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In this study, we investigated the effect of Ni/SiO2 hollow spheres (HS) particle size on the activity for 4-nitrophenol (4-NP) reduction. The SiO2 HS, which serves as Ni support was synthesised by sol-gel method using polystyrene (PS) particles with various diameters. TEM images show that the diameters of the SiO2 HS were 330, 445, and 490 nm. To prepare the Ni/SiO2 HS, Ni particles were immobilised by the impregnation method. SEM images of the Ni/SiO2 HS with a diameter of 330 nm show uniform spherical particles. The Ni were confirmed the surface of SiO2 HS using the EDX. Meanwhile, small particles with irregular shapes were observed in the Ni/SiO2 HS with diameters of 445 and 490 nm. The reaction for 4-nitrophenol reduction was evaluated using the obtained samples. We found that the sample with a diameter of 330 nm shows high activity. Additionally, we reveal that the SiO2 HS enhances the activity by adsorbing the 4-NP. [ABSTRACT FROM AUTHOR]

In this study, we investigated the preparation conditions of polystyrene (PS)@TiO2 core–shell particles and their photocatalytic activity during the decomposition of methylene blue (MB). TiO2 shells were formed on the surfaces of PS particles using the sol–gel method. Homogeneous PS@TiO2 core–shell particles were obtained using an aqueous NH3 solution as the promoter of the sol–gel reaction and stirred at room temperature. This investigation revealed that the temperature and amount of the sol–gel reaction promoter influenced the morphology of the PS@TiO2 core–shell particles. The TiO2 shell thickness of the PS@TiO2 core–shell particles was approximately 5 nm, as observed using transmission electron microscopy. Additionally, Ti elements were detected on the surfaces of the PS@TiO2 core–shell particles using energy-dispersive X-ray spectroscopy analysis. The PS@TiO2 core–shell particles were used in MB decomposition to evaluate their photocatalytic activities. For comparison, we utilized commercial P25 and TiO2 particles prepared using the sol–gel method. The results showed that the PS@TiO2 core–shell particles exhibited higher activity than that of the compared samples. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, the adsorptive ability of the konjac glucomannan gel containing activated carbon (KGMG-AC) was investigated by measuring the removal of several organic compounds with different charges, such as nitrobenzene (NB), methylene blue (MB), and rose bengale (RB). The physical and chemical properties, adsorption dynamics, adsorption isotherms, and the effect of pH of the adsorbents were compared with those of a commercially available powdered activated carbon (AC). The results of the present study indicate that the removal ratio of NB, MB, and RB onto KGMG-AC was slightly higher than that of the AC. The adsorption equilibrium constant ( KL) value (0.02 L/mg) of KGMG-AC for NB was similar to that of AC (0.03 L/mg). However, the saturated adsorption amount ( Q0) of KGMG-AC (368 mg/g) for NB was slightly larger than that of AC (354 mg/g). The saturated adsorption amounts of MB and RB on KGMG-AC were 302 and 259 mg/g, respectively. On the other hand, a high molecular weight humic acid was not adsorbed by KGMG-AC. Thus, entrapping AC into KGMG resulted in the selective adsorption. Therefore, this study could show that KGMG-AC was a new environmental friendly adsorbent that can be easily prepared, used, and recovered in environments. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40542. [ABSTRACT FROM AUTHOR]