Maximization of Carbon Nanohorns Production via the Arc Discharge Method for Hydrotreating Application

Abstract

The submerged arc in liquid nitrogen method was used to produce carbon nanohorns (CNH) for hydrotreating application. In this paper the effects of current, time and system design modification were investigated to maximize CNH production. A current setting of 90 A was found to be the best condition for CNH production. Additionally, CNH production was impacted by processing time and design setup used in synthesizing the samples. For each batch, 0.12 g of CNH was obtained for 30 mins of processing time. The properties of CNH were evaluated using Brunauer–Emmett–Teller (BET) method, transmission electron microscopy (TEM), Fourier transform infrared (FTIR), Raman Spectroscopy and X-ray diffraction (XRD). BET results revealed mesoporous pore diameters for all pristine CNH samples under the different current (50–100 A) settings. Dahlia-like and budlike structures with aggregate diameters ranging from ~50–110 nm were observed in the TEM images. Although current and processing times were found to be two crucial parameters affecting the yield of CNH production, the entire equipment design was a major key factor in improving the yield by being capable of retaining more CNH particles during production.

Comparative Studies of Carbon Nanomaterial and γ-Alumina as Supports for the Ni–Mo Catalyst in Hydrotreating of Gas Oils

“…The carbon support materials used in this study, i.e., carbon nanohorns (CNH) and other carbon particles (OCP) were simultaneously generated from the arc-discharge process, and these supports were distinguished based on a filtration process after an arc-discharge experiment. A current setting of 90 A was used and detailed information about the experimental setup and reaction conditions have been previously reported . US No.…”

“…A current setting of 90 A was used and detailed information about the experimental setup and reaction conditions have been previously reported. 21 US No. 50 standard sieve series, which corresponds to 300 micron average particle diameter, was used to set the cutoff for OCP f (i.e., fine fraction of OCP) support.…”

Carbon Nanohorns as Effective Nanotherapeutics in Cancer Therapy

“…In particular, the dahlia-like CNH, spherical structure with a diameter of 80-100 nm composed of nearly 2000 tubular unites, are the most frequently used in nano-oncology applications (Figure 2) [61,62]. The synthesis of CNH is based on the vaporization of a carbon substrate (e.g., graphite) in the absence of any metal catalyst, and the subsequent quenching in an inert atmosphere [65]. Depending on the energy source employed in the vaporization step, three main synthetic methods can be described, namely arc discharge, laser ablation, and joule heating.…”

“…In all cases, the absence of metal impurities results in a purification step consisting of thermal annealing to remove carbon impurities (in the form of graphite microparticles, fullerenes, giant carbon onions, and amorphous carbon) which results in a remarkably reduced toxicity in biomedical applications [45,66]. This is one of the main advantages of CNH when compared to CNT, alongside the greater specific surface area, higher porosity and higher diameter which allows the free movement of encapsulated molecules and the The synthesis of CNH is based on the vaporization of a carbon substrate (e.g., graphite) in the absence of any metal catalyst, and the subsequent quenching in an inert atmosphere [65]. Depending on the energy source employed in the vaporization step, three main synthetic methods can be described, namely arc discharge, laser ablation, and joule heating.…”