Alkaline-treated sawdust as an effective material for cationic dye removal from textile effluents under dynamic conditions: breakthrough curve prediction and mechanism exploration

Abstract

This paper deals with the methylene blue molecule (MB) removal from synthetic and real textile wastewaters by alkali-treated orange tree sawdust (ATOS) under different dynamic conditions. Experimental results showed that MB removal efficiencies by ATOS increased when increasing initial dye concentrations and bed depths but decreased with the increase of the applied flow rates with a maximum adsorption capacity of about 110 mg g. Moreover, various empirical models were applied to predict the experimental breakthrough curves (BTCs) and to determine the characteristic adsorption parameters. The applied models successfully fitted data in the following order: Thomas ([Formula: see text] = 0.969), dose response ([Formula: see text] = 0.949), and Clark ([Formula: see text] = 0.874). ATOS was also found to efficiently remove dyes and other mineral pollutants such as chlorides, nitrates, and phosphates from real wastewaters. MB removal by ATOS involved not only cationic exchange but also complexation with acidic and basic functional groups. Moreover, important MB desorption yields from ATOS (more than 93%) were obtained when using saline solutions. All these results confirmed that NaOH-treated orange tree sawdust can be considered as a promising material for the removal of cationic dyes from industrial wastewaters.

Preparation and characterization of chitosan extracted from shrimp shells waste and chitosan film: application for Eriochrome black T removal from aqueous solutions

“…Adsorption onto low-cost materials has pointed out as one of the most effective methods for dye removal especially for low concentrated effluents (Bharathi and Ramesh 2013). Various materials have been successfully used for dye removal in static and/or dynamic mode such as orange tree sawdust (Azzaz et al 2017), cellulose-based bioadsorbent (Liu et al 2015), different marine macroalgae (Omar et al 2018) and chitosan (Vega-Negron et al 2018).…”

Investigations on lignite use for lead removal from aqueous solutions under static and dynamic conditions: adsorption properties and mechanism exploration

“…The experimental adsorbed Pb(II) masses (M ads ) per gram of lignite (q sat ) during the column assays were determined through the trapezoidal rule approximation [16]:…”

“…However, the majority of these studies were performed in small-volume flasks (static conditions). The extrapolation of the obtained batch results to real cases is often very difficult to perform due to the complexity of the real wastewater composition and its important variation in time along with its flow rate [8,16]. Therefore, studying Pb(II) removal in continuous mode (i.e., laboratory columns or continuous stirring tank reactor) is closer to the reality and will have an important added value compared to the static assays.…”

Investigation of a hybrid material and photophysical properties of rhodamine B in aqueous suspensions of cellulosic particles

“…Basic Blue 41, thiacyanine and brilliant green, in aqueous suspensions. [5][6][7][8][9][10] Because of the penetration of dye molecules on the surface of any particle in a suspension, spectral shifts called H-or J-aggregation (molecular self-assembly) in their absorption spectra can be observed. 11 Generally, the aggregation behaviour of dye molecules takes place in the highly concentrated dye aqueous solution.…”