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Magnetic particles (MPs) assisted powdered activated carbon (PAC) is a promising composite material for adsorption removal of micropollutants. The fractional amount of Fe 3 O 4 impacts the balance between adsorption capacity and magnetic property of magnetic activated carbons (MPACs), and therefore it affects the extent of sulfamethoxazole (SMX) removal. Here, five MPACs with different mass ratios of Fe 3 O 4 : PAC (1:1, 1:2, 1:4, 1:6, and 1:8) were prepared using a hydrothermal method and characterized by various spectroscopic methods. The spherical shaped MPs were monolayerly deposited on PAC with fewer pores blocked when the mass ratio of Fe 3 O 4 was comparatively low (≤ 20%). MPAC6 (14.3 wt% of Fe 3 O 4 ) had the best overall performance, with good Langmuir adsorption capacities for SMX (173.0 mg g -1 ) and excellent magnetic properties (9.0 emu g -1 ). Corresponding adsorption kinetics fitted well with the pseudo second-order kinetic model. The negative ΔG 0 (-25.6 to -27.2 KJ mol -1 ) and ΔH 0 (-9.14 KJ mol -1 ), and positive ΔS 0 (0.55 KJ mol -1  K -1 ) properties indicated the spontaneous and exothermic nature of the adsorption process accompanied by an increase in entropy. The strong cation-assisted electron donor-acceptor and hydrophobic interactions were contributed to a high extent of SMX removal in the pH range of 2-4. Formation of negative charge-assisted H-bonds was responsible for the adsorption of hydrophilic SMX - on negatively charged MPAC6 in alkaline solution. Desorption and regeneration experiments showed SMX removal was still 92.3% in the 5th cycle. These findings give valuable insights into the interactions between SMX and MPACs and guide for choosing sustainable magnetic adsorbents for environmental applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

An efficient Sb-doped SnO 2 electrode featuring superior electrocatalytic characteristic and long stability was constructed by adopting clustered TiO 2 nanotubes-covered Ti mesh as substrate (M-TNTs-SnO 2 ). Compared with the electrodes prepared with mere Ti mesh or Ti plate grew with TiO 2 nanotube, the M-TNTs-SnO 2 exhibited higher TOC removal (99.97 %) and mineralization current efficiency (44.0 %), and longer accelerated service lifetime of 105 h for electrochemical degradation of phenol. The enhanced performance was mainly ascribed to the introduction of mutually self-supported TiO 2 nanotube clusters in different orientations. Such unique structure not only favored a compact and smooth surface of catalyst layer which improved the stability of electrode by reinforcing the binding force between substrate and catalyst layer, but also increased the loading capacity for catalysts, leading to 1.5-2.2 times higher of ·OH generation, the main active species for indirect electrochemical oxidation of phenol. Meanwhile, the transverse electron transfer from TiO 2 nanotube to catalyst layer was possibly achieved to further prompt the generation of ·OH. This study may provide a feasible option to design of efficient electrodes for electrocatalytic degradation of organic pollutants., (Copyright © 2020. Published by Elsevier B.V.)