Abstract
Background: In the growing environmental concerns, use of of natural products, efficient processes and devices are necessary. Solid-Liquid extraction of active ingredients from plant materials is one of the important unit operations in Chemical Engineering and needs to be enhanced.
Objectives: These active ingredients are firmly bound to the plant cell wall membrane, which poses mass-transfer resistance and needs to get detached by using suitable process intensification tools such as ultrasound and suitable devices. Therefore, detailed analysis and review are essential for development made in this area through Publications and Patents. Hence, the present paper illustrates the development of an ultrasound-assisted device for solid-liquid extraction.
Methods: Advantages such as percentage yield, reduction in extraction time, use of ambient conditions, better process control and avoidance or minimizing multi-stage extraction could be achieved due to the use of ultrasound in extraction compared to conventional processes.
Conclusions: The use of ultrasound to provide significant improvements in the extraction of Vegetable tannins and natural dyes for application in leather processing has been demonstrated and reported earlier. These enhancements could be possible through various effects of ultrasound such as the better flow of solvents through micro-jet formation, mass transfer enhancement due to rupture of plant cell wall membranes through acoustic cavitation, better leaching due to micro-mixing and acoustic streaming effects. This approach would minimize material wastage; thereby, leading to eco-conservation of plant materials, which is very much essential for a better environment. Hence, various methods and designs for the application of ultrasound-assisted solid-liquid extractor devices are necessary.
Keywords: Solid-liquid extraction, process intensification, ultrasound, leaching, extractor device, plant materials, leather processing.
Graphical Abstract
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