What are green extraction techniques?

In this article, only a few selective advanced techniques are discussed.

  • Pressurized liquid extraction (PLE)
  • Supercritical fluid extraction (SFE)
  • Microwave assisted extraction (MAE)
  • Ultrasound assisted extraction (UAE)
  • Enzyme assisted extraction (EAE)
  • Pulsed electric field extraction (PEF)

What is the main purpose of using Soxhlet extraction?

Typically, Soxhlet extraction is used when the desired compound has a limited solubility in a solvent, and the impurity is insoluble in that solvent. It allows for unmonitored and unmanaged operation while efficiently recycling a small amount of solvent to dissolve a larger amount of material.

How extraction process is carried out through a Soxhlet apparatus?

5.5. 1 Soxhlet extraction

  1. Solid matrix is placed in SOX thimble. Solvent is heated under reflux.
  2. Condensation and extraction with “fresh” solvent. Solutes are transferred from the extraction chamber into the reservoir.
  3. Continuous repetition of the extraction.
  4. Exhaustive extraction is complete.

Which solvent is used in Soxhlet method?

The Soxhlet extraction process heats the solvent (ethanol) to boiling temperature (>78°C). The evaporated ethanol is contained within the apparatus by the condenser unit; however the apparatus should be placed under a fume hood in case of escape.

What is green solvent extraction?

Green solvents usually are used in the enzyme-assisted extraction methodology, which are the solvents with lowest toxicity such as acetone, ethanol, methanol, 2-propanol, ethyl acetate, isopropyl acetate, methyl ethyl ketone, 1-butanol, and tert-butanol [6].

What are some modern or greener extraction methods?

Pressurised hot water extraction (PHWE) or sub-critical water is one of the most promising modern green extraction techniques and methods especially in a dynamic mode.

What is the advantage of Soxhlet extraction?

The advantages of the Soxhlet extractor are: simple and clear design, production process continuity, ease of visual monitoring of the process, a low flow of solvent and the possibility of its reuse after stripping and distillation.

Why Soxhlet apparatus is used in extraction of plant material?

Soxhlet apparatus allows isolation of desired oil even if it has limited solubility in the solvent & when other substances or impurities are insoluble in that solvent.

What are the components of Soxhlet apparatus?

A Soxhlet Extractor has three main sections: A percolator (boiler and reflux) which circulates the solvent, a thimble (usually made of thick filter paper) which retains the solid to be laved, and a siphon mechanism, which periodically empties the thimble.

Why chloroform is used in Soxhlet extraction?

Chloroform has the great advantage of being fireproof, but proper fume hoods should be used. An antifoaming agent should be added to chloroform, both in the Soxhlet apparatus and when it is redistilled. Extraction with nonpolar solvent is the only satisfactory method for determination of total lipid in most solids.