Gemini surfactant: A novel flotation collector for harvesting of microalgae by froth flotation

Abstract

Froth flotation has been proved to be a promising approach for commercial scale harvesting of microalgae. However, all the surfactants used in the microalgae flotation harvesting process are conventional monomeric surfactants contain a single similar hydrophobic group in the molecule, which results in a low harvesting efficiency. In this work, a novel Gemini surfactant, N,N'-bis(cetyldimethyl)-1,4-butane diammonium dibromide (BCBD) was prepared, and originally recommended as a collector for froth flotation harvesting of Chlorella vulgaris from culture medium. The performance of BCBD was compared with the results acquired using its conventional monomeric surfactant cetyl trimethyl ammonium bromide (CTAB). The bench-scale flotation results showed that BCBD had excellent collecting power for Chlorella vulgaris. Achieving the obviously superior flotation harvesting performance (flotation recovery increased by 21.4 % and enrichment ratio increased by 22.9), the dosage of Gemini type BCBD collector is five times less than that of monomeric CTAB collector.

Effect of Particle Size on the Rising Behavior of Particle-Laden Bubbles

“…Five sizes of spherical soda lime glass beads particles were supplied by SiLi Sigmund Lindner GmbH (Germany), with a mass density of 2.5 g/cm 3…”

Efficient Removal of Pb(II) from Aqueous Systems Using Spirulina-Based Biohybrid Magnetic Helical Microrobots

“…Currently, nanosized metal oxides have been developed as adsorbents for heavy metal removal, including nanoparticles of Fe 2 O 3 , Al 2 O 3 , ZnO, and MnO 2 . , Among them, MnO 2 nanoparticles stand out due to the large surface area with the merits of strong adsorptive capability, whereas it is indispensable to tackle with their severe agglomeration and hard separation from aqueous systems. − Besides, some research studies are focused on natural biological materials (e.g., bacteria, diatomite, and microalgae), which are emerged as promising adsorbents due to the low-cost and high-efficient features. − They have unique biological structures with plentiful active sites on the surface such as hydroxyl and carboxyl groups, and both living and dead ones exhibit certain adsorption validity. , However, the biological adsorption process is determined by the diffusive mass transport and the removal efficiency needs to be improved. Moreover, collection and reusability of the microorganisms are also limited for practical application . Hence, it is imperative to endow the microorganisms with additional delicate modification for versatile integration to achieve high-efficient adsorption toward heavy metal ions.…”

“…Moreover, collection and reusability of the microorganisms are also limited for practical application. 22 Hence, it is imperative to endow the microorganisms with additional delicate modification for versatile integration to achieve high-efficient adsorption toward heavy metal ions. Recent developments in micro-/nanorobots have provided possibilities to explore novel adsorbents to solve the above challenges.…”

Recycling Lepidolite from Tantalum–Niobium Mine Tailings by a Combined Magnetic–Flotation Process Using a Novel Gemini Surfactant: From Tailings Dams to the “Bling” Raw Material of Lithium

“…Gemini surfactants, which differ from traditional monomeric surfactants that have only one lipophilic tail and one lipophobic head group, are a novel series of surfactants that have two lipophilic chains and two lipophobic head groups chemically bonded together by the spacer. − In comparison with the corresponding traditional monomeric surfactant, a gemini surfactant possesses remarkable physicochemical properties, including lower Krafft point, excellent solubility, lower critical micelle concentration (cmc), − higher surface activities, better wetting, foaming, and lime-soap dispersing properties, higher thermal stability, and biological properties. , Due to the characteristic structure and outstanding activities, gemini surfactant has been extensively used for multiple applications such as conventional detergent, cosmetic, food industry, facile soft template, nonviral gene delivery vector, drug delivery agent, or antimicrobial. ,− …”