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A novel reactant permeation template method was used for the first time to synthesize centimeter-scale aligned porous carbon microtubes, which showed highly efficient selective adsorption and seperation capacity for methylene blue from other dyes. [Display omitted] • Aligned porous carbon microtubes of macroscopic size were prepared for the first time. • A novel reactant permeation template method was used to prepare the carbon microtubes. • The carbon microtubes could adsorb and separate MB selectively from other dyes. • Both the adsorbed MB and the carbon microtubes could be recycled by desorption. • The selective adsorption mechanism of the carbon microtubes was fully researched. Selective adsorption was beneficial to the separation and recovery of valuable dyes and highly efficient resource utilization. Modified aligned porous carbon microtubes (MAPCTs) in centimeter scale were prepared by a novel reactant permeation template method without addition of pore former. In a solution of pH 8, MAPCTs showed excellent adsorption capacity for cationic dye methylene blue (MB), which reached 1875.4 mg/g when the initial concentration of MB increased to 200 mg/L. The adsorption process was fitted by isotherm model and kinetic model. In addition, MAPCTs could selectively separate MB from cationic dye rhodamine B (RhB) or anionic dye methyl orange (MO) mixture solutions, because the reactant permeation template method well controlled the characteristics of the pores. The separation efficiency for MB/RhB and MB/MO solutions was 99.7 %. The adsorbed MB could be efficiently regenerated from the recycled MAPCTs and the adsorption–desorption could be repeated for at least 5 times, keeping the regeneration efficiency 98 %. The selective adsorption and separation process could follow a diffusion limitation and size exclusion mechanism and an electrostatic repulsion mechanism. Since the reactant permeation template method can be easily used for industrial mass production of MAPCTs, this method and MAPCTs have great potential for recycling MB from industrial wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Form MCM-41/PDMS hybrid membrane on tubular ceramic substrates for the first time. • Develop novel approach of enriching aromatic compound from aqueous tobacco extract. • Impact of the nanofiller loading to the pervaporation of different components. • Evaluate the impact of ethanol as an additive to hydrophobic pervaporation. • Achieve high fluxes in processing actual aqueous tobacco extract at mild condition. Recovery of valuable aromatic compounds from tobacco waste is important, and efficient separation methods remain highly demanding. This work proposed a hybrid PDMS membrane for high flux aromatic compounds recovery. MCM-41, a silicone-based molecular sieve, was selected to fabricate the membrane to improve the pervaporation performance. The prepared MCM-41/PDMS membrane was investigated in model aqueous solution at different concentrations and temperatures. The optimal pervaporation fluxes of the MCM-41/PDMS membrane achieved 0.95 g/(m2·h), 0.51 g/(m2·h), and 0.26 g/(m2·h) for 2-phenylethanol, β-ionone, and dihydroactinidiolide, respectively, exhibiting superior performance to the PDMS membrane. Moreover, the long-term stability of the hybrid membrane was examined with practical tobacco extract. The average fluxes were 41.20 mg/(m2·h), 20.57 mg/(m2·h), and 9.73 mg/(m2·h), respectively. The hybrid PDMS membrane in this study, with high permeate flux and selectivity, is promising for recovery of aromatic compounds particularly from tobacco waste. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we prepared carbon nanotube (CNT) electrodes with polytetrafluoroethylene (PTFE) as binders to adsorb NaCl from water. The electrodes were characterized using scanning electron micrograph (SEM), nitrogen adsorption and cyclic voltammetry. The adsorption/electrosorption rate and capacity of CNT electrodes with different bias potentials were measured, and the electrosorption isotherms and kinetics were also investigated. The results showed that electrosorption can effectively increase the adsorption capacity and rate of NaCl on CNT electrodes. The adsorption/electrosorption of NaCl on CNT electrodes followed Langmuir isotherms and the pseudo-first-order adsorption kinetics. The equilibrium adsorption capacity at 1.2V was 9.35mg/g, which was nearly eight times higher than that at 0V. Compared with the adsorption rate at 0V, the adsorption rate at 1.2V was increased by 58.9%. The enhancement of capacity and rate may be due to the forming an electric double layer on the surface of CNT electrodes in the solution. [Copyright &y& Elsevier]

Highlights: [•] We develop a novel process for erythromycin A separation from fermentation broth. [•] Pore diffusion limits the rate of fixed-bed adsorption of erythromycin onto resins. [•] Erythromycin recovery efficiency from filtrated broth into butyl acetate is over 96%. [•] Selectivity of Erythromycin A over Erythromycin C is 2.2 in aqueous crystallization. [Copyright &y& Elsevier]