Influence of Wooden Sawdust Treatments on Cu(II) and Zn(II) Removal from Water

Abstract

Organic waste materials and semi-products containing cellulose are used as low-cost adsorbents that are able to compete with conventional sorbents. In addition, their capacity to bind heavy metal ions can be intensified by chemical treatments using mineral and organic acids, bases, oxidizing agents, and organic compounds. In this paper, we studied the biosorption capacity of natural and modified wooden sawdust of poplar, cherry, spruce, and hornbeam in order to remove heavy metals from acidic model solutions. The Fourier transform infrared spectroscopy (FTIR) spectra showed changes of the functional groups due to the alkaline modification of sawdust, which manifested in the considerably increased intensity of the hydroxyl peaks. The adsorption isotherm models clearly indicated that the adsorptive behavior of metal ions in treated sawdust satisfied not only the Langmuir model, but also the Freundlich model. The adsorption data obtained for studied sorbents were better fitted by the Langmuir isotherm model for both metals, except for spruce sawdust. Surface complexation and ion exchange are the major mechanisms involved in metal ion removal. We investigated the efficiency of the alkaline modified sawdust for metal removal under various initial concentrations of Cu(II) and Zn(II) from model solutions. The highest adsorption efficiency values (copper 94.3% at pH 6.8 and zinc 98.2% at pH 7.3) were obtained for poplar modified by KOH. For all types of sawdust, we found that the sorption efficiency of modified sorbents was higher in comparison to untreated sawdust. The value of the pH initially increased more in the case of modified sawdust (8.2 for zinc removal with spruce NaOH) and then slowly decreased (7.0 for Zn(II) with spruce NaOH).

Pb(II) Ion Removal Potential in Chemically Modified Ziziphus joazeiro Barks

“…Analyzing the FT-IR spectrum, the peak of 3360.04 cm −1 was shifted to 3401.63 cm −1 , with a significant increase in intensity and width after the alkaline treatment. These peaks are commonly associated with intra- and intermolecular -OH stretching vibration from cellulose, lignin and hemicellulose [ 81 ], in addition to saponins [ 82 ]; such behavior was also observed in the treatment performed by [ 12 , 83 ]. The 2933.33 cm −1 peak referring to the stretching of the C-H bonds of the hydrocarbons became more discreet, while those in the 1200 to 1500 cm −1 range showed a number of peaks and a reduction in width.…”

Thermal Properties of Wood Dust Fibre and Recycled Polypropylene (r-WoPPc) for Development of Thermoplastic Composites Filaments of Fused Deposition Modeling

“…The wood waste is turned into a powder with a portable grinder and then filtered using an industrial siever at the FTKMP composite lab at UTeM. The seiver mesh size utilized ranges from 300-micron meter through 200-micron meter to 125-micron meter, then the outcome of wood powder is a 125-micron meter mesh that is clean of harmful elements as Figure 1(a), portable grinder (Figure 1(b)), industrial siever (Figure 1(c)) [12].…”

Copper(II) ion removal by chemically and physically modified sawdust biochar

“…The modified SDA and SSD biochars were noticed to have improved sorptions for Cu(II) ions in comparison to SD biochar owing to the increased surface area and huge pore size leading to an increase in the available sorption sites for Cu(II) ion removal. Further biosorption investigations were undertaken at pH 5.5-6.0 [28,65,66].…”