Syringa vulgaris leaves powder a novel low-cost adsorbent for methylene blue removal: isotherms, kinetics, thermodynamic and optimization by Taguchi method

Abstract

In this study, the potential of a new low-cost adsorbent, Syringa vulgaris leaves powder, for methylene blue adsorption from aqueous solution was investigated. The adsorbent surface was examined using SEM and FTIR techniques. The experiments were conducted, in batch system, to find out the effect of pH, contact time, adsorbent dose, initial dye concentration, temperature and ionic strength on dye adsorption. The process is best described by Langmuir isotherm and the pseudo second order kinetic model. Maximum adsorption capacity, 188.2 (mg g−1), is better than other similar adsorbent materials. Thermodynamic parameters revealed a spontaneous and endothermic process, suggesting a physisorption mechanism. A Taguchi orthogonal array (L27) experimental design was used to determine the optimum conditions for the removal of dye. Various desorbing agents were used to investigate the regeneration possibility of used adsorbent. Results suggest that the adsorbent material is very effective for removal of methylene blue from aqueous solutions.

Chemical Profile, Cytotoxic Activity and Oxidative Stress Reduction of Different Syringa vulgaris L. Extracts

“…Therefore, the peak occurring within range 1596–1608 cm −1 could be attributed to C=C stretching vibrations from the structure of both flavonols and iridoids [ 24 , 26 , 27 , 28 ]. Similarly, in the FT-IR spectra of S. vulgaris analyzed extracts, flavonols possess C–O–C, C=C and CH 3 functional groups which display peaks between 924–930 cm −1 , 1159–1162 cm −1 and 1385–1404 cm −1 respectively [ 20 , 23 , 27 , 28 , 29 ] ( Table 2 and Table 3 ).…”

“…Infrared spectroscopy is an effective and non-targeted analytical method which could non-destructively and cost-effectively detect the intrinsic quality of different plants [ 19 , 20 ]. Based on FT-IR results, it is possible to highlight a list of peaks that can be assigned to different biochemical class of compounds, which could lead to a better correlation between the chemical structure and the spectroscopic features of plants [ 21 ].…”

“…Based on FT-IR results, it is possible to highlight a list of peaks that can be assigned to different biochemical class of compounds, which could lead to a better correlation between the chemical structure and the spectroscopic features of plants [ 21 ]. Therefore, this technique also provides a precise assignment of the functional groups, bonding types and molecular conformations within plant tissue and cells [ 20 ].…”

“…Within a similar range, terpene-associated stretching vibrations of C=O had contribution to band from 1694–1702 cm −1 [ 23 ]. Another terpene-associated peak was observed in the range 2901–2909 cm −1 and was caused by the C–H stretching vibration [ 20 , 23 , 24 , 25 ]. Furthermore, the peaks found between 885–890 cm −1 and 2925–2933 cm −1 were associated with the presence of CH 2 functional group, while the peak between 1256–1268 cm −1 could be attributed to C–O stretching vibration from both terpene and iridoids [ 23 ].…”

Sanky (Corryocactus brevistylus) Peel as Low-Cost Adsorbent for Removal of Phosphate from Aqueous Solutions

“…The prices of the chemical reagents were obtained from the corresponding vendors. Some authors reported that adsorbents are usually inexpensive provided they are prepared from natural materials available in large quantities, require little processing, or are a byproduct or agricultural waste [47][48][49]. Most studies do not provide information on manufacturing costs.…”