Comparative study of natural and modified biomass of Sargassum sp. for removal of Cd2+ and Zn2+ from wastewater

Abstract

Natural as well as acid modified dead biomass of brown marine alga Sargassum sp. was employed for the elimination of cadmium and zinc ions from synthetic wastewater; batch mode experiments were carried out to optimize various factors like adsorbent dosage, contact time, pH, agitation speed and primary metal ions concentration at room temperature (298.15 K) for both types of adsorbents i.e. natural and acid treated. Application of Langmuir and Freundlich isotherms suggested that the modified biomass adsorbed better as compared to the natural one; though sorption on the natural biomass was a physical process while that on the modified one was a physico-chemical process and thus was relatively difficult. The quantity of cadmium ions adsorbed was greater than that of zinc ions. Adsorption equilibrium for the metal ions sorption on treated Sargassum sp. biomass was established within 60 min for both cadmium and zinc ions with 95.3 and 90.1% removal efficiencies, respectively, but it was greatly influenced by the pH of the solution. The optimal conditions in the batch experiments were as follows: cadmium ions were removed effectively using 0.5 g of adsorbent and 5 mg/L initial metal ions concentration at pH 4 and 150 rpm agitation speed whereas the best results for zinc ions were obtained with 1 g of adsorbent and 5 mg/L initial metal ions concentration at pH 3 and 200 rpm agitation speed. The experimental data fitted well to the pseudo first order model as the values of metal uptake capacities were in good agreement with the experimental values. Thermodynamic studies show that the process is spontaneous and endothermic in nature. Desorption and regeneration studies reveal that recovery of biosorbent is low.

Adsorptive Removal of Cd(II) Ions from Wastewater Using Maleic Anhydride Nanocellulose

“…For both sorbents, the maximum Cd(II) ion %R capability was obtained at the optimum agitation speed of 250 rpm. is result was in agreement with the study reported by Mahmood et al [58]. Generally, an increase in the speed of agitation speed resulted in outstanding pollutant uptake capabilities and the agitation helps in overcoming the resistance of external mass transfer.…”

Massive Influx of Pelagic Sargassum spp. on the Coasts of the Mexican Caribbean 2014–2020: Challenges and Opportunities

“…Dead algal mass is reported to be more promising than living algae because it has a high metal ion sorption capacity at a high rate, and the adsorbed heavy metal ions present can easily be removed using de-ionized water or desorption agents [106]. There are several works on the use of many species of sargasso as biosorbents, and in the removal of pollutants, such as metal ions (e.g., Hg, Pb, Cu, Cd, Ni, Zn, Fe, and Cr), organic solvents, and organic dyes [107][108][109][110][111][112][113][114][115].…”

The Studies on Water Quality for Cobalt and Manganese Content in Drinking Water of Multan Area, Southern Punjab, Pakistan

“…Different processes are being used throughout the world for the removal of heavy and toxic metals from polluted water to make it drinkable. These processes include solvent extraction, membrane separation, micro & ultrafiltration, forward and reverse osmosis, coagulation, electrolysis, precipitation, phytoremediation, ion exchange and adsorption [22,23]. The adsorption of Co and Mn on low cost media such as alumina or bentonite seems to be an economically viable solution to make the polluted water of the Multan city areas as drinkable [24,25].…”