Potential Use of Biochar from Various Waste Biomass as Biosorbent in Co(II) Removal Processes

Abstract

The removal of Co(II) ions from aqueous media was done using three types of biochars obtained from algae waste biomass, mustard waste biomass, and soy waste biomass. The biochar samples were obtained by pyrolysis of waste biomass resulted from biofules production, at relative low temperature (600–650 °C), and this procedure can be considered a suitable alternative to reduce the volume of such waste. FTIR spectra recorded for each type of biochar reveal the presence of several functional groups that can be used as binding sites for Co(II) retention. The batch biosorption experiments were performed as a function of initial Co(II) ions concentration and contact time, at constant solution pH (5.0), sorbent dose (8.0 g/L), and room temperature (25 ± 1 °C). The sorption experiments showed that the Co(II) ions retention reaches the equilibrium in maximum 60 min, and the maximum sorption capacity follows the order: Mustard biochar (MBC—24.21 mg/g) < soy biochar (SBC—19.61 mg/g) < algae biochar (ABC—11.90 mg/g). The modeling of experimental data proves that the retention of Co(II) ions from aqueous solution occurs through electrostatic interactions, and that the sorption process takes place until a monolayer coverage is formed on the outer surface of the biochar. This information is very useful in the design of a suitable desorption system. The desorption results showed that by treating the biochar samples loaded with Co(II) ions with 0.1 mol/L HNO3 solution, over 92% of Co(II) ions are desorbed and can be recovered, and the biochar samples can be used in at least three sorption/desorption cycles. All the experimental observations sustain the potential use of biochar obtained from different types of waste biomass as a promising alternative sorbent for the removal of Co(II) ions from aqueous media.

Biochars obtained from freshwater biomass—green macroalga and hornwort as Cr(III) ions sorbents

“…5, the sorption appeared to be fast and after about 60 min for hornwort and 120 min for macroalga biochars, the equilibrium was achieved. A rapid sorption at the beginning of the process and rather short time to equilibrium was also observed in our recent work (about 80 min) in sorption of Cr(III) ions [21] and by Lucaci et al (about 60 min) in sorption of Co(II) ions [22]. This phenomenon was also widely observed in numerous researches dealing with metal sorption onto biochar or activated carbons and might be a result of rapid occupation of the external surface sorption sites, easily available over biochar surface.…”

“…In agreement with the principles of sustainable development, it is important to use waste as a raw material for other processes [20]. Biochars produced from aquatic biomass are mainly used for the removal of toxic metal ions from wastewater [21,22] or as a soil amendment [23,24]. Biochar from freshwater macroalga-Cladophora glomerata was examined as a sorbent of Cr(III) ions [21]; biochar from post-extraction of macroalga residues after oil extraction was used for sorption of Co(II) ions [22]; biochar from water hyacinth was investigated as a sorbent of Zn(II) and Cu(II) ions [25]; biochar from waste marine seaweeds-kelp and hijiki-was applied for sorption of Cd(II), Cu(II), and Zn(II) ions [26].…”

Removal Efficiencies of Manganese and Iron Using Pristine and Phosphoric Acid Pre-Treated Biochars Made from Banana Peels

“…Despite this advantage, the use of the activated carbon adsorption process for the removal of heavy metals has been limited as it requires high maintenance and operational costs [14]. In recent years, biochars, which can be produced at low cost, have attracted great attention as an alternative to activated carbon [15][16][17][18]. Biochar is an ecofriendly adsorbent produced using by-products of the agricultural industries and wastes from various crops, and is effective for removing heavy metals from wastewater [18][19][20][21].…”

“…Raw biochars have showed feasibility for adsorbent material to remove contaminants including heavy metals and organic pollutants [17,18,21,27,28]. However, the sorption capacities can be enhanced by treatment with acids, nanocomposites, and activation agents [17,29,30].…”

Modeling and Optimizing of NH4+ Removal from Stormwater by Coal-Based Granular Activated Carbon Using RSM and ANN Coupled with GA

“…The Langmuir isotherm model assumes the number of active sites distributed homogeneously on the surface of the adsorbent followed by monolayer adsorption (physical adsorption) having high adsorptive power [37]. This suggested that the adsorption of NH 4 + takes place on the surface of the CB-GAC until a monolayer coverage was formed, after which the driving force of the sorption process decreases drastically [38]. The Q max calculated from the Langmuir model was 0.2821 mg/g.…”