Limonite as a source of solid iron in the crystallization of scorodite aiming at arsenic removal from smelting wastewater

Studies on the removal of As(iii) by Fe-based materials have been carried out for decades, but the time-consuming process and low removal capacity are obstacles for large-scale practical applications.

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Arsenic Removal and Recovery from Copper Smelting Wastewater Using TiO2

Environmental Science & Technology ◽

10.1021/es1024355 ◽

2010 ◽

Vol 44 (23) ◽

pp. 9094-9098 ◽

Cited By ~ 99

Author(s):

Ting Luo ◽

Jinli Cui ◽

Shan Hu ◽

Yuying Huang ◽

Chuanyong Jing

Keyword(s):

Arsenic Removal ◽

Copper Smelting ◽

Removal And Recovery ◽

Smelting Wastewater

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Direct observation of Fe-Al-Zn ternary intermetallic compound and its transformation during the early stage of hot-dip galvanizing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151416 ◽

1993 ◽

Vol 51 ◽

pp. 1116-1117

Author(s):

C. S. Lin ◽

W. A. Chiou ◽

M. Meshii

Keyword(s):

Intermetallic Compound ◽

Reaction Rate ◽

Diffusion Rate ◽

Early Stage ◽

Zinc Bath ◽

Steel Sheets ◽

Direct Observations ◽

Solid Iron ◽

Iron And Zinc ◽

Ternary Intermetallic Compound

The galvannealed steel sheets have received ever increased attention because of their excellent post-painting corrosion resistance and good weldability. However, its powdering and flaking tendency during press forming processes strongly impairs its performance. In order to optimize the properties of galvanneal coatings, it is critical to control the reaction rate between solid iron and molten zinc.In commercial galvannealing line, aluminum is added to zinc bath to retard the diffusion rate between iron and zinc by the formation of a thin layer of Al intermetallic compound on the surface of steel at initial hot-dip galvanizing. However, the form of this compound and its transformation are still speculated. In this paper, we report the direct observations of this compound and its transformation.The specimens were prepared in a hot-dip simulator in which the steel was galvanized in the zinc bath containing 0.14 wt% of Al at a temperature of 480 °C for 5 seconds and was quenched by liquid nitrogen.

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IRON OXIDES FROM ELECTROFILTER ASH FOR WATER TREATMENT (ARSENIC REMOVAL)

Environmental Engineering and Management Journal ◽

10.30638/eemj.2009.128 ◽

2009 ◽

Vol 8 (4) ◽

pp. 895-900 ◽

Cited By ~ 2

Author(s):

Ionel Balcu ◽

Adina Segneanu ◽

Marius Mirica ◽

Mirela Iorga ◽

Catalin Badea ◽

...

Keyword(s):

Water Treatment ◽

Iron Oxides ◽

Arsenic Removal

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As(III) Removal by Dynamic Adsorption onto Amberlite XAD7 Functionalized with Crown Ether and Doped with Fe(III) Ions

Revista de Chimie ◽

10.37358/rc.19.7.7333 ◽

2019 ◽

Vol 70 (7) ◽

pp. 2330-2334

Author(s):

Mihaela Ciopec ◽

Adina Negrea ◽

Narcis Duteanu ◽

Corneliu Mircea Davidescu ◽

Iosif Hulka ◽

...

Keyword(s):

Adsorption Process ◽

Arsenic Removal ◽

Arsenic Concentration ◽

Fixed Bed ◽

World Health ◽

Arsenic Content ◽

Arsenic Adsorption ◽

Stage Of Development ◽

Wide Range ◽

Health Organization

Arsenic content in groundwater�s present a wide range of concentration, ranging from hundreds of micrograms to thousands of micrograms of arsenic per litter, while the maximum permitted arsenic concentration established by World Health Organization (WHO) is 10 mg L-1. According to the WHO all people, regardless of their stage of development and their social economic condition, have the right to have access to adequate drinking water. The most efficient and economic technique used for arsenic removal is represented by adsorption. In order to make this remediation technique more affordable and environmentally friendly is important to new materials with advance adsorbent properties. Novelty of present paper is represented by the usage of a new adsorbent material obtained by physical - chemical modification of Amberlite XAD polymers using crown ethers followed by iron doping, due to well-known affinity of arsenic for iron ions. Present paper aims to test the obtained modified Amberlite polymer for arsenic removal from real groundwater by using adsorption in a fixed bed column, establishing in this way a mechanism for the adsorption process. During experimental work was studied the influence of competing ions from real water into the arsenic adsorption process.

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Arsenic removal by MF membrane with chemical sludge adsorption and NF membrane equipped with vibratory shear enhanced process

Water Science & Technology Water Supply ◽

10.2166/ws.2003.0182 ◽

2003 ◽

Vol 3 (5-6) ◽

pp. 303-310 ◽

Cited By ~ 2

Author(s):

S.-H. Yi ◽

S. Ahmed ◽

Y. Watanabe ◽

K. Watari

Keyword(s):

Arsenic Removal ◽

Membrane Surface ◽

Membrane Process ◽

Low Concentrations ◽

Strong Shear ◽

Low Levels ◽

Removal Processes ◽

Removal Of Arsenic ◽

Concentration Polarization Layer ◽

Chemical Sludge

Conventional arsenic removal processes have difficulty removing low concentrations of arsenic ion from water. Therefore, it is very hard to comply with stringent low levels of arsenic, such as below 10 μg/L. So, we have developed two arsenic removal processes which are able to comply with more stringent arsenic regulations. They are the MF membrane process combined with chemical sludge adsorption and NF membrane process equipped with the vibratory shear enhanced process (VSEP). In this paper, we examine the performance of these new processes for the removal of arsenic ion of a low concentration from water. We found that chemical sludge produced in the conventional rapid sand filtration plants can effectively remove As (V) ions of H2AsO4- and HAsO42- through anion exchange reaction. The removal efficiency of MF membrane process combined with chemical sludge adsorption increased to about 36%, compared to MF membrane alone. The strong shear force on the NF membrane surface produced by vibration on the VSEP causes the concentration polarization layer to thin through increased back transport velocity of particles. So, it can remove even dissolved constituents effectively. Therefore, As (V) ions such as H2AsO4- and HAsO42- can be removed. The concentration of As (V) ions decreased from 50 μg/L to below 10 μg/L and condensation factor in recirculating water increased up to 7 times by using NF membrane equipped with VSEP.

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