Adsorption Studies of Pb(II) and Cd(II) Heavy Metal Ions from Aqueous Solutions Using a Magnetic Biochar Composite Material

Abstract

Heavy metal toxicity in water is a serious problem that may have harmful effects on human health and the ecosystem. Lead [Pb(II)] and cadmium [Cd(II)] are two such heavy metal ions, present in water, whose severity is well-known and well-studied. In the current research, magnetic biochar composite (MBC) is studied as an adsorbent material for the effective removal of lead and cadmium ions from water solutions. Magnetite (Fe3O4) nanoparticles and pine-needle-derived ultrasonicated magnetic biochar were used in different weight ratios to prepare APTES (3-aminopropyl triethoxysilane)-functionalized MBC (FMBC). An average crystalline size of ~10 nm for magnetite NPs was obtained via XRD analysis. The adsorption characteristics of both Pb(II) and Cd(II) ions were investigated in a batch experiment. The FTIR spectra of raw biochar, MBC, FMBC, and metal-loaded FMBC were obtained at different stages. The decrease in the intensity of the –NH2 functional group in the FTIR spectra of the residue confirmed the successful adsorption of heavy metal ions. The SEM-EDX spectra of the residue showed the uniform adsorption of Pb(II) and Cd(II) heavy metal ions onto the surface of the adsorbent. Magnetic biochar composite (MBC) was found to be a very effective adsorbent at basic pH, as a maximum of 97% instantaneous heavy metal removal was observed for both ions in synthetic water solutions. The Langmuir isotherm model predicted the monolayer adsorption and good affinity between the metal ions and adsorbent. The prepared MBC is low-cost, environmentally friendly, and it has shown good adsorption performance. Therefore, our study suggests that the magnetic biochar composite under study is an effective adsorbent for lead and cadmium metal ion removal from aqueous solutions at normal room temperature. Only a few hundred milligrams of the adsorbent dose is sufficient to remove higher concentrations (~100 ppm) of lead and cadmium at basic pH conditions of aqueous solutions.

Study of graphene incorporation into ZnO-PVA nanocomposites modified electrode for sensitive detection of cadmium

“…With the current rise in industrial activity, there is an accompanying increase in the discharge of industrial effluents containing various unknown inorganic contaminants. Among these contaminants are hazardous heavy metals, including copper (Cu) [ 1 ], mercury (Hg) [ 2 ], lead (Pb) [ 3 ], cadmium (Cd) [ 4 ], cobalt (Co) [ 5 ], arsenic (As) [ 6 ], and iron (Fe) [ 7 ]. Even at low concentrations, the heavy metals cause health risks when they accumulate in the human body, leading to issues such as anorexia, hepatitis, nephritis syndrome, kidney damage, insomnia, and cancer [ 8 ].…”

Composites Based on CaCl2-CaBr2 Salt System for Adsorption Applications: Designing the Optimal Sorbent for Gas Drying and Air Conditioning

“…Indeed, very often, composite materials demonstrate more impressive results than nonmodified traditional sorbents. The modified sorbents demonstrate affinity to both organic [12][13][14] and inorganic [15,16] compounds/pollutants. The composites materials "Salt inside a porous matrix" (CSPM) are characterised by a high sorption ability (0.4-1.4 g/g) caused by the reaction of salt confined into matrix pores with water, methanol or ammonia [17][18][19].…”