Use of Chemically Treated Human Hair Wastes for the Removal of Heavy Metal Ions from Water

Abstract

Human hair is considered a ubiquitous waste product and its accumulation can cause environmental problems. Hence, the search for alternatives that take advantage of this waste as a new raw material is of interest, and contributes to the idea of the circular economy. In this study, chemically modified human hair was used as a low cost biosorbent for the removal of heavy metal ions from aqueous solutions. The effect of the contact time, the pH, and the biosorbent concentration on the biosorption process were investigated. Kinetic modeling indicated that the pseudo-second order kinetic equation fitted well with R2 > 0.999. Furthermore, the equilibrium data fitted the Langmuir adsorption isotherm at 295 K resulting in saturation concentrations of 9.47 × 10−5, 5.57 × 10−5, 3.77 × 10−5, and 3.61 × 10−5 mol/g for the sorption of Cr(III), Cu(II), Cd(II), and Pb(II), respectively. The biosorption process did not change the chemical structure and morphology of the hair, which was shown by FTIR and SEM. In addition, desorption experiments prove that 0.1 mol/L EDTA solution is an efficient eluent for the recovery of Pb(II) from the treated human hair. To summarize, treated human hair showed satisfactory biosorption capacity and can be considered as an effective biosorbent for the treatment of water with a low concentration of heavy metal ions.

Synthesis and Characterization of Rice Husk Biochar and its Application in the Adsorption Studies of Lead and Copper

“…According to regression coefficient (R 2 ) as shown in Tables 3 and 4 the Pseudo-first order did not provide a good description of the sorption process of the Pb 2+ and Cu 2+ they were very low that is 0.0040 and 0.3977 respectively. The same results corresponded to [15] in the removal of heavy metal ions by use of treated human hair.…”

“…The Pseudo-second order model predicts that the process of heavy metal adsorption involves the exchange of electrons between the metal ions and the adsorbent and consequently leading to the formation of a chemical bond [15]. The linearized form of Pseudo-second order kinetics is;…”

Turning Food Protein Waste into Sustainable Technologies

“…For instance, wool keratin has more sites for disulfide bonds and higher molecular weights than feather keratin, making it a superior adsorbent for heavy metals removal from water . Moreover, keratinous-composed fibers can be chemically modified to improve removal performance …”

“…614 Moreover, keratinous-composed fibers can be chemically modified to improve removal performance. 615 In all of these reports, the waste was used directly for water purification, and as it can contain other compounds, such as polysaccharides, and the prominent role of proteins cannot be unambiguously acknowledged. 616 Furthermore, the significant difference between the purification performance of pure proteins and waste may suggest the inaccessibility of proteinbinding sites in the waste to water pollutants.…”

Valorization of food industrial waste into protein amyloid fibrils for water and energy applications

“…Gelatin, with its good gelation properties, has also been fabricated into hydrogel nanocomposites with iron nanoparticles or chitosan for water purification from lead and cadmium [210][211][212]. Keratin extracted from chicken feathers and human hair have proved to be excellent heavy metal adsorbents due to their rich thiol composition [213][214][215][216], while the addition of collagen obtained from leather processing scraps with alginate and alumina improved metal adsorption capacities [217].…”