On-line microwave-assisted digestion of solid samples for their flame atomic spectrometric analysis

Comparative study on open system digestion and microwave assisted digestion methods for metal determination in shrimp sludge compost

“…Microwave digestion procedures are classified according to their operational modes; open vessel microwave assisted digestion, which is more prone to sample contamination, and susceptible to losses of volatile metals and closed (pressurised) vessel procedures, which are rapid and efficient digestion techniques. On line microwave assisted digestion of solid samples and a combination with ultrasonic radiation also are known [36,37].…”

Automatic flow-injection system for the determination of heavy metals in sewage sludge by microwave digestion and detection by inductively coupled plasma-atomic emission spectrometry (MW-ICP/AES)

“…Many of these problems can be avoided or at least alleviated if the process is carried out by the flow injection methodology (FIA) [18]. Several authors have achieved satisfactory results using the FIA methodology to combine the microwave sample treatment with atomic spectrometric detection (i.e., FAAS, ICP/AES) [19][20][21][22][23][24][25][26][27]. Burguera et al [19] used an FIA flow-merging manifold for the FAAS determination of Cu, Zn and Fe in blood.…”

“…The mean values obtained for both elements were similar in all three cases, whereas the dispersion of the values was greater for the on-line system. Burguera and Burguera [26] used an MW-ETA combination for the determination of Pb in biological samples, with a digestion time of 25 s and P"700 W. De la Guardia et al [21,23,25] applied microwave radiation to the decomposition of sewage sludge by means of two configurations, (1) closed flow injection systems [21,23] and (2) mergingflow/on-line MW digestion [25], using FAAS to carry out the elemental analysis. Using configuration (1) they got quantitative recoveries for Pb, Cu and Mn in a digestion time of 4-5 min, whereas with configuration (2) the quantitative recovery for the same elements plus Zn was reached in a digestion time of about 5 min and with P"650 W, depending on the experimental conditions (i.e., length and inner diameter of the capillary, and flow).…”

Direct Introduction of Slurry Samples in Multi-syringe Flow Injection Analysis: Determination of Potassium in Plant Samples

“…Another alternative for the direct introduction of solids into flow systems is the introduction of powdered or disperse solids as slurries. 7 This approach has been applied to the direct insertion of plant samples into flow systems by means of injection valves/ commutators [8][9][10] or selection valves. 11,12 The use of pinch valves for the same aim was reported in theoretical studies using model solutions 13 and a nitrogen flow to propel the slurry samples, 14 without application to real samples.…”