Chitosan-Hydroxyapatite Bio-Based Composite in Film Form: Synthesis and Application in Wastewater

Abstract

Water purification from toxic metals was the main objective of this work. A composite in film form was prepared from the biomaterials hydroxyapatite, chitosan and glycerol using the dissolution/recrystallization method. A nanoparticle-based film with a homogenous and smooth surface was produced. The results of total reflectance infrared spectroscopy (ATR-FTIR) and thermal gravimetric analysis (TGA/DTA) demonstrated the presence of a substantial physical force between composite components. The composite was tested for its ability to absorb Cd2+ and Zn2+ ions from aqueous solutions. Cd2+ and Zn2+ adsorption mechanisms are fit using the Langmuir model and the pseudo-second-order model. Thermodynamic parameters indicated that Cd2+ and Zn2+ ion adsorption onto the composite surface is spontaneous and preferred at neutral pH and temperatures somewhat higher than room temperature. The adsorption studies showed that the maximum adsorption capacity of the HAp/CTs bio-composite membrane for Cd2+ and Zn2+ ions was in the order of cadmium (120 mg/g) > Zinc (90 mg/g) at an equilibrium time of 20 min and a temperature of 25 °C. The results obtained on the physico-chemical properties of nanocomposite membranes and their sorption capacities offer promising potential for industrial and biological activities.

Fabrication of Polystyrene/AlOOH Hybrid Material for Pb(II) Decontamination from Wastewater: Isotherm, Kinetic, and Thermodynamic Studies

“…The pseudo-second-order model was best suited to the Pb(II) adsorption data, indicating that the Pb(II) adsorption rate-limiting step is chemisorption via the exchange or/and sharing of the electrons between the metal ions and PS/AlOOH, surface chelation, or ion-exchange. Similar Pb(II) adsorption behavior was also reported on allophane [26] and polystyrene microplastics adsorbent [18].…”

“…The results in Figure 7 show that the adsorption of Pb(II) onto PS/AlOOH was fast during the initial few minutes due to the empty adsorption sites on the hybrid polymer. The active sites become occupied with the Pb(II) ions as the interaction time increases, and the complete saturation of PS/AlOOH active sites occurred in 90 min, indicating the equilibrium establishment and that no place would remain vacant on the PS/AlOOH [26].…”

Design of Nanohydroxyapatite/Pectin Composite from Opuntia Ficus-Indica Cladodes for the Management of Microbial Infections

“…It is also used in the food industry as a thickener, gelling agent, emulsifier, and stabilizer. It is mainly used in fruit juices, jellies, and jams, in cooking fruit preparations, fruit drink concentrates, desserts, dairy products, and delicatessen products [ 8 , 9 ].…”

“…In addition, a recent publication showed that pectin extracted from banana peels can be used as a mediator in the preparation of Hydroxyapatite (HAp) [Ca 10 (PO 4 ) 6 (OH) 2 ] nanoparticles [ 14 ]. Pectin can be also used to synthetize copolymers based on chitosan and/or HAp [ 8 ].…”