title: Ultrasound-assisted extraction for total sulphur measurement in mine tailings.
abstract: A sample preparation method for percentage recovery of total sulphur (%S) in reactive mine tailings based on ultrasound-assisted digestion (USAD) and inductively coupled plasma-optical emission spectroscopy (ICP-OES) was developed. The influence of various methodological factors was screened by employing a two-level and three-factor (2(3)) full factorial design and using KZK-1, a sericite schist certified reference material (CRM), to find the optimal combination of studied factors and %S. Factors such as the sonication time, temperature and acid combination were studied, with the best result identified as 20 min of sonication, 80°C temperature and 1 ml of HNO(3):1 ml of HCl, which can achieve 100% recovery for the selected CRM. Subsequently a fraction of the 2(3) full factorial design was applied to mine tailings. The percentage relative standard deviation (%RSD) for the ultrasound method is less than 3.0% for CRM and less than 6% for the mine tailings. The investigated method was verified by X-ray diffraction analysis. The USAD method compared favorably with existing methods such as hot plate assisted digestion method, X-ray fluorescence and LECO™-CNS method.
authors.affiliation: Department of Civil and Environmental Engineering, University of Western Ontario, Canada. ad_li2@yahoo.com
authors.forename: Adnan Hossain
authors.initials: AH
authors.lastname: Khan
authors.forename: Julie Q
authors.initials: JQ
authors.lastname: Shang
authors.forename: Raquibul
authors.initials: R
authors.lastname: Alam
mesh_terms: D006851:Hydrochloric Acid / Q000737:chemistry; D007220:Industrial Waste / Q000032:analysis*; D008906:Mining; D017942:Nitric Acid / Q000737:chemistry; D013010:Sonication; D013455:Sulfur / Q000032:analysis*
chemical_list: D007220:Industrial Waste; D017942:Nitric Acid; D013455:Sulfur; D006851:Hydrochloric Acid