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Catalytic amination of isopropanolamine and ammonia to 1,2-propanediamine over Raney Ni with potassium carbonate as the additive was reported. Characterization of N2 adsorption–desorption and XRD were performed to reveal the textural and structural properties of the catalysts. With the additive of potassium carbonate, the selectivity of 1,2-propanediamine was improved, while the side generation of 2,5-dimethylpiperazine was suppressed. The catalytic reaction parameters were optimized and the yield of 1,2-propanediamine reached 80% under the optimized reaction condition.

Cobalt-nitrogen-doped carbon nanotubes stably supported on diatomite were obtained by employing Co(OAc)2/phenanthroline. The resulting material was found to be excellent catalysts for the carbonylation of a variety of amines with CO other than phosgene. Both high activity and selectivity were achieved in this carbonylation process, and it allows air as a cheap oxidizing agent. Moreover the catalyst could be recycled for several times with relatively higher activity compared to homogeneous catalyst palladium acetate.

As a nano-adsorbent, magnetic graphene oxide (GO/Fe3O4) was synthesized to potentially adsorb propranolol (PRO) from water. The synthetic material was characterized by SEM, TEM, VSM, FTIR, XRD, zeta potential, and XPS. The environmental factors, such as pH, humic acid concentration, PRO concentration, and contact time, were investigated regarding their effect on the adsorption process. The kinetics data fitted the pseudo first-order and second-order kinetics equations. The Langmuir equation, the Freundlich equation, and the Sips equation were used to analyze the adsorption isotherms. Electrostatic attraction, hydrogen bonding, and the &pi, &ndash, &pi, interaction all contributed to the adsorption process of PRO onto GO/Fe3O4. The discovery of this study emphasized the feasibility of GO/Fe3O4 removal of PRO and expanded the scope of the application of GO.

In this work, a novel adsorbent attapulgite/graphene oxide magnetic composite (ATP/Fe3O4/GO) was synthesized for removing propranolol (PRO) from aqueous water. The factors affecting the PRO adsorption process onto ATP/Fe3O4/GO including pH, ionic strength, sorbent dosage, and humic acid were systematically investigated by batch experiments. Meanwhile, magnetic attapulgite (ATP/Fe3O4) and magnetic graphene oxide (GO/Fe3O4) were prepared for the comparison of the adsorption performance for PRO. The structural and surface characteristics of the resulting materials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, zeta potential measurements, and scanning electron microscope. The results showed that the adsorption rate of PRO onto ATP/Fe3O4/GO was up to 99%, faster and higher than that of other adsorbents involved at neutral pH. Moreover, the adsorption kinetics were better fitted with pseudo-first-order kinetic model than the second-order kinetic model. The adsorption data were fitted well with the Freundlich isotherm equations, implying that the adsorption process was heterogeneous. The adsorption reaction was endothermic and spontaneous according to the thermodynamic parameters. All results indicated that ATP/Fe3O4/GO was a promising adsorbent for removing PRO from water.

This study explored the feasibility of utilizing a novel sorbent humic acid (HA) coated Fe3O4/attapulgite (MATP) magnetic nanoparticles (HMATP) for the sorption of propranolol from aqueous solutions. MATP and bare Fe3O4 nanoparticles were also synthesized under similar preparation conditions. The FTIR, Zeta potential, XRD, VSM, TEM, and TGA analyses were conducted to characterize the sorbent materials. The effects of pH, sorbent dosage, ionic strength, HA in the aqueous solution, contact time and initial sorbate concentration on sorption of propranolol were investigated using batch sorption experiments. The results suggested that the sorption capacity of HMATP showed little change from pH 4 to 10. Na+ and Ca2+ slightly inhibited the sorption of propranolol on HMATP. While HA in solution enhanced both MATP and HMATP, which indicated that HMATP can resist HA interference in water. Further, the less leaching amounts of Fe and HA suggested a good stability of HMATP. In all conditions, sorption capacity of propranolol on HMATP was obviously higher than that on MATP, which indicated that surface-coated HA played an important role in the propranolol sorption process. Electrostatic interaction, cation exchange, hydrogen bonding, and &pi, &ndash, &pi, electron donor acceptor interactions were considered as the sorption mechanisms.

Application of extraction and adsorption process to the alkylpyrazine removal from wastewater was investigated. The detailed extraction process was studied. It was found that the alkylpyrazine content in the water phase after extraction was decreased to 0.3% or less from about 3.0% (wt.). Extractant was recovered by concentrating the water phase and then the wastewater generated from concentration process was disposed by adsorption treatment in order to further lower the level of alkylpyrazine in wastewater. Adsorption of simulated wastewater containing 2,3-dimethylpyrazine on the different resins was also investigated. Among the resins of various grades used, the XDA-200 had the best properties in decontamination of aqueous 2,3-dimethylpyrazine solutions. The chemical oxygen demand (COD) of authentic wastewater generated from extraction process after adsorption treatment with XDA-200 was less than 1,000 mg/L and its removal percentage was above 90%. It was shown that regeneration of the adsorbent...