| Due to the large specific surface area, tunable pore size, outstanding adsorption capacity, acid-alkali resistance, chemical and thermal stability, ordered mesoporous carbons have been widely used in gas purification, water treatment, catalyst supports, sensors, electrode materials, drug delivery and many other fields.Firstly, Ordered mesoporous carbon with hexagonal arrays of tubular-type pores (CMK-5) was synthesized via a nanocasting process by directly using SBA-15 as a template, furfuryl alcohol as a carbon source and oxalic acid as the catalyst. The structure of CMK-5 was analyzed by a series of different techniques, including the scanning and transmission electron microscopy, powder X-ray diffraction, and N2 adsorption analysis. The as-synthesized CMK-5 exhibits a tubular structure with double pore system. The specific surface area and pore volume are 1856m2/g and 2.10 cm3/g, respectively, with mesopore sizes concentrated at 3.1 and 5.5 nm.Secondly, CMK-5 was investigated for the adsorption of the industrial dyes reactive blue 19, acid red 57 and fuchsin basic in aqueous solutions at room temperature. It was found that CMK-5 exhibits an ultrahigh adsorption rate and superior adsorption capacities for these dyes. Its maximum adsorption capacities for reactive blue 19, acid red 57 and fuchsin basic were 733, 1131 and 1403 mg/g. The Langmuir, Freundlich and Redlich-Peterson isotherm models were employed to describe the adsorption of these three dyes. The adsorption is closer to the Langmuir model for reactive blue 19 and fuchsin basic, and the Redlich-Peterson model gives a better fit for the isotherm of acid red 57.For comparison, ordered mesoporous carbon CMK-3, polymer based disordered mesoporous carbon, and steam and CO2 activated commercial coconut carbons were investigated for the adsorption of reactive blue 19. The adsorption quantities on carbons are in the order of CMK-5>CMK-3>ACC-1>ACC-2>RFMC. The recyclability of a dye adsorbent via thermal annealing was investigated for the adsorption of reactive blue 19. The adsorption capacity of CMK-5-2nd is 447 mg/g, which is approximately 77% of the original capacity. After 2 cycles, CMK-5-3rd still performs well with the adsorption capacity of 421 mg/g in removal of reactive blue19, which is approximately 72% of the original capacity.Lastly, the adsorption behavior of CMK-5 towards vitamin B12 was investigated in aqueous solutions at room temperature. The adsorption capacities can be high up to 1088 mg/g in a short period of 120 min, which is significantly greater than that of commercial activated carbon. The fast adsorption rate of CMK-5 carbon is due to its unique properties of tubular mesostructure, bimodal mesopore system and high surface area. Langmuir model gives a better fit for the isotherm of vitamin B12. The vitamin B12 release was also investigated under intervel and continuous condition, respectively. The composite of CMK-5 and vitamine B12 without any treatment, such as pH response or thermal response, has slow-release performance in a simulated body fluid. The concentration of release solutions remained 9 mg/L under continuous condition. A high loading capacity and slow release rate of vitamin B12 on the support CMK-5 suggested that CMK-5 with unique bimodal pores have great potential applications in drug delivery field.
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