Optimization of experimental factors on iodate adsorption: a case study of pomelo peel
- PDF / 2,149,850 Bytes
- 13 Pages / 595.276 x 790.866 pts Page_size
- 18 Downloads / 177 Views
Optimization of experimental factors on iodate adsorption: a case study of pomelo peel Tianxing Da1,2 · Tao Chen1,2 Received: 6 May 2020 © Akadémiai Kiadó, Budapest, Hungary 2020
Abstract This article focuses on the efficient removal of iodate by pomelo peel, a low-cost biosorbent. The Langmuir and Pseudofirst-order model are the best fit models. The response surface methodology (RSM) was also used to find the optimal experimental factors and their correlations. The maximum adsorption capacity can reach 6.91 mg g−1 under the optimal factors. The dominant mechanism is physical adsorption and the oxygen-containing groups of pomelo peel play a decisive role in adsorption. Pomelo peel could be an efficient, economical and eco-friendly iodate adsorbent and RSM is valuable in the research of radioactive waste treatment. Keywords Response surface methodology · Biosorbent · Radioactive waste · Iodate
Introduction 129
I is a major fission product of nuclear power plant with a long half-life of 15.7 × 106 years, which is considered as a hazardous radionuclide because of its high toxicity and mobility in the environment. It is necessary to find an efficient method for removing 129I from the environment. Inorganic iodine in the environment mostly exists in the form of iodide (I−) and iodate (IO3−). Shortly after the 2011 Fukushima nuclear power plant accident, a certain proportion of 129 IO3− was detected from the aerosol sample collected in Tsukuba, Japan [1]. At Handford Site in USA, total iodine is dominant by the presence of iodate [2]. There are two strategies for iodate removal. One strategy is to first reduce iodate to iodide and then selectively remove iodide, the materials applied including organoclay, granular activated carbon, silver functionalized silica aerogel, and bismuth functionalized graphene oxide [3–5]. The other strategy is to directly remove iodate, such as using hydrous γ-Al2O3, hydrotalcite, * Tao Chen [email protected] 1
School of Nuclear Science and Engineering, North China Electric Power University, Beijing 102206, China
Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy, North China Electric Power University, No. 2 Beinong Road, Changping District, Beijing 102206, China
2
CoCr-4NC and B i2O3 [6–9]. An adsorbent may be effective in laboratory studies. However, the practical application is still challenged by cost, toxicity, durability and other problems. There is still room to improve the adsorption of iodate and the seeking for better iodate adsorbent is endless. Pomelo is the largest citrus fruit, popular in Asia, with extremely a high yield of 5 million ton per year. Pomelo peel accounts for about 20% of the total mass, which is discarded as waste. Pomelo peel has good adsorption ability to heavy metal ions such as Zn2+, Pb2+, Cr3+, Cu2+ and Ni2+ [10–12]. It is also used to remove dyes, organic wastewater and petroleum contaminants [13–16]. Pomelo peel is rich in cellulose, lignin, and pectin, so it has a large amount of hydroxyl and carbonyl groups [17
Data Loading...
