Development and Validation of a Method for Determining Elements in Solid Waste Using Microwave Digestion

Binstock, David A.; Grohse, Peter; Gaskill, Alvia; Sellers, Charles; Kingston, H. M.; Jassie, L. B.

doi:10.1093/jaoac/74.2.360

Cited by 8 publications

(11 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Leach concentrations for SRM 2704 are not provided by NIST. All data are in the range of the NIST or other published leachable concentrations 25 with minor exceptions.…”

Section: Resultsmentioning

confidence: 99%

“…The reaction conditions and reagents have an influence on the results of the leach analysis, with a large number of different species being involved. 25,26 In this paper, we report the comparison of samples leached with controlled microwave heating to conventional hot plate heating and their ability to accurately reproduce the method's specified 95 °C temperature.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Comparison of Microwave-Assisted and Conventional Leaching Using EPA Method 3050B

and

Kingston

1996

Anal. Chem.

View full text Add to dashboard Cite

A microwave-heated EPA method 3050B for the leaching of key elements (cadmium, chromium, copper, lead, nickel, zinc) of environmental importance was tested and compared to conventional hot plate-heated EPA method 3050B. All commercially available temperature and power-controlled atmospheric pressure microwave systems were used for the adaptation of EPA method 3050B. Three temperature feedback control systems were evaluated for regulating the temperature of the leachate including outside (IR sensors) and inside the sample flask (gas bulb thermometer). Results, which show the efficiency and effectiveness of the microwave sample preparation method, are discussed for the leaching of three NIST Standard Reference Materials: 2704, 2710, and 2711. The elements were determined either using ICPMS, ET-AAS, or F-AAS. This study demonstrates that microwave heating with enhanced reaction control leads to improved precision compared to conventional heating sources.Leaching is a term that has been applied to the extraction of metals from environmental samples and has become common terminology of the EPA and in the environmental analytical field. Leaching is not a total decomposition, and leachable recoveries of analytes are generally lower than total concentrations. Recoveries can only achieve total values if an element is completely soluble in the leaching solvent. Leaching studies are an assessment of worst case environmental scenarios where components of the sample become soluble and mobile. Temperature is a key parameter for all leaching sample preparation methods as well as for extractions and digestions. The control of temperature is paramount in achieving reproducible leaching of elements. Temperature is a primary parameter used to increase the rate of leaching and to bring these tests into appropriate duration for laboratory evaluation. Previously, most leach methods have been accomplished in beakers on a hot plate. These methods are traditional, time consuming, fairly inefficient, and in general imprecise. During the early 1980s, fundamental research established temperature control as the most significant contributor to leach test error. 1,2 These experiments focused on the analysis of simulated nuclear waste glass materials. Temperature was found to be the dominant parameter in leaching uncertainty and imprecision. The control of temperature to within (0.04%, instead of (1% over a 28-day leach period, changed the interelement leaching uncertainty from 50% to 3%. By substituting microwave

show abstract

“…Leach concentrations for SRM 2704 are not provided by NIST. All data are in the range of the NIST or other published leachable concentrations 25 with minor exceptions.…”

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

Comparison of Microwave-Assisted and Conventional Leaching Using EPA Method 3050B

and

Kingston

1996

Anal. Chem.

View full text Add to dashboard Cite

show abstract

“…The excised clippings were immediately oven‐dried at 70°C for 48 h and the samples from the last collection period at the end of the study were ground for tissue analyses. For mineral analyses of K, Na, Ca, Mg, Mn, Fe, B, Cu, and Zn, the microwave‐assisted acid digestion method was used (Binstock et al, 1991). The homogenized ground samples (0.25 g) were extracted by heating with 10 mL concentrated nitric acid.…”

Section: Methodsmentioning

confidence: 99%

Nutrient Uptake Responses and Inorganic Ion Contribution to Solute Potential under Salinity Stress in Halophytic Seashore Paspalums

2007

View full text Add to dashboard Cite

There is increasing interest in superior halophytes for use on saline turfgrass, forage, and land reclamations sites. We investigated halophytic seashore paspalum (Paspalum vaginatum Swartz) ecotype responses for inorganic ion uptake in shoot tissues and to identify total and individual inorganic ion contributions to total solute potential (Ψs) adjustment under increasing salinity. In a greenhouse study, nine ecotypes varying substantially in salinity tolerance were grown in nutrient/sand culture with six salinity levels up to 49.7 dS m−1 Increasing salinity reduced uptake of K, Ca, and Mg, with Mg most affected. Sodium tissue content increased with salinity, but Cl increased and then declined as salinity increased. The least salt‐ tolerant ecotype, ‘Adalayd’, exhibited lower Cl uptake at high salinity compared to the most salt‐tolerant types (SI 93‐2, HI 101). Shoot and root growth were positively correlated to K tissue content and K was the primary ion for solute potential (Ψs) adjustment. Inorganic ions contributed 57 to 97% to Ψs adjustment with salt‐tolerant ecotypes exhibiting less dependence on inorganic ions for Ψs adjustment apparently due to their ability to maintain synthesis of organic osmolytes under high salinity. In terms of physiological traits adapted for salt‐screening protocols the following were not useful: tissue nutrient/element content; K/Na and Ca/Na tissue content ratios; and K or other ion contributions to total Ψs in percent or MPa units. Shoot tissue content relationships of K, Mg, and Ca to increasing salinity indicate the importance of nutritional programs for these nutrients on salt‐affected sites.

show abstract

“…c Results from Method 3051A validation study (). d Results from Method 3051 vs Method 3050B validation study ( , ).…”

Section: Resultsmentioning

confidence: 99%

“…The SRMs used in this study, SRM 2704 (Buffalo River Sediment), SRM 4355 (Peruvian Soil), SRM 1084a (Wear-Metals in Lubricating Oil), and SRM 1634c (Trace Metals in Fuel Oil), were purchased from the National Institute of Standards and Technology (NIST) in Gaithersburg, MD. These SRMs were also used in the study which validated EPA Method 3051A ( , ) and the round-robin study validating EPA Method 3051 against Method 3050B ( , ). Therefore, an abundance of data exists for comparison and validation of updated Method 3015A.…”

Section: Methodsmentioning

confidence: 99%

Wastewater Standards and Extraction Chemistry in Validation of Microwave-Assisted EPA Method 3015A

Link

Walter

Kingston

1999

Environ. Sci. Technol.

View full text Add to dashboard Cite

The difficulties associated with the control and transfer of environmental leach methods are discussed. Optimized EPA Method 3015A, a microwave-assisted leach of wastewater and drinking water matrices and aqueous extracts, is evaluated. The option to add HCl in addition to HNO 3 provides better complexation and recovery of certain metals that are regulated by the Resource Conservation and Recovery Act (RCRA) than the original HNO 3 -only Method 3015. Also discussed is the preparation and appropriate use of "simulated" wastewater standards. Standard reference materials for a wastewater matrix are unavailable, and this novel approach provides NIST-traceability of results for the first time on this matrix type. Leach concentrations from these "simulated" standards were determined using both the 5 mL HNO 3 and the 4 mL HNO 3 and 1 mL HCl leach options of new Method 3015A. Validation of the new mixed-acid option of Method 3015A has been provided by evaluating its performance on the 23 elements for which original Method 3015 was validated. In addition, validation is provided for boron, mercury, and strontium, elements that were not validated in original Method 3015. Method 3015A has been developed into a method capable of evaluating 26 elements in a single, efficient, 20-min procedure.

show abstract

Development and Validation of a Method for Determining Elements in Solid Waste Using Microwave Digestion

Cited by 8 publications

References 0 publications

Comparison of Microwave-Assisted and Conventional Leaching Using EPA Method 3050B

Comparison of Microwave-Assisted and Conventional Leaching Using EPA Method 3050B

Nutrient Uptake Responses and Inorganic Ion Contribution to Solute Potential under Salinity Stress in Halophytic Seashore Paspalums

Wastewater Standards and Extraction Chemistry in Validation of Microwave-Assisted EPA Method 3015A

Contact Info

Product

Resources

About