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• Surfactants were used in a dedusting technology combing heterogeneous condensation and cyclone. • Better condensable growth and removal effect for fine particles was obtained. • The MD simulation was used to explore the improvement mechanism of surfactants. • The solid–liquid interaction energy was reduced and mobility of water molecules was improved. • The spatial distribution of the head group and tail chain is an important influence factor. Using heterogeneous-condensation agglomeration to enhance removal of fine particles by conventional equipment is an economical and efficient method. Recently proposed Cloud-Air-Purifying (CAP) technology, which combines heterogeneous-condensation agglomeration with a centrifugal field, has significantly improved the removal efficiency of fine particles in gas cyclones. In this work, surfactants were used to further enhance the removal of fine particles. The effect of three surfactants on promoting the removal of fine particles was investigated experimentally. The results indicated that non-ionic surfactant octylphenol polyoxyethylene ether (10) (OP-10) had the best effect on promoting the removal of methylated silica (SiO 2 -CH 3) particles, because it improved heterogeneous condensation of fine particles and collision agglomeration between particles by improving the surface wettability, resulting in the formation of larger aggregates. Furthermore, the interaction energy, mean square displacement and hydrogen bond interactions in different simulation systems were calculated by molecular dynamics simulation to study the mechanism of surfactants on improving the surface wettability. The simulation results demonstrated the hydrophobic tail chains of OP-10 molecules spontaneously adsorbed on the nonpolar SiO 2 (0 0 1)–CH 3 surface through the Van der Waals interaction, which changed the surface polarity and reduced the solid–liquid interaction energy. Meanwhile, hydrogen bonds were formed between polar head groups and water molecules, which enhanced the interaction between water molecules and the surface. Moreover, the mobility of water molecules is enhanced by surfactant molecules. The spatial distribution of the head group and tail chain of surfactant is an important factor affecting the surface wettability. This work is of great importance for enhancing the removal of fine particles in the dedusting system with heterogeneous-condensation agglomeration technology. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of Tb-Fe-O nanocomposites via rapid microwave technique. • Investigation of diverse synthesis circumstances on dimension properties of nanostructures. • Consideration of electrochemical hydrogen storage capacity of obtained nanostructures. • Discharge efficiency of 490 mAh g−1 after 15 cycles for TbFeO 3 /Tb 3 Fe 5 O 12 nanocomposites. Nano-sized Tb-Fe-O (TFO) structures were fabricated via rapid microwave route using Tb(NO 3) 3 ·6H 2 O and Fe(NO 3) 3 ·9H 2 O precursors and verjuice (lemon juice) complexing agent as a surfactant. Verjuice complexing agent including collection of carboxylic acids control nucleation and growth of formed crystals with creation of spatial barrier around the cations, and finally prevent nano-product agglomeration. Changing of parameters in synthesis reaction consisting of surfactant, microwave power and solvent in turn offers a virtuous control over the nanocomposites size and shape which various compositions of pure TbFeO 3 nanoparticles, Tb 3 Fe 5 O 12 /TbFeO 3 and TbFeO 3 /Tb 3 Fe 5 O 12 nanocomposites obtained. The as-prepared Tb-Fe-O nano-products were characterized thorough scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), UV–Vis, BET and energy dispersive X-ray (EDX) analyses in terms of crystallinity structure, composition, porosity and morphology. Different forms of Tb-Fe-O nanostructures were evaluated for electrochemical hydrogen storage capacity through chronopotentiometry technique in stable current (1 mA). The achieved Tb-Fe-O nanoparticles could be applied as a favorable candidate active material for electrochemical hydrogen storage. Optical, magnetic and reducible characteristics of Tb-Fe-O nanostructures have positive effect on electrochemical hydrogen storage capacity. It was found out that the TbFeO 3 /Tb 3 Fe 5 O 12 nanocomposites have the best electrochemical hydrogen storage performance due to oxidation–reduction process of Fe2+/Fe3+ components which can help to charging-discharging process of hydrogen to increase the storage capability to 490 mAh g−1 after 15 cycles. [ABSTRACT FROM AUTHOR]