Mercury Removal from Aqueous Solutions Using Modified Pyrite: A Column Experiment

Abstract

Modified pyrite (MPy), which was obtained from calcination in an N2 atmosphere, was used as a sorbent for removing Hg(II) from aqueous solutions. Fixed-bed column experiments were conducted to determine the Hg(II) removal ability of MPy from aqueous solutions. MPy was found to be much better than natural pyrite for mercury removal. The concentration of Hg(II) in effluents was much lower than that of the emission standard used for Hg wastewater in China (0.05 mg/L), and the removal efficiency of Hg(II) was greater than 99% before breakthrough. When the capacity was 3274 times the column bed volume (1 bed volume = 25.12 cm3), the column breakthrough and the sorption amount of Hg(II) were 54.44 mg/g. The Hg(II) content in the used MPy sorbent was up to 24.79%. The mechanism was analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), field emission transmission electron microscopy (FE-TEM), and X-ray Photoelectron Spectroscopy (XPS). The main mechanism of Hg(II) removal by MPy was the chemical reactions between mercury ions and mineral fillers, and HgS precipitated on the surface of MPy to remove Hg(II). The reaction was also accompanied by surface complexation and adsorption. The results of this work show that MPy can be used as a sorbent for continuous Hg(II) removal.

Effects of Elemental Mercury Vapor Inhalation on Arterial Blood Gases, Lung Histology, and Interleukine-1 Expression in Pulmonary Tissues of Rats

“…Mercury is a highly toxic heavy metal with signi cant public health and safety implications worldwide (Ishitob et al 2010;Azevedo et al 2012;Pizzorno 2011;Bernhoft 2012;Chakraborty 2017). Mercury is commonly found in nature in many different forms (Zahir et al 2005;Bernhoft 2012; Zhu et al 2020). Inorganic mercury includes metallic mercury, mercury vapor (Hg 0 ), and mercurous (Hg + 2 ) or mercuric salts, while the organic form of mercury includes compounds containing carbon atoms such as methyl, ethyl, or phenyl groups (Costa et al 2020).…”

“…According to the World Health Organization (WHO), most human exposure to mercury occurs through the inhalation of elemental mercury vapor via occupational or dental amalgam exposure (WHO 1991;Zhu et al 2020).…”

“…The ingestion of seafood contaminated with organic mercury has been reported as another major route via which people are exposed to mercury (Zhu et al 2020). Although mercury is present naturally in the environment, recent human industrial activities have resulted in the dangerous accumulation of more mercury in the land, water, and food supplies (Clarkson 2008;Zhu et al 2020). This accumulation of mercury in the environment carries grave health risks and consequences.…”

“…Acute severe exposure to elemental mercury vapor has been reported to lead to fatality as a result of pulmonary insu ciency and acute renal failure (Asano et al 2000). Generally, mercury exposure is chronic at a low dosage resulting in subtle toxic manifestations characterized by loss of appetite, weakness, malaise, loss of weight, and gastrointestinal upset (Bernhoft 2012;Zhu et al 2020). However, in the acute form, more severe manifestations related to the immune system, gastrointestinal tract, renal, cardiopulmonary, and nervous systems have been reported (Houston 2011;Bernhoft 2012).…”

Effects of Elemental Mercury Vapor Inhalation on Arterial Blood Gases, Lung Histology, and Interleukin-1 Expression in Pulmonary Tissues of Rats

“…According to the World Health Organization (WHO), most human exposure to mercury occurs through the inhalation of elemental mercury vapor via occupational or dental amalgam exposure [ 7 , 10 ]. The ingestion of seafood contaminated with organic mercury has been reported as another significant route to expose people to mercury [ 7 ].…”