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ENVIRONMENTAL ANALYSIS I. Solid Phase Extraction. introduction sample preparation overview. Basic Principles of SPE. Sample Preparation Overview Fundamentals of SPE Sorbent Selection in SPE Various Modes of SPE Packed Bed vs. Disk vs. Tip Format The use of Dual Phases
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ENVIRONMENTALANALYSISI. Solid Phase Extraction introduction sample preparation overview
Basic Principles of SPE • Sample Preparation Overview • Fundamentals of SPE • Sorbent Selection in SPE • Various Modes of SPE • Packed Bed vs. Disk vs. Tip Format • The use of Dual Phases • Step by Step Method Development
Recent Developments in SPE • Resin-Based Sorbents • Carbon-Based Sorbents • ISOLUTE HM-N Sorbent • Phase Separators • MSPD: Matrix Solid Phase Dispersion • Dispersive SPE
Applications • EPA 1664: O & G • EPA 525.1 Analytes • Extraction of Triazines • Extraction of PAHs • Multiresidue Method for Pesticides
Sample Preparation • THE GOAL • Prepare sample for a particular analytical technique • Interference removal • Concentration • THE BASIS • Phase transfer
Phase Choices Liquid Vapor Distillation Soln. Solid Precipitation Soln. Soln. L/L extraction Soln. Surface Liquid sorption Vapor Surface Gas sorption Solid Soln. Soxhlet Solid Fluid SFE
1 K( ) + 1 VORG VAQ Phase Transfer Efficiency n % E = 100 x • Phase Ratio: b = (VORG / VAQ)
L / L Extraction • Two extraction solvents per step • Solvents must be immiscible • Non-selective extraction • Emulsion • Large solvent volumes • Extract concentration required • Serial process; largely manual
Continuous L/L Extraction Likens-Nickerson apparatus
Continuous L/L Extraction Nielsen-Kryger apparatus
Solid Phase Extraction • Sorbent-phase and Liquid-phase • Inherent immiscibility • Selective extraction • No emulsions • Small solvent volumes • Inherent concentration • Batch process
Interference Removal(1) before.. after DIOL SPE
Interference Removal(2a) 10g sample after ENV+ extraction
Interference Removal(2b) ENV+ extract after PRS clean-up