Nano ferric oxide adsorbents with self-acidification effect for efficient adsorption of Sb(V). (June 2021)

• Record Type: Journal Article
• Authors: Feng, Xiuping; Yan, Ruixin; Zhang, Qinggang; Wan, Qun; Hagio, Takeshi; Ichino, Ryoichi; Kong, Long; Cao, Xinde; Li, Liang
• Is Part Of: Chemosphere. Volume 272(2021)
• Publication Date: 2021-06
• Subjects: Sb(V) removal -- Nano ferric oxide -- Self-acidification -- Adsorption -- Mechanism analysis; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.129933
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: It is urgent and essential to remove antimony from wastewater due to its potential carcinogenicity. In this paper, a nano ferric oxide (NFO) adsorbent was synthesized in a one-step low temperature calcination (150 °C) process. It presents a surprising self-acidification behavior, could automatically adjust the pH to around 4 from different intimal pH values (4–9), which enable it to efficiently remove more than 99% of Sb(V) from wastewater in a wide pH range. X-ray photoelectron spectroscopy analysis proved that the self-acidification function was originated from the hydrolyzation of surface Fe atoms on ferric oxide nanoparticles. The maximum adsorption capacity of this adsorbent is 78.1 mg/g which is 2–3 times higher than that of the samples obtained at higher temperatures (250 °C and 350 °C), and also its adsorption kinetic constant is ten times higher, which can be attributed to the larger surface areas and smaller sizes of ferric oxides synthesized at 150 °C. In the actual wastewater treatment, the effluent's concentration after treatment can be maintained below the instrument detection limit even under low initial antimony concentration. We believe that this new adsorbent has great potential in the practical application in the treatment of Sb polluted wastewaters due to its simple synthesis, high efficiency, and low cost. Highlights: Nano ferric oxide (NFO) achieved by simple one step calcining at 150 °C. NFO has excellent Sb(V) removal efficiency above 99% in wide pH range. NFO shows an obvious self-acidification behavior. The antimony can be effectively removed from realistic wastewater by NFO.