An overview of heavy metal removal from wastewater using magnetotactic bacteria

Abstract

Considering the increase in water contamination by heavy metal discharge, water quality experts are focusing on innovative future technologies for wastewater treatment. There are a number of physical, chemical and biological processes for acquiring high‐quality effluents; however, these treatment technologies have shown some limitations regarding their specific pollutant removal efficiencies, vulnerability to environmental pollutants, higher cost and energy requirements, excessive sludge volume and toxicity issues. Therefore, this review/concept paper focuses on the application of magnetotactic bacteria (MTB) in the removal of heavy metal from wastewater and also proposes a model application of MTB‐based treatment process. The unique property of the MTB is to move along the periphery of the applied external magnetic fields due to nano sized magnetosomes (MS). MS are basically the biomineral crystals of either magnetite (Fe3O4) or greigite (Fe3S4) with a size range of 30–120 nm. Moreover, challenging aspects concerning MTB employment in the removal of heavy metal from wastewater also are discussed in detail for the consideration of experts who are involved in the development of new treatment technologies or for retrofications of existing processes. © 2018 Society of Chemical Industry

Development and application of novel bio-magnetic membrane capsules for the removal of the cationic dye malachite green in wastewater treatment

“…15,16 Among them, adsorption is considered comparatively superior in terms of high efficiency, low cost, easy installation and easy operation over other technologies. [17][18][19][20] In the past, a variety of adsorbents have been utilized to remove different kinds of toxic dyes, including agricultural waste material (rice husk, pinewood, orange peel, peanut hull, banana pith and jute ber), red mud, cellulose, zeolite, ion-exchange resins, activated carbon, clay, chitosan, graphene oxide (GO) and its composites/ derivatives, and so forth. 21 However, some specic issues (low kinetics, poor stability, low removal performance, nonenvironmental friendliness and lack of reusability) are hampering its employment for commercial applications.…”

“…Mostly green magnetic nanoparticles (MNPs) have been utilized at lab-scale to remove toxic dyes and metal ions from wastewater. [17][18][19][20] However, MNPs are showing low removal performance, low adsorptive capacity and poor stability for long-term applications due to their oxidation in water treatment. Thus, these disadvantages have hampered the transfer of green nanotechnology from the lab-scale to the commercial scale and various kinds of coating technologies have been used to improve the stability, but they could not enhance the adsorptive capacity.…”

Applications of Magnetotactic Bacteria, Magnetosomes and Magnetosome Crystals in Biotechnology and Nanotechnology: Mini-Review

“…The incorporation of another transition metal in magnetosome magnetite modified the magnetic properties of the crystals and could therefore lead to the design of new biomaterials with specific, possibly tailor-made magnetic properties. Based on the absorption and immobilization of metals from culture medium and the fact that MTB can be magnetically removed from sediment and water, the use of these microorganisms in bioremediation has been proposed by several investigators [ 84 , 85 , 86 , 87 ]. Tanaka and colleagues [ 84 ] showed that cells of Ms. magneticum AMB-1 are relatively resistant to tellurium and able to concentrate and crystallize this element in structures different from magnetosomes within the cell.…”

Multi-metal resistance and potential of Alcaligenes sp. MMA for the removal of heavy metals

“…For the desorption of Pb 2+, HNO 3 was used with 98% recovery, and Na 3 PO 4 was used as a most efficient precipitant [39]. Ali et al [4], reviewed the magnetotactic bacteria efficiency to bind metals. The nanosized magnetosomes (magnetite crystals) aids in biosorption by providing them with the ability to move along the externally applied magnetic field.…”