DOI: 10.5061/dryad.9w0vt4bs3
title: Data from: Sustainable wastewater decontamination of chlortetracycline using kaolin-alginates beads: Practical applications and adsorption mechanisms

description: This study systematically evaluates the adsorption performance of kaolin
 (KN), kaolin-alginate beads (KN@Alg), and activated carbon (AC) for
 chlortetracycline (CTC) removal from water. Comprehensive characterization
 using FT-IR, SEM-EDX, XRD, and XPS revealed that incorporating alginate
 into KN significantly enhanced its adsorption capacity by increasing
 binding sites. KN@Alg exhibited a superior adsorption capacity (68.74
 mg/g) compared to KN (42.76 mg/g), though slightly lower than AC (102.96
 mg/g). In terms of removal efficiency, KN@Alg (68.44%) and AC (79.45%)
 outperformed KN (55.04%). Kinetic studies indicated that CTC adsorption on
 KN and KN@Alg followed both pseudo-first-order and pseudo-second-order
 models, suggesting combined physisorption and chemisorption mechanisms,
 while AC adsorption was dominated by physisorption. Isotherm analysis
 showed that KN@Alg exhibited greater surface heterogeneity, with
 adsorption well-described by the Freundlich and Langmuir models, whereas
 KN and AC followed the Langmuir model. Thermodynamic analysis confirmed
 that CTC adsorption on KN@Alg was exothermic and spontaneous, with optimal
 performance at 298 K, while KN displayed limited capacity across
 temperatures. KN@Alg addressed key limitations of KN (recycling
 difficulties, particle aggregation) and pure alginate beads (instability,
 low reuse rates), while enhancing adsorption performance. Regeneration
 studies over four cycles demonstrated KN@Alg’s superior reusability
 compared to AC and KN. Dynamic studies using solid-phase extraction (SPE)
 cartridges and continuous bead columns achieved exceptional CTC removal
 rates of 93.8% and 93.7%, respectively, in river water samples containing
 5 mg/L CTC, showcasing KN@Alg’s practical applicability. XPS analysis
 revealed multiple adsorption mechanisms, including n-π interactions,
 hydrogen bonding, electrostatic, cation exchange, and cation-bridging
 interactions involving calcium-alginate groups and kaolin’s Si/Al
 components. These findings highlight KN@Alg as a cost-effective,
 sustainable alternative to AC for CTC removal in water treatment.
description: # Data from: Sustainable wastewater decontamination of chlortetracycline
 using kaolin-alginates beads: Practical applications and adsorption
 mechanisms
 [https://doi.org/10.5061/dryad.9w0vt4bs3](https://doi.org/10.5061/dryad.9w0vt4bs3) ## Description of the data and file structure The data presented here about the adsorption process of CTC and they were calculated from the Abs from UV Vis machine.  Characterization data were also provided here.  ### Files and variables #### File: characterization_data.xlsx **Description:**  ##### Variables * KN@Alg refer to alginate beads incorporated kaolin clay * CTC is the drug used in this study chlortetracylibe. * AC is ACTIVATED CARBON * mg/g UNIT oF ADSORPTION CAPACITY * mg/L unit of CTC concentration * ev is the binding energy unit means electron volt. **Description:**  The characterization data include XPS and EDS analyses of KN@Alg before and after CTC adsorption, in addition to XRD patterns of both KN and KN@Alg. Also included FT-IR spectra of KN, Alg@KN, and Alg@KN after CTC adsorption, as well as pH-dependent point of zero charge (PZC) measurements. **XPS data** Data of XPS survey and high-resolution Ca, Al, and Si spectra of KN@Alg before and after CTC adsorption. | **Column Name** | **Units** | **Description** | | :----------------- | :---------------------- | :----------------------------------------------------------------------------------------- | | **Binding energy** | electron volt (eV) | The energy required to excite an inner-shell electron of an atom to the vacuum level. | | **Intensity** | counts per second (cps) | The number of photoelectron signals received by the detector at a specific binding energy. | **EDS data** Changes in the elemental composition (by weight) of KN@Alg beads before and after CTC adsorption. | **Column Name** | **Units** | **Description** | | :-------------- | :---------- | :-------------------------------------------------------------------------------------------- | | **Element** | (unitless) | The elements of KN\@Alg beads before and after CTC adsorption. | | **Weight** | percent (%) | The weight percentages of elemental content in KN\@Alg beads before and after CTC adsorption. | **XRD data** XRD data of both KN and KN@Alg. | **Column Name** | **Units** | **Description** | | :-------------- | :--------------------- | :-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **theta  2θ** | Degree (°) | The diffraction angle (2θ), which is the angle between the incident X-ray beam and the diffracted beam received by the detector of the diffractometer. It is twice the Bragg angle (θ). | | **Intensity** | Arbitrary units (a.u.) | The diffraction intensity, which is the number of X-ray photon signals received by the detector at a specific diffraction angle (2θ). | **FTIR** The FT-IR spectra describe samples of KN, Alg@KN, and Alg@KN after CTC adsorption. | **Column Name** | **Units** | **Description** | | :---------------- | :---------------------------- | :---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **Wavenumber** | reciprocal centimeters (cm⁻¹) | Wavenumber is proportional to the energy and frequency of the infrared light absorbed by the sample. It directly corresponds to the vibrational energy levels of specific chemical bonds. | | **Transmittance** | percent (%) | This axis shows how much infrared light is absorbed or transmitted by the sample at each wavenumber. | **pH~PZC~** This dataset contains pH measurements from pH drift experiments conducted to characterize the surface charge properties of three materials: KN, KN@Alg, and AC. The initial pH (pHinitial) was adjusted using HCl or NaOH, and the corresponding final pH (pH~final~) values were recorded after 24 hours of equilibrium. The difference (ΔpH = pH~final~ − pH~initial~) was used to determine the point of zero charge (PZC) for each material by identifying the x-intercept (where ΔpH = 0) of the ΔpH vs. pHinitial plot. The data demonstrate the buffering capacity and pH-dependent surface reactivity of each adsorbent. | **Column Name** | **Units** | **Description** | | :----------------- | :--------- | :--------------------------------------------------------------------- | | pH initial | (unitless) | The initial pH (pH~initial~) of three (KN, KN\@Alg, and AC) materials. | | pH final (KN) | (unitless) | After 24 h of equilibrium, The final pH (pH~final~) of KN. | | pH final (KN\@Alg) | (unitless) | After 24 h of equilibrium, the final pH (pH~final~) of KN\@Alg. | | pH final (AC) | (unitless) | After 24 h of equilibrium, the final pH (pH~final~) of AC. | #### File:experiment_data.xlsx **Description:**  **The effect of CTC concentration** This dataset contains experimental results from batch adsorption studies investigating the removal of CTC from an aqueous solution. The data represents the equilibrium adsorption capacity of three different adsorbents at varying initial CTC concentrations. The CSV file contains the following columns: | **Column Name** | **Units** | **Description** | | :-------------- | :-------------------------- | :--------------------------------------------------------------------------------------------------------------------------------- | | **C** | milligrams per liter (mg/L) | The initial concentration of the CTC in the solution before adsorption has occurred. | | **Qe\_KN** | milligrams per gram (mg/g) | The equilibrium adsorption capacity of the **raw Kaolin (KN)** adsorbent. It represents the amount of dye adsorbed per gram of KN. | | **Qe\_KNAlg** | milligrams per gram (mg/g) | The equilibrium adsorption capacity of the **Alginate-modified Kaolin (KN\@Alg)** composite adsorbent. | | **Qe\_AC** | milligrams per gram (mg/g) | The equilibrium adsorption capacity of the **Activated Carbon (AC)**, used as a commercial benchmark for comparison. | |   | | | **The effect of adsorbent dosage** This dataset contains experimental results from a study investigating the effect of adsorbent dosage on the removal of CTC from an aqueous solution. It reports both the adsorption capacity (`Qe`) and the removal efficiency (`R%`) for three different adsorbents across a range of dosages **The effect of solution pH** This dataset contains experimental results from a study investigating the effect of solution pH on the equilibrium adsorption capacity of three different adsorbents for removing CTC from an aqueous solution. **The effect of solution temperature** This dataset contains experimental results from a study investigating the effect of solution temperature on the equilibrium adsorption capacity of three different adsorbents for removing  CTC from an aqueous solution. | **Column Name** | **Units** | **Description** | | :-------------- | :--------- | :-------------------------------------------------------------------------- | | **T** | Kelvin (K) | The temperature of the system, controlled during the adsorption experiment. | **Regeneration study** This dataset contains experimental results from a study investigating the reusability and regeneration efficiency of three spent adsorbents. The study compares the effectiveness of different eluting agents (water, HCl, and NaCl) in desorbing the CTC and restoring the adsorption capacity of the materials over multiple cycles. The dataset is structured in three blocks, one for each adsorbent. Each block contains the following columns: | **Column Name** | **Units** | **Description** | | :------------------------------- | :---------- | :----------------------------------------------------------------------------------------------------------- | | **cycle** | (unitless) | The regeneration and reuse cycle number. Cycle 0 represents the initial performance of the fresh adsorbent. | | **R\_H2O** | percent (%) | The removal efficiency of the adsorbent regenerated with **Deionized Water** for that cycle. | | **R\_HCl** | percent (%) | The removal efficiency of the adsorbent regenerated with **Dilute Hydrochloric Acid (HCl)** for that cycle. | | **R\_NaCl** | percent (%) | The removal efficiency of the adsorbent regenerated with **Sodium Chloride (NaCl)** solution for that cycle. | | **Solid Phase Extraction (SPE)** | | | This dataset evaluates the efficiency of a Solid Phase Extraction (SPE) protocol for pre-concentrating residual Chlortetracycline (CTC) from aqueous solution after adsorption experiments with Alginate-Modified Kaolinite (Alg@KN). The study compares the recovery rate of CTC from the supernatant across three different water matrices to assess the impact of water chemistry on the analytical method's effectiveness. ## Code/software EXCEL or ORIGIN