Adsorption characteristics of Cu2+ and Zn2+ from aqueous solution using carbonized food waste

Abstract

The aim of the present study was to analytically provide adsorption characteristics of Cu 2+ and Zn 2+ using carbonized food waste (CFW); more specifi cally, batch tests were conducted using various concentrations of metal ions, contact times, and initial pH levels in an attempt to understand the adsorption removal of heavy metal ions in aqueous solution at concentrations ranging between 50 and 800 mg/l. The results confi rmed that the adsorption equilibrium was established within a maximum of 80 min, and the maximum concentrations for adsorption of Cu 2+ and Zn 2+ were 28.3 and 23.5 mg/g, respectively. These adsorption levels indicate that CFW has better performance than many other adsorbents. In experiments using different pH conditions, the applicability to acid wastewater was found to be high, and an excellent adsorption removal ratio of 75%-90% was observed under acid conditions at pH 2-4. Furthermore, as the adsorption time increased, the calcium component in the CFW began to leach into the aqueous solution and raise the pH, accordingly causing the removal of heavy metal ions partially as a result of precipitation. When our results were analyzed using the Langmuir model and the Freundlich model for isothermal adsorptivity, the activity of CFW in this study was shown to be more consistent with the former; the adsorption speed of Cu 2+ and Zn 2+ according to a pseudosecond-order reaction model was found to be very fast for an initial concentration of not more than 100 mg/l. In a test in which an attempt was made to compare adsorption capacity values obtained from the experiments in this study with the aforementioned three models, the pseudosecond-order reaction model was found to provide results closest to the actual values.

Use of Modified Diethylamine Phosphorus-containing Polymer for Solid Phase Extraction of Cobalt and Lead in Fruit Samples Employing Flame Atomic Absorption Spectrometry

“…Matrix effects are the main problem in the atomic absorption spectrometry determination of metals in highly saline samples (31)(32)(33)(34)(35)(36)(37). The effect of some cations, anions, and some IA and IIA group metals on the recovery of the analytes was investigated using model solutions containing 20 µg lead and 10 µg cobalt and each foreign ion separately.…”

Recycling Possibility of the Salty Food Waste by Pyrolysis and Water Scrubbing

“…Li et al [14] showed that the greatest amount of energy was produced at 250 • C, although a change in carbon content was not significant through the characteristic food waste carbonization products using hydrothermal carbonization at 225 • C, 250 • C, and 275 • C. Parshetti [15] and Han et al [16] presented a possibility to treat contaminated water with carbonized food waste using the fact that char has an adsorption ability according to the carbonization temperature. Ahmed and Gupta [17] carried out the study regarding syngas, hydrogen gas, and energy recovery through food waste pyrolysis and gasification at the high temperature of 800~900 • C and Liu, Haili, et al [18] studied the effects of chloride salts contained in food waste on the production of bio-oil and gas through pyrolysis using microwave.…”

Adsorption of Zn(II) from Aqueous Solutions by Thiol-Functionalized MCM-48

“…Consequently, the removal of Zn(II) from wastewaters is important. Some methods are used to remove Zn(II) from wastewater, such as ion-exchange [1], precipitation [2], adsorption [3][4][5][6][7], membrane filtration [8] and solvent extraction [9,10]. Adsorption process is a simple and rapid method for removal of metal ions.…”