Coated sand filtration: an emerging technology for water treatment

Natural speciation of Ni, Zn, Ba, and As in ferromanganese coatings on quartz using X-ray fluorescence, absorption, and diffraction

“…Here, focus is placed on the structural chemistry of metal(loid)s-containing ferrihydrite and vernadite formed naturally at the surface of quartz grains from sand filters used in groundwater treatment plants. These samples were chosen because oxide-coated silica sand commonly is used for water purification due to its high hydraulic conductivity and low cost (e.g., Cheremisinoff, 1995;Babel and Kurniawan, 2003;Qureshi and Nelson, 2003;Vaishya and Gupta, 2003;Hu et al, 2004a,b) and studied in the laboratory especially for application in household arsenic removal systems (Thirunavukkarasu et al, 2001(Thirunavukkarasu et al, , 2003Bose and Sharma, 2002;Yuan et al, 2002;Vaishya and Gupta, 2004;Gupta et al, 2005;Jessen et al, 2005;Kundu and Gupta, 2005;Leupin and Hug, 2005;Newcombe et al, 2006). Fundamental understanding of the structure of the sorbent phases and of the partitioning and retention mechanisms of toxic elements (here, Ni, Zn, As, and Ba, an analogue for Ra) should benefit the design and use of engineered field systems.…”

Adsorption of As(III) from aqueous solutions by iron-impregnated quartz, lignite, and silica sand: kinetic study and equilibrium isotherm analysis

“…Chronic health effects of arsenic include, development of various skin lesions, such as hyper pigmentation dark spots, hypo pigmentation white spots, keratoses, corns, and small warts of the hands and feet. Skin cancers and internal cancers $lung, kidney, liver, and bladder can appear due to high arsenic exposure [1][2][3][4]6]. Humans may be exposed to arsenic mainly through food and water, particularly in certain areas, where the groundwater is in contact with arsenic-containing mineral [1][2][5][6][7].…”

“…Skin cancers and internal cancers $lung, kidney, liver, and bladder can appear due to high arsenic exposure [1][2][3][4]6]. Humans may be exposed to arsenic mainly through food and water, particularly in certain areas, where the groundwater is in contact with arsenic-containing mineral [1][2][5][6][7]. Studies have reported that people exposed to high levels of arsenic are having severe health problems in many countries like Argentina, India, Pakistan, Mexico, Germany, Bangladesh, USA, Canada, America, Hungary, Nepal, Myanmar, Cambodia, etc [6][7][8].…”

“…The water contaminated with enormous quantities of heavy metals as pollutants is being released by various industries because of the broad range of applications of heavy metals among the top chemical compounds used in many industries. Out of many heavy metalloids, arsenic is of major concern as an environmental pollutant due to its recalcitrant and toxic nature [1][2][3][4][5]. Leaching from geological formations is a major natural source of arsenic in *Corresponding author.…”

Research on Removal of Manganese in Drinking Water by Ferric Oxyhydroxides Composites

“…At this point, the addition of oxidants can remove pollutants more efficiently. But the mature time of manganese sand is difficult to control, and the effect is not good when dealing with high concentration raw water [2] [3] . Hydroxy iron oxide is a kind of iron oxide with large specific surface area, fine particle structure and stable properties.…”