Application of biosurfactants for heavy netals leaching from immobilized activated sludge / Zastosowanie biosurfaktantów do wymywania metali ciężkich z immobilizowanego osadu czynnego

Abstract

This study was undertaken to determine the effectiveness of biosurfactants -saponin, tannin and rhamnolipids JBR 515 and 425, for the removal of cadmium, zinc and copper from activated sludge immobilized in 1.5% sodium alginate with 0.5% polyvinyl alcohol. We also established the impact of pH value on biosorbent regeneration with the analyzed biosurfactants and determined the critical micelle concentration (CMC) in solutions containing the biosorbent and biosurfactant and in exact samples with heavy metals. Saponin exhibited the highest effectiveness of metals leaching at pH 1-5, and rhamnosides at pH 5-6. In addition, the study demonstrated a signifi cant effect of the ratio of biosorbent mass to washing agent volume (m/V) on the effectiveness of metals leaching. Of the biosurfactants analyzed, saponin was ca. 100% effective in leaching zinc and copper. The effectiveness of the other biosurfactants was lower and depended on the metal being leached.

Advances and Outlook of Heavy Metal Treatment Technology from Municipal Solid Waste Incineration Fly Ash: A Review

“…In MEUF, surfactants are typically spiked into the wastewater at a concentration larger than their critical micelle concentration (CMC), and the surfactant monomers aggregate to form micelles. Surfactants, known as saponins, are a wide variety of natural nonionic biosurfactants that must be produced by many plants and microorganisms. − They have the benefits of biodegradability, low toxicity to nature, spontaneous generation capacity and flexibility of repeated use . To date, leaching studies of toxic heavy metals using green natural surfactants have only yielded limited results. − …”

“…Surfactants, known as saponins, are a wide variety of natural nonionic biosurfactants that must be produced by many plants and microorganisms. − They have the benefits of biodegradability, low toxicity to nature, spontaneous generation capacity and flexibility of repeated use . To date, leaching studies of toxic heavy metals using green natural surfactants have only yielded limited results. − …”