A study on the removal of arsenic from real life groundwater using iron-chitosan composites is presented. Removal of arsenic(III) and arsenic(V) was studied through adsorption at pH 7.0 under equilibrium and dynamic conditions. The equilibrium data were fitted to Langmuir adsorption models and the various model parameters were evaluated. The monolayer adsorption capacity from the Langmuir model...

A new arsenic removal process was designed combining: 1) iron nanoparticle addition, b) electrocoagulation, and c) electromagnetic separation. Results showed that arsenic could be removed with more than 99 % efficiency from liquid waste samples. Parameters that were found to have importance on the process were: a) nanoparticle dosage, b) electric voltage drop during electrocoagulation, b) pH of...

In Bangladesh, arsenic contamination of groundwater, microbial contamination of surface water and seasonally variable rainfall make reliable access to acceptable quality drinking water a challenge. Arsenic-iron removal plants (AIRPs) are a relatively inexpensive way of removing arsenic from groundwater for access to safer drinking water. This study evaluated the performance of 21 (of 105) AIRPs...

Arsenic's history in science, medicine and technology has been overshadowed by its notoriety as a poison in homicides. Arsenic is viewed as being synonymous with toxicity. Dangerous arsenic concentrations in natural waters is now a worldwide problem and often referred to as a 20th-21st century calamity. High arsenic concentrations have been reported recently from the USA, China, Chile, Banglade...

Arsenic contamination of drinking water is a serious public health threat. In Bangladesh, eight major safe water options provide an alternative to contaminated shallow tubewells: piped water supply, deep tubewells, pond sand filters, community arsenic-removal, household arsenic removal, dug wells, well-sharing, and rainwater harvesting. However, it is uncertain how well these options are accept...

Arsenic is the most toxic metalloid present in the natural environment in both organic and inorganic arsenic forms. Inorganic arsenic is often more hazardous than the organic form. Arsenite and arsenate compounds are the major inorganic forms which are toxic causing severe human health dysfunction including cancer. Excretion of arsenic from the system is found elusive. Therefore, it is of inter...

A new regulation has been proposed that would lower the acceptable level of arsenic in drinking water from the current standard of 50 ppb. Therefore, research into effective arsenic removal treatment is important, especially for hard to treat waters with high concentrations of silica. The first phase of research was designed to determine if sand ballasted coagulation is a viable means of removi...

To explore the feasible treatment alternatives for organic contaminant, especially organic arsenic species in the landfill gas (LFG) condensate, a variety of treatment approaches were examined and evaluated in this study. Biological degradation, conventional and advanced oxidation, and physical absorption showed limited effectiveness to convert the methylated arsenic to inorganic arsenic. Rever...

Human activities and natural processes release arsenic into ground and surface waters creating potentially serious environmental problems for humans and other living organisms [1]. In recognition of this threat, a new arsenic limit of 10lg/l, lowered from the current 50g/l, will become effective in 2006 for drinking water systems in the United States. Consequently, there is an urgent demand for...