Efficient removal of tartrazine from aqueous solutions by solid sorbents

Facile Fabrication of Porous Adsorbent with Multiple Amine Groups for Efficient and Selective Removal of Amaranth and Tartrazine Dyes from Water

The development of an advanced dye adsorbent that possesses a range of beneficial characteristics, such as high adsorption capacity, swift adsorption kinetics, selective adsorption capability, and robust reusability, remains a challenge. This study introduces a facile method for fabricating an amine-rich porous adsorbent (ARPA), which is specifically engineered for the adsorptive removal of anionic dyes from aqueous solutions. Through a comprehensive assessment, we have evaluated the adsorption performance of ARPA using two benchmark dyes: amaranth (ART) and tartrazine (TTZ). Our findings indicate that the adsorption process reaches equilibrium in a remarkably short timeframe of just 20 min, and it exhibits an excellent correlation with both the Langmuir isotherm model and the pseudo-second-order kinetic model. Furthermore, ARPA has demonstrated an exceptional maximum adsorption capacity, with values of 675.68 mg g-1 for ART and 534.76 mg g-1 for TTZ. In addition to its high adsorption capacity, ARPA has also shown remarkable selectivity, as evidenced by its ability to selectively adsorb TTZ from a mixed dye solution, a feature that is highly desirable for practical applications. Beyond its impressive adsorption capabilities, ARPA can be efficiently regenerated and recycled. It maintains a high level of original removal efficiency for both ART (76.8%) and TTZ (78.9%) even after five consecutive cycles of adsorption and desorption. Considering the simplicity of its synthesis and its outstanding adsorption performance, ARPA emerges as a highly promising material for use in dye removal applications. Consequently, this paper presents a straightforward and feasible method for the production of an effective dye adsorbent for environmental remediation.

Preparation of room-temperature phosphorescence-ratiometric fluorescence magnetic mesoporous imprinted microspheres and its application in detection of malachite green and tartrazine in multimatrix

The photoluminescent properties of Mn-doped ZnS quantum dots were fully exploited, and room-temperature phosphorescence (RTP)-ratiometric fluorescence (RF) magnetic mesoporous molecularly imprinted polymers (PFMM-MIPs) were prepared by integrating molecular imprinting technology. RTP was used to detect malachite green (MG). The fluorescence at 420 nm and the peak at 590 nm in the fluorescence mode were used as the response reference signals respectively to detect tartrazine (TZ). The linear responsive range and detection limit of MG were 0.01-150 μM and 4.3 nM, and these of TZ were 0.05-80 μM and 23.7 nM. RTP, which can avoid the interference of background fluorescence, and RF with self-calibration ability can both largely weaken the matrix effect. This work enables single-probe-type MIPs to achieve dual-target analysis via RTP and RF. This method provides excellent sensitivity, specificity, recovery and recyclability, and is expected to be prospectively applied in the fields of food, environment and biological analyses.

Separation and quantification of Tartrazine (E102) and Brilliant Blue FCF (E133) in green colored foods and beverages

In the present study we investigated the capacities of a panel of 25 solid sorbents represented by layered structures, inorganic oxides and hydroxides, and phyllosilicates, to effectively remove in high yield Tartrazine (E102) and Brilliant Blue FCF (E133) from aqueous solutions, and more notable, green colored food matrices. Quantification of the title compounds have been achieved by HPLC-DAD analyses. Contents of E102 and E133 in real samples were in the range 1.3-36.5 μg/mL and 1.0-20.1 μg/mL, respectively. After a treatment of 1 min., in most cases a complete bleaching of solutions and deep coloring of the solid phase was recorded. The most effective solids to this aim were seen to be aluminium based ayered double hydroxides. In the case of magnesium oxide for E102, and magnesium aluminium D. benzensulfonate SDS 01 H8L and Florisil for E133, a selective adsorption (>99.9 %) of only one dye was observed. The adsorption recorded was strictly dependent on the loading of the sorbent. Related values were 300 mg for the separation of E102 by magnesium oxide from all the five food matrices under investigation, and in the range 200 mg-300 mg for magnesium aluminium D. benzensulfonate SDS 01 H8L and Florisil in the case of E133. The application of Langmuir and Freundlich models suggested that the adsorption may take place in the inner layers of the solids with a favourable thermodynamique outcome. Findings described herein offer the concrete possibility of quantifications of individual dyes in matrices containing more than one food colorant.

Thermodynamics, kinetics and isothermal studies of tartrazine adsorption onto microcline/MWCNTs nanocomposite and the regeneration potentials

The quest for a cheap, effective, and eco-friendly wastewater treatment technique that is free of secondary toxic byproducts, calls for the fabrication of a nature-friendly adsorbent with a robust capacity to decontaminate polluted water sources and be recycled. To this end, we report the fabrication of novel nanocomposite (KMCM) from microcline (KMC) and multiwall carbon nanotubes (MWCNTs). The adsorbents (KMC and KMCM) were characterized using XRD, BET, SEM, TGA and FTIR. The novel and low-cost nano sorbent were designed for the elimination of tartrazine (Tatz) from wastewater. The adsorption of Tatz onto KMC and KMCM was influenced by adsorbent dose, initial Tatz concentration, contact time and solution pH. Experimental data acquired from the equilibrium studies were well addressed by the Langmuir isotherm model. The maximum uptake capacity of 37.96 mg g^-1 and 67.17 mg g^-1 were estimated for KMC and KMCM. The kinetics for the adsorption of Tatz onto KMC and KMCM was best expressed by pseudo-second-order and Elovich models. The thermodynamic parameters revealed that the uptake of Tatz onto KMC and KMCM was an endothermic (ΔH: KMC = 35.0 kJ mol^-1 and KMCM = 42.91 kJ mol^-1), entropy-driven (ΔS: KMC = 177.6 J K^-1 mol^-1 and KMCM = 214.2 J K^-1 mol^-1) and spontaneous process. Meanwhile, KMCM demonstrated good reusability potential and superior adsorption efficiency when compared to other adsorbents.

Light-powered swarming phoretic antimony chalcogenide-based microrobots with "on-the-fly" photodegradation abilities

Microrobots are at the forefront of research for biomedical and environmental applications. Whereas a single microrobot exhibits quite low performance in the large-scale environment, swarms of microrobots are representing a powerful tool in biomedical and environmental applications. Here, we fabricated phoretic Sb₂S₃-based microrobots that exhibited swarming behavior under light illumination without any addition of chemical fuel. The microrobots were prepared in an environmentally friendly way by reacting the precursors with bio-originated templates in aqueous solution in a microwave reactor. The crystalline Sb₂S₃ material provided the microrobots with interesting optical and semiconductive properties. Because of the formation of reactive oxygen species (ROS) upon light illumination, the microrobots possessed photocatalytic properties. To demonstrate the photocatalytic abilities, industrially used dyes, quinoline yellow and tartrazine were degraded using microrobots in the "on-the-fly" mode. Overall, this proof-of-concept work showed that Sb₂S₃ photoactive material is suitable for designing swarming microrobots for environmental remediation applications.