High-performance removal of methyl mercaptan by nitrogen-rich coconut shell activated carbon

Abstract

A series of nitrogen-doped coconut shell activated carbon catalysts were prepared by urea or melamine impregnation followed by heat treatment and used for the removal of methyl mercaptan (CH 3 SH). The physical and chemical properties of the nitrogen-doped coconut shell activated carbons were evaluated by nitrogen adsorption/desorption, scanning electron microscopy, X-ray photoelectron spectroscopy, elemental analysis, Boehm titration, and thermal analysis. The results show that CH 3 SH capacity depends on the nitrogen content. Further research indicates that pyridinic nitrogen and quaternary nitrogen are the active sites. Due to the metal-free property of the nitrogen-rich coconut shell activated carbon, the regeneration process can be easily performed and dimethyl disulfide (CH 3 SSCH 3 ) can be recovered as the main product. Our study indicates that there is a promising prospect for nitrogen-rich coconut shell activated carbon for CH 3 SH removal because of its high capacity, mild conditions, and easy regeneration.

Preoxidation-assisted nitrogen enrichment strategy to decorate porous carbon spheres for catalytic adsorption/oxidation of methyl mercaptan

“…In addition, a small amount of pyridine-N-oxide can be created through the transformation of pyridinic nitrogen. 23 It can be also found that the relative amounts of N-6 and N-Q in the ACSN obtained by direct ammonia treatment show a little higher than those of ACSON prepared by preoxidation-assistant ammonia modication. However, the preoxidation-assistant ammonia modication introduces more nitrogen on the ACSON.…”

“…In order to investigate the created product on the surface of the exhausted carbon spheres, the exhausted samples were subjected to the thermal analysis (TA) experiments, and it can provide the information of related sulfur species through the weight loss in range of certain temperatures. 23,55 The corresponding DTG curves are shown in Fig. 6 for the exhausted carbon spheres.…”

“…Shi 22 et al proposed that doping N into the carbon nanotube (CNT) is benecial for the adsorption of S compounds through either polar or acid-base interactions, and pyridinic N and pyrrolic N improve the effects of S interaction with CNT and the capacitance, respectively. Liu 23 et al prepared nitrogen-doped coconut shell activated carbon catalysts for the removal of CH 3 SH by impregnating urea or melamine with subsequent heat treatment. The results showed that the CH 3 SH removal capacity increased with the nitrogen content, especially pyridinic nitrogen and quaternary nitrogen.…”

Valorization of Swine Manure into Hydrochars

“…The data were deconvoluted using CasaXPS (Version 2.3.18). The peak assignments and parameters for carbon, oxygen, and nitrogen were chosen based on comparable char analyses as described by [35,36].…”

Selective catalytic hydrogenation of phenol to cyclohexanone over Pd@CN: Role of CN precursor separation mode

“…The impregnation method is very common for preparing supported catalysts like Pd@CN, and the preparation conditions can significantly affect the catalytic performance, such as nitrogen source precursor, calcination temperature, Pd precursor, reduction mode, and reduction time. Melamine, dicyandiamide, urea, and ionic liquids are widely used as nitrogen source precursors. Xu et al studied the effect of different ionic liquids as nitrogen source on the catalytic activity of phenol hydrogenation.…”