Removal of phosphate ions from wastewater by treated hydrogel based on chitosan

Abstract

C HITOSAN/ Gelatin/2-(Dimethylamino) ethyl methacrylate (Cs/Gltn/PDMAEMA) hydrogel was synthesized by gamma irradiation for the expulsion of phosphate ions from wastewater. Chemical adjustment of the hydrogel with thiourea was performed to introduce thiol groups Cs/Gltn/PDMAEMA-treated. Moreover trapping of SiO 2 into the hydrogel matrix to acquire Cs/Gltn/PDMAEMA/SiO 2 composite. It was found that the gelation increases with increasing PDMAEMA content in the hydrogel. The maximum gelation performed at an equal ratio of Cs/Gltn at a radiation dose of 15 kGy. The adsorption capacities of the prepared systems towards phosphate ions were investigated. It was obtained that the maximum removal is achieved at pH 6 through 180 min. However, the removal percent decreases with increasing phosphate ions concentration and temperature. The ability of the prepared adsorbents towards phosphate ions removal are ascending ordered in the sequence of Cs/Gltn/PDMAEMA hydrogel, Cs/Gltn/PDMAEMA-treated , and Cs/Gltn/PDMAEMA/SiO 2 composite. The pseudo secondorder equation fits well the adsorption kinetics. The adsorption isotherm follows the Freundlich model higher than the Langmuir model

From waste to waste: iron blast furnace slag for heavy metal ions removal from aqueous system

“…Intensifying the dose caused an upsurge of the removal efficiency while the adsorption capacity was increased up to 1.67 g L −1 , and then decreased. Each metal ion is subjected to a larger unit mass of the adsorbent, which has more adsorption sites which ready to attract this ion (Mahmoud et al 2019 ).…”

Exploitation of industrial solid wastes for preparing zeolite as a value-added product and its kinetics as adsorbent for heavy metal ions

“…Table 5 shows that the diffusion does not represent a limiting step in the processes on zeolite. On the other hand, the higher adsorption capacity confirming that zeolite contains mesopores, with a large number of active sites opened for the low volume cations (Mahmoud et al, 2019). However, the plot of t 0.5 against qt, does not fit with a straight line passing through the origin but also with poor linear regression coefficients (R 2 ) indicating inapplicability of the model and intra-particle diffusion was not only the rate-controlling step.…”

From Waste to Waste: Iron Blast Furnace Slag for Heavy Metal Ions Removal from Aqueous System

“…4 Intensifying the dose caused an upsurge of the removal e ciency while the adsorption capacity was increased up to 1.67 g L −1 , and then decreased. Each metal ion is subjected to a larger unit mass of the adsorbent, which has more adsorption sites which ready to attract this ion (Mahmoud et al 2019). Temkin, Langmuir, and Freundlich isotherms were employed to investigate the sorption practice.…”

“…At a higher initial concentration, the driving forces to conquer the mass transfer barrier for ions' emigration through the medium to the sorbent solid surface upsurges. Nevertheless, each unit weight of the sorbent is exposed to a greater amount of ions steadily loading the sites until fullness(Mahmoud et al 2019).…”