The indoor air quality is of prime importance for human daily life and health, for which the adsorbents like zeolites and silica‐gels are widely used for air dehumidification and harmful gases capture. Herein, we develop a pore‐nanospace post‐engineering strategy to optimize the hydrophilicity, water‐uptake capacity and air‐purifying ability of metal‐organic frameworks (MOFs) with long‐term stability, offering an ideal candidate with autonomous multi‐functionality of moisture control and pollutants sequestration. Through variant tuning of organic‐linkers carrying hydrophobic and hydrophilic groups in the pore‐nanospaces of prototypical UiO‐67, a moderately hydrophilic MOF (UiO‐67‐4Me‐NH2‐38 %) with high thermal, hydrolytic and acid‐base stability is screened out, featuring S‐shaped water sorption isotherms exactly located in the recommended comfortable and healthy ranges of relative humidity for indoor ventilation (45 %–65 % RH) and adverse health effects minimization (40–60 % RH). Its exceptional attributes of water‐uptake working capacity/efficiency, contaminants removal, recyclability and regeneration promise a great potential in confined indoor environment application. [ABSTRACT FROM AUTHOR]

The oxytetracycline bacterial residue–activated carbon (OBR-AC) prepared from oxytetracycline bacterial residue with K2CO3 under chemical activation was studied. The effects of activation temperature, activation time, and activation ratio on the specific surface area (SSA) and methylene blue adsorption (MBA) were studied. Characterization of the optimum OBR-AC was performed by using scanning electron microscopy (SEM), pore structure (PS,) and Fourier-transform infrared spectroscopy (FT-IR). The optimum parameters were as follows: 800°C activation temperature, 3 hr activation time, and 1:3 activation ratio. The SSA and MBA under optimum conditions were 1593.09 m2/g and 117.0 mg/g, respectively. Adsorption equilibrium and kinetics data were determined for the adsorption of phenol from the synthetically prepared phenol solution. The results showed that the Langmuir model gave the best fit for equilibrium isotherm, whereas the kinetics data were well fitted by the pseudo-second order model. [ABSTRACT FROM AUTHOR]

Abstract: Rice straw as a lignocellulosic agricultural residue was chemically converted into a strong basic anion exchanger (RS-AE). Epoxy and amino groups were introduced into raw rice straw by reaction with epichlorohydrin and trimethylamine after it was treated in sodium hydroxide solution. The exchangers were characterized by element analysis, Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). The results showed that total exchanger capacity of rice straw was increased by 1.32mEq/g, and quaternary amino groups were formed on its new fibrous surface after modification. Batch adsorption experiments suggested RS-AE exhibits a much higher sulphate maximum adsorption capacity (74.76mg/g) in contrast to that of raw straw (11.68mg/g). The equilibrium data were described by Langmuir and Freundlich isotherm models, respectively, and were found to agree very well with the former. RS-AE also showed a good performance in regeneration cycles and a high selectivity for sulphate ions. [Copyright &y& Elsevier]