Removal of Heavy Metals (Cd2+, Cu2+, Ni2+, Pb2+) from Aqueous Solution Using Hizikia fusiformis as an Algae-Based Bioadsorbent

Abstract

This study investigated the applicability of algae (Hizikia fusiformis, Green gracilaria, and Codium fragile) for removing heavy metals (Cd2+, Cu2+, Ni2+, and Pb2+) from aqueous solutions. Among the algae, H. fusiformis was chosen as a bioadsorbent and modified with NaOH and HCl. The results showed that the biosorption capacity of H. fusiformis improved significantly after treatment with NaOH; however, H. fusiformis modified with HCl did not achieve the expected value. The NaOH treatment enhanced the biosorption of metals on the treated H. fusiformis because of the hydrolysis reaction producing carboxylic (–COOH) and hydroxyl groups (–OH). The kinetics for Cd2+, Cu2+, Ni2+, and Pb2+ biosorption well fitted to pseudo-first-order, pseudo-second-order, and Elovich models, with R2 of >0.994. The Freundlich model provided a good fit for the equilibrium biosorption of Cd2+, Cu2+, and Ni2+ by both algae and the Langmuir model for Pb2+. The maximum biosorption of metals was in the order Pb2+ >> Cu2+ ≈ Ni2+ > Cd2+, with qmax of 167.73, 45.09, 44.38, and 42.08 mg/g, respectively. With an increase in the solution pH, metal biosorption was enhanced, and considerable enhancement was observed in the pH range of 2–4. Thus, H. fusiformis is expected to be considered a superior candidate for metal biosorption.

Hierarchically 3-D Porous Structure of Silk Fibroin-Based Biocomposite Adsorbent for Water Pollutant Removal

“…A further comparison of adsorption capacity with other classes of adsorbent was carried out as follows: The present results of SF:SS (4:1) show better CV adsorption capacity of 83.31 mg•g −1 (according to the Langmuir adsorption isotherm) compared to the biochar derived from palm-kernel shell [55]. For Cu 2+ adsorption, the SF:SS biocomposite adsorbent exhibits better adsorption capacity, of up to 73.22 mg•g −1 , than that of algae-based bioadsorbent, which showed an adsorption capacity of 42.25 mg•g −1 [56]. This maximum Cu 2+ adsorption capacity is, however, comparably lower than that of diethylenetriaminemodified polyacrilonitrile (DETA-PAN) fibers, which shows a maximum Cu 2+ adsorption capacity up to 112.3 mg•g −1 [57].…”

Efficacious bioremediation of heavy metals and radionuclides from wastewater employing aquatic macro‐ and microphytes

“…Among these groups, different aquatic plants species, such as Spirodela intermedia, Myriophyllum aquaticum, Mentha aquatic, Ludwigina palustris have been extensively used for the removal of heavy metals and radioactive compounds from wastewater [21]. Additionally, different aquatic weeds, like Lemna minor and other water hyacinths like Pontederia crassipes, Pistia stratiotespito, water spinach Ipomoea aquatic, and water lettuce are also proficient in accumulating the carcinogenic and mutagenic contaminants from wastewater [18,22]. Thus, aquatic micro-and macrophytes possesses the potential to sequestrate carbon from atmosphere offering simultaneous holistic treatment to the wastewater.…”

“…Recently, Pham et al [22] cultured three types of marine algae namely, Hizikia fusiformis, Green gracilaria, and Codium fragile for the removal of carcinogenic heavy metals such as Cu 2+ , Ni 2+ , Cd 2+ , and Pb 2+ from synthetic wastewater. However, green algae H. fusiformis was selected as superior candidate among other algae due to its better heavy metal bio-adsorbing capacity.…”

“…However, green algae H. fusiformis was selected as superior candidate among other algae due to its better heavy metal bio-adsorbing capacity. Under the alkaline condition (pH ranging from 2 to 4) at 25°C, the maximum metal biosorption capacity of brown algae H. fusiformis was 167.73, 45.09, 44.38, and 42.08 mg/g in the order of Pb 2+ ≫ Cu 2+ ≈ Ni 2+ > Cd 2+ , respectively, with initial metal concentration of 100 mg/L [22]. Moreover, Cd 2+ , Cu 2+ , Ni 2+ , and Pb 2+ removal efficiency of 14.9%, 31.6%, 10.9%, and 10.9% was achieved by utilizing H. fusiformis, respectively [22].…”

“…Under the alkaline condition (pH ranging from 2 to 4) at 25°C, the maximum metal biosorption capacity of brown algae H. fusiformis was 167.73, 45.09, 44.38, and 42.08 mg/g in the order of Pb 2+ ≫ Cu 2+ ≈ Ni 2+ > Cd 2+ , respectively, with initial metal concentration of 100 mg/L [22]. Moreover, Cd 2+ , Cu 2+ , Ni 2+ , and Pb 2+ removal efficiency of 14.9%, 31.6%, 10.9%, and 10.9% was achieved by utilizing H. fusiformis, respectively [22]. In another investigation, two indigenous algal species Zygogonium ericetorum and Oscillatoria tenuis removed maximum of 99.40, 84 µg of Ni, and 66.84, 64.83 µg of Cr and 451, 441 µg of Pb, respectively [87].…”