POLYMER COMPOSITE MATERIAL BASED ON POLYURETHANE AND CHITIN - THE SORBENT OF HEAVY METAL IONS
This study provides information on the рolymer composite material (PCM) based on the elastic polyurethane foam and chitin (PPU10X). The presence of chitin in the structure PCM, characteriing as the effective material for the sorption of metal ions, makes it possible to assume that the combined material will also have the same property. The sorption capacity of ions Cr<sup>6+</sup>, Pb<sup>2+</sup>, Cu<sup>2+</sup> and Zn<sup>2+</sup> is estimated. The effect of the initial concentration of ions in the solution is studied. It is discussed about the information of sorbate distribution on the surface of the research sorbent through evaluation of isotherm models Langmuir, Freundlich, Temkin and Dubinin-Radushkevich. The possible mechanism for heavy metal ion sorption on the surface material PPU10X is also proposed in this paper. The results show that the sorption of ions Cr<sup>6+</sup> is observed to be the best, while Cu<sup>2+</sup> ion sorption is observed the lowest. The sorption of ions Zn<sup>2+</sup>and Cr<sup>6+</sup> fit well with the isotherm model Langmuir. Meanwhile, the sorption of ions Pb<sup>2+</sup> and Cu<sup>2+</sup> fit well with the Freundlich isotherm model. The highest sorption capacity according to the Langmuir isotherm model reach 14,641 mg/g (for Zn<sup>2+</sup>) and 32,258 mg/g (for Cr<sup>6+</sup>), 14,62 mg/g (for Pb<sup>2+</sup>), and 6,653 mg/g (for Cu<sup>2+</sup>), respectively. The proposed sorption mechanism is mainly based on complexion, electrostatic interaction, chelating of metal ions with functional groups present in the structure of the material. Thus, it can be seen that PPU10X can be used as a sorbent to cleaning wastewater containing heavy metal ions. Besides, this potential material is simple and easy to use in the wastewater treatment technology.