Use of Carbon Nanofibers in the Removal of Organic Solvents from Water

Abstract

Catalytically grown carbon nanofibers are a set of novel structures that are produced by the decomposition of selected carbon-containing gases over metal particles. These conformations consist of nanosized graphite platelets separated a distance of at least 0.34 nm and stacked in various orientations with respect to the fiber axis. Such an arrangement results in a unique structure that is composed of an infinite number of extremely short and narrow pores, suitable for the sequestering of small molecules. We have attempted to capitalize on this blend of properties by using such structures for the selective removal of organic contaminants from aqueous streams. Experimental results indicate that nanofibers possessing a structure in which the graphite platelets are aligned perpendicular to the fiber axis and possessing a high degree of structural perfection exhibit superior selective adsorption properties with respect to removal of alcohols from aqueous media over those displayed by active carbon. Adsorption was enhanced when the carbon nanofibers were initially subjected to a treatment in 1 M hydrochloric acid. In contrast, when this step was carried out in the presence of 1 M nitric acid, the beneficial properties of the nanofibers were effectively suppressed. An analogous series of experiments carried out with nanofibers possessing a structure in which the graphene layers were oriented at an angle with respect to the fiber axis did not result in the same degree of selective capture of the alcohols. A rationale is presented to account for this diverse pattern of behavior.

Synthesis and Characterization of Carbon Nanofibers Produced by the Floating Catalyst Method

“…Furthermore, herringbone structures are believe to form when the catalyst particle is made of an alloy. 40,41 The results obtained using energy-filtered TEM (EFTEM) are consistent with those achieved by X-ray analysis. EFTEM has been shown to be an efficient tool for the acquisition of species sensitive chemical distribution maps.…”

Production of COX Free Hydrogen by Catalytic Decomposition of Methane Over Ni/HY Catalysts

“…On economical perspective the H 2 production rate and the CNF or CNT synthesis are equally important. Due to unique properties of the CNTs and CNFs [2,7] they are emerged as potential components in various applications such as catalyst supports [8][9][10], hydrogen storage materials [11], electronic and mechanical devices [12], composite materials [13] and adsorption/absorption agents [14]. Choudhary et al have studied the nature and type of carbon formed during methane decomposition over Ni based catalysts [15].…”

Growth of Filamentous Carbon from the Surface of Ni/SiO2 Doped with Alkali Metal Bromides

“…Such ordered carbon structures possess unique chemical and physical properties that can be exploited in adsorption (13), catalysis (14)(15)(16), hydrogen storage (17)(18)(19), and electronics applications (20,21). The work reported herein focuses on the application of alkali bromide doped Ni-supported catalysts to generate structured carbon filaments from a model C 2 H 4 /H 2 feedstock.…”