Click to enlarge
January 18, 2006 Two arsenic removal papers by Stevens professor make ScienceDirect's top 25
Two papers by Xiaoguang Meng, Director of Technical and Academic Development, Center for Environmental Systems at Stevens Institute of Technology, and postdoctoral research associate Sunbaek Bang were among ScienceDirect's top 25 papers published in 2005. Removal of arsenic from water by zero-valent iron, written with George P. Korfiatis, Dean of Stevens Charles V. Schaefer, Jr. School of Engineering and McLean Chair Professor is number 14 in the Journal of Hazardous Materials top 25 articles of 2005. Following is an abstract of the paper :
Batch and column experiments were conducted to investigate the effect of dissolved oxygen (DO) and pH on arsenic removal with zero-valent iron [Fe(0)]. Arsenic removal was dramatically affected by the DO content and the pH of the solution. Under oxic conditions, arsenate [As(V)] removal by Fe(0) filings was faster than arsenite [As(III)]. Greater than 99.8% of the As(V) was removed whereas 82.6% of the As(III) was removed at pH 6 after 9 h of mixing. When the solution was purged with nitrogen gas to remove DO, less than 10% of the As(III) and As(V) was removed. High DO content and low solution pH also increased the rate of iron corrosion. The removal of arsenic by Fe(0) was attributed to adsorption by iron hydroxides generated from the oxic corrosion of Fe(0). The column results indicated that a filtration system consisting of an iron column and a sand filter could be used for treatment of arsenic in drinking water.
A link to the full paper is at here
The second paper, Removal of arsenic from groundwater by granular titanium dioxide adsorbent, by Drs. Meng and Bang, along with Manish Patel and Lee Lippincott of the New Jersey Department of Environmental Protection, is number 10 in Chemosphere's top 25 articles of 2005 . The abstract is below:
A novel granular titanium dioxide (TiO 2) was evaluated for the removal of arsenic from groundwater. Laboratory experiments were carried out to investigate the adsorption capacity of the adsorbent and the effect of anions on arsenic removal. Batch experimental results showed that more arsenate [As(V)] was adsorbed on TiO 2 than arsenite [As(III)] in US groundwater at pH 7.0. The adsorption capacities for As(V) and As(III) were 41.4 and 32.4 mg g −1 TiO 2, respectively. However, the adsorbent had a similar adsorption capacity for As(V) and As(III) (approximately 40 mg g −1) when simulated Bangladesh groundwater was used. Silica (20 mg l −1) and phosphate (5.8 mg l −1) had no obvious effect on the removal of As(V) and As(III) by TiO 2 at neutral pH. Point-of-entry (POE) filters containing 3 l of the granular adsorbent were tested for the removal of arsenic from groundwater in central New Jersey , USA . Groundwater was continuously passed through the filters at an empty bed contact time (EBCT) of 3 min. Approximately 45 000 bed volumes of groundwater containing an average of 39 μg l −1 of As(V) was treated by the POE filter before the effluent arsenic concentration increased to 10 μg l −1. The total treated water volumes per weight of adsorbent were about 60 000 l per 1 kg of adsorbent. The field filtration results demonstrated that the granular TiO 2 adsorbent was very effective for the removal of arsenic in groundwater.
A link to the full text of this paper is at here