Location: Commodity Utilization Research2013 Annual Report
1a. Objectives (from AD-416):
This project has an objective to study how ARS-manufactured carbons can be used to adsorb heavy metals and chlorinated organics in contaminated sediments. This adsorption may cause the contaminants to be less available to biota.
1b. Approach (from AD-416):
ARS will test ARS-manufactured activated carbons on surrogate wastewaters. The "best" carbons will be forwarded to the collaborator at University of Maryland. The collaborator will test the activated carbons in a sediment matrix for adsorption capabilities and for reduced contaminant bioavailability.
3. Progress Report:
This the final progress report. ARS produced activated carbons from turkey and chicken litter according to standard principles published in J. Resid. Sci. Technol. 3(3):161-167 in 2006. The activated carbons were tested for their ability sorb copper, mercury, lead, zinc, and cadmium ions (metals that were selected after consultation with UMBC) from a buffered water solution. The results on the metals uptake were provided to the collaborator together with a brief description of the procedure by which the tests were performed. Approximately 100 grams of each of the activated carbon samples were sent to UMBC. This is part of an unfunded voluntary effort at UMBC to evaluate the feasibility of using activated carbons made from poultry litter in the remediation of contaminated sediments. Adsorption studies with mercury were conducted with the activated carbons obtained from ARS along with a range of other commercially available activated carbons and biochars. In addition, the activated carbons and biochars were amended to mercury contaminated sediment obtained from a Department of Defense Superfund site to evaluate the effectiveness of the carbons in reducing the methylation of mercury and bioavailability of mercury and methylmercury to the lake organism Leptocheirus plumulosus (a small freshwater shrimp-like animal). The collaborator preliminary concluded that the char made by USDA-ARS out-performed all the other char materials tested as it pertained to removal of mercury from water. Also, significant progress has been made in taking sediment remediation technologies in the field. A feature 2011 article (“In-situ sorbent amendments: A new direction in contaminated sediment management” in Environ. Sci. Technol. 45: 1163-1168) published by the UMBC collaborator summarized the development of the work on activated carbons and biochars and how the effort is leading to pilot-scale studied being performed at various sites in the country and in Norway. All planned work has been completed.