Extraction of organic material in mineral coal by using supercritical fluid extraction, soxhlet, and sonication methods

✍ Scribed by Maria G. R. Vale; Luiza P. Luz; Ayrton F. Martins; Elina B. Caramão; Cláudio Dariva; José V. de Oliveira

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 142 KB
• Volume: 10
• Category: Article
• ISSN: 1040-7685
• DOI: 10.1002/(sici)1520-667x(1998)10:3<259::aid-mcs4>3.0.co;2-f

✦ Synopsis

Soxhlet and sonication techniques have been widely used for extracting semivolatile organic compounds from solid matrices regardless of the fact that these methods are time consuming and costly in amount of solvent required. In recent years, supercritical fluids have gained increased interest as extraction solvents for organic compounds due to their unique and well-known properties. This article describes the preliminary results of the use of Soxhlet, sonication, and Ž . supercritical fluid extraction SFE methods for the recovery of organic compounds from a high-ash Brazilian mineral coal. In both Soxhlet and sonication extractions the solvent was dichloromethane. Supercritical isopropanol was utilized for SFE.

Ž . The extracts were fractionated by the preparative liquid chromatography PLC-8 method into eight well-defined fractions. Although all three extracts presented almost the same qualitative profile, SFE was more efficient than Soxhlet and sonication extractions. Moreover, SFE was faster and more convenient than the two conventional methods. Quantitative analyses are being carried out and will be presented elsewhere.