Removal and Adsorption of p‐Nitrophenol from Aqueous Solutions Using Carbon Nanotubes and Their Composites

Abstract

In an attempt to explore the possibility of using carbon nanotubes (CNTs) as efficient adsorbents for removal of pollutants from the contaminated water, the adsorption ofp-nitrophenol (PNP) on raw multiwalled carbon nanotubes (r.MWNTs) with different outer diameters, various functionalized multiwalled carbon nanotubes (f-MWNTs), raw single-walled carbon nanotubes (r.SWNTs) and oxidized single-walled carbon nanotubes (ox-SWNTs) has been investigated. The ox-SWNTs showed better adsorption ability for PNP with different concentrations, while lower uptake capacity was found for all of the r.MWNTs andf-MWNTs. The removal efficiency of PNP by ox-SWNTs was around 98%, indicating that ox-SWNTs possess a great potential application prospect for removing PNP from aqueous solutions.

Removal of p-Nitrophenol from Aqueous Solution Using Brazilian Peat: Kinetic and Thermodynamic Studies

“…The q max values decreased from 23.39 to 16.10 mg g −1 as a function of temperature (Table 2). Moreover, these q max values are quite significant for PNP removal when compared to surfactant-modified clinoptilolite-polypropylene hollow fibre composites, nano-titanium dioxide and bismuth ferrocyanide, as can be seen in Table 3 (Nouri and Hagheseresht 2004;Krasil'nikova et al 2008;Mehrizad et al 2012;Motsa et al 2012;Yao et al 2014;Ofomaja and Unuabonah 2013;Tewari 2014). The values of K L and K F , as well as their correlation coefficients, r F and r L , are shown in Table 2.…”

“…These results suggest that the adsorption of PNP onto peat is controlled by external mass transfer followed by intraparticle diffusion mass transfer Table 1 Kinetic parameters and intraparticle diffusion for PNP removal using a peat adsorbent T (°C) C 0 (mg L −1 ) q e,exp (mg g −1 ) Pseudo-first-order Pseudo-second-order Intraparticle diffusion (Arasteh et al 2010). The values of C can determine the boundary thickness, as larger C values correspond to greater boundary layer diffusion effects (Yao et al 2010(Yao et al , 2014. According to Table 1, C and k i values decreased with increasing temperature (15-25°C) in the concentration range of 600-1200 mg L −1 .…”

Adsorptive Removal of Phenol from Aqueous Solution by Using Carbon Nanotubes and Magnetic BioChar

“…Environmental Protection Agency (EPA) has set a limit of 0.1 mg/L of phenol in wastewater odor threshold at 0.04 ppm. The World Health Organization sets a 0.001 mg/l of phenol in potable water [8][9][10][11][12].…”

Catalytic Ozonation: An Advanced Strategy for the Removal of Nitro Phenols from Contaminated Water

“…Removal of nitrophenols by ozonation and adsorption are studied individually [9,10]. In this study, a combination of both is tried and laboratory scale standardization is achieved.…”