Cd(II) adsorption from aqueous solutions using modified attapulgite
- PDF / 763,985 Bytes
- 12 Pages / 439.37 x 666.142 pts Page_size
- 42 Downloads / 229 Views
Cd(II) adsorption from aqueous solutions using modified attapulgite Yun He1 · Xiaokai Sun1 · Pu Zhang1 · Feifei Wang1 · Zhenzhen Zhao1 · Chiquan He1 Received: 5 May 2020 / Accepted: 20 June 2020 © Springer Nature B.V. 2020
Abstract In order to obtain a high removal efficiency of Cd(II) in aqueous solution, natural attapulgite (ATP) was modified with hydrochloric acid (HCl), octadecyl trimethyl ammonium chloride, nitrilotriacetic acid (NTA), and ethanediamine (EDA) to develop an effective Cd(II) adsorbent. The characteristics of the modified adsorbents and the natural ATP were characterized using scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The adsorption kinetics of Cd(II) in aqueous solution were well described by a pseudo-second-order kinetic equation, and the sorption isotherm most closely followed the Langmuir model. Complexation was determined to be the main adsorption mechanism. Among the four modified ATPs, EDA-ATP (ATP modified by EDA) showed the best adsorption capacity for Cd(II), reaching 10.55 mg g−1, which was 115 and 27 percentages higher than the capacity of the unmodified ATP and NTA-ATP (ATP modified by NTA), respectively. The ionic strength and pH of the initial solution had no significant impact on the adsorption capacities of Cd(II) onto EDA-ATP. The EDA-ATP loaded with Cd(II) could be regenerated easily by acid treatment. These results give an available choice for the effective and recyclable Cd(II) ions sorbents from water. Keywords Attapulgite · Acidic modification · Cd(II) · Adsorption · EDA-ATP
Introduction The rapid development of industry has increased the pollution of heavy metals worldwide, which would discharged great amount of heavy metals and endanger the environment and human health [1, 2]. Typical heavy metal pollutants, such as Electronic supplementary material The online version of this article (https://doi.org/10.1007/s1116 4-020-04201-z) contains supplementary material, which is available to authorized users. * Chiquan He [email protected] Extended author information available on the last page of the article
13
Vol.:(0123456789)
Y. He et al.
cadmium (Cd(II)), come from modified industrial sources, such as the metal finishing, textiles, mining, plating, and ceramics. Due to its harmful effects to humans and the ecosystem, the removal of Cd(II) from wastewater has become a hot topic recently. Various techniques have been proposed to remove Cd(II) in aqueous solution, including membrane filtration, coagulation co-precipitation, precipitation, ionic exchange, and adsorption [3–5]. Due to the simplicity of operation, the low costs, and the low energy cost, adsorption has been extensively studied [6, 7]. Attapulgite (ATP) is a kind of natural crystalline hydrated magnesium aluminum silicate mineral with a fibrous morphology [8]. ATP has been always used as an effective and economic adsorbent used in wastewater treatment [9]. What’s more, the application of ATP to the adsorption of heavy metal ions from wastewater has also b
Data Loading...
