Indigo Carmine Research Articles

Investigation of process parameters for eco-friendly indigo dyeing of cotton fabric with reducing sugars

Purpose The application of indigo dyes in the denim industries has been criticised due to the introduction of non-renewable oxidation products into the environment. Previous studies have investigated that reducing sugars can be used as green alternatives to sodium dithionite in the indigo dyeing of cotton fabric owing to their reduced and stable redox potential in the dye bath. The purpose of this study was to dye denim cotton fabric with indigo dye using various reducing sugars and alkalis. The use of sucrose and potassium hydroxide (KOH) for indigo dyeing has been explored for the first time. Design/methodology/approach A mixed factorial design with four variables including alkali, pH, number of dips and type of reducing sugar at different levels was studied to identify a significant correlation between the effect of these variables on the colour strength and fastness properties of the dyeings. Findings Investigations were made to examine the significant factors and interactions of the selected responses in the eco-friendly dyeing method. This process has the potential to reduce the load of sulphite and sulphate generated in the dyebath due to the use of a conventional reducing agent, sodium dithionite. The colour strength of the dyeing reduced with fructose was found to be better than other reducing sugars and significantly influenced by the number of dips, pH levels and the interaction between pH and reducing sugars. Using fructose for indigo dyeing with two dips at a pH of 11.5, using KOH as an alkali, results in higher colour strength values. The fastness properties of the indigo-dyed sample with reducing sugars ranging from fair to good or good to excellent. Specifically, colour change receives a rating of grey scale 3–4, staining 4–5, dry rubbing 4 and light fastness 3–4. These assessments hold true across various factors such as the type of reducing sugar, alkali, pH and the number of dips. The optimised parameters leading to improved colour strength and fastness properties are also discussed. Originality/value This dyeing technique is novel and a green alternative to dithionite denim dyeing. This process is found to be useful for indigo dyeing of denim fabric leading to reduced and stable redox potential in the dyebath and acceptable colour strength of the dyed fabric.

Removal of tartrazine and indigo carmine with layered double hydroxide-modified graphite nanocomposite: Isotherm, kinetics and response surface methodology (RSM) optimization

This research in focus investigates the removal of tartrazine (TZ) and indigo carmine (IC) dyes utilizing an AlCuFe-LDH/C nanocomposite as an adsorbent. The composite underwent comprehensive characterization through FE-SEM, EDX, FT-IR, XRD, and BET analyses. To gauge the efficacy of TZ and IC removal with the powdered adsorbent in use, the nanocomposites performance in surface adsorption of dyes species optimized, designed, and tested. Various parameters influencing the dyes adsorption under optimal conditions were considered, with a pH of 6.0 and an adsorption process time of 13 min selected. The concentrations of IC and TZ solutions were set at 11.5 mg/L, while a mass of 0.0143 g of adsorbent was applied. Under these conditions, the adsorbent exhibited impressive capabilities, removing 99.20 % of TZ and 88.5 % of IC. Equilibrium data were fitted to Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich models, with the Langmuir isotherm model found to be the most fitting. Based on the Langmuir isotherm model, the adsorption capacities were determined to be 26.05 mg g−1 for TZ, 26.56 mg g−1 for IC. Additionally, the kinetic evaluation of experiments conducted at various time intervals revealed that the adsorption processes aligned well with second-order kinetic models. Regeneration studies indicated that the adsorbent could successfully retain dyes even after four cycles, with the adsorption percentage of AlCuFe-LDH/C for dyes remaining at 80 % after four adsorption–desorption cycles.

Synthesis and characterization of Ag@M-BTC (M = Zn & Cd) Nanocomposites for efficient removal of methylene blue and indigo carmine

Two MOF based composite materials decorated with Ag NPs viz. Ag@M-BTC (BTC= 1,3,5-benzenetricarboxylate; M=Zn & Cd) were synthesised and characterized using various physicochemical techniques, including FT-IR, PXRD, FE-SEM, EDX, HR-TEM, BET and XPS. The FT-IR spectra of the nanocomposites (NCs) and the pristine MOFs suggest retention of the MOF structure in the resulting composite materials and the PXRD patterns confirm the presence of metallic Ag within the crystalline phase of the MOFs. The observed rough surfaces on the NCs as evidenced from FE-SEM micrographs, indicates the deposition of Ag NPs on the surface of the MOFs. Furthermore, HR-TEM images reveal the presence of nanosized Ag aggregates of spherical shape inside the MOF matrix as well as on the surface. The adsorption activity of the synthesised NCs have been assessed for Methylene Blue (MB) and Indigo Carmine (IC). It is observed that the NCs, Ag@Zn-BTC (1a) and Ag@Cd-BTC (2a) performs better degradation as compared to that of pristine MOFs. These NCs can degrade MB completely (100 %) after 50 min treatment time, while maximum 91 % degradation was recorded for the IC dye. Here, the degradation process can be thought of as operating via chemisorption phenomena, supported by theoretical calculations. Additionally, these NCs can be reused up-to three times for the effective degradation of dyes.

Adsorption of Brilliant blue FCF (B1) and Allura Red (R40) colorants on cocoa shell: kinetics of the process

The use of dyes in food industrial processes is limited due to significant pollution in aquatic receptors from their wastewater. To address this issue, this study focused on evaluating the adsorption of dyes Allura Red (R40) and Brilliant blue FCF (B1) using cocoa shells (CS) as an absorbent. To achieve this, a pre-treatment was applied, which involved washing, grinding and drying at a temperature of 80 °C for 24 h, followed by a sieving process. The effect of the adsorbent dose was then analyzed and it was calculated that the optimal dose was 4 g/L. Additionally, the effect of contact time was studied through a kinetic analysis, all tests were carried out at a pH level of 2. The obtained data were fitted to kinetic models, which allowed us to conclude that the adsorption kinetics fit two different models depending on the initial solution conditions, in a range from 0 to 0.1512 mmol/L. Specifically, the Pseudo Second-Order (PSO) model fitted R40, while the Elovich model was appropriate for B1. In summary, CS was found to be a viable adsorbent for dyes in contaminated waters.

Rapid determination of polyhalogenated carbazoles in water chestnut based on vortex assisted solvent extraction coupled with dispersive filter extraction followed by gas chromatography-tandem mass spectrometry

Polyhalogenated carbazoles (PHCZs), originating from the production and use of halogenated indigo dyes, photoelectric materials, and p-chloraniline structure herbicides, pose a threat to water environments, aquatic products, and consequently human health. Therefore, establishing an accurate detection method for PHCZs in aquatic products is of paramount importance. In this study, trace PHCZs (36-CCZ, 36-BCZ, and 1368-BCZ) in water chestnut were detected for the first time using the prepared polyvinyl alcohol-functionalized graphene aerogel (PGA) as a novel adsorbent for dispersive filter extraction (DFE), coupled with vortex assisted solvent extraction (VASE), followed by gas chromatography-tandem mass spectrometry (GC–MS/MS). The extraction process (VASE-DFE) has the advantages of good purification effect, short extraction time (<15 min), and low adsorbent dosage (1.0 mg). This method demonstrated excellent linearity in the range of 0.10/0.50/1.00–200 ng/g for the three PHCZs (R2 ≥ 0.9995), and the recoveries at three spiked levels (2, 20, 100 ng/g) ranged from 82 % to 93 %, with relative standard deviations (RSDs) ≤ 7.4 %. Notably, the method outperforms previously reported adsorbents in terms of RSDs, adsorbent dosage, and extraction time. The VASE-DFE-GC–MS/MS method provides a new approach for the detection of trace pollutants in complex samples, introduces a novel technology for environmental and food safety monitoring, and contributes to enhancing food safety supervision.

Competition between indigo carmine and water in the formation of dynamics behavior at different temperatures

We apply molecular dynamics methods to determine the impact of temperature on the structural and dynamic properties of aqueous solution of indigo carmine at temperatures between 300 and 323 К. We report that indigo carmine motion changes from the sub-diffuse to the diffuse regime at t = 100 ps, while water molecules continue to move in the slowed sub-diffuse regime. We demonstrate that the determining factor in the change of the structural and dynamic properties of the aqueous solution of indigo carmine at temperatures between 300 and 323 K is the change in the local structure of water and that the presence of indigo carmine leads to the decrease in temperatures at which a slowed motion of solution components is observed.

A comprehensive study on the development of ceramic membranes from natural Kashmir clay and its application in pH-mediated removal of Indigo carmine dye

A comprehensive study on the development of ceramic membranes from natural Kashmir clay and its application in pH-mediated removal of Indigo carmine dye

In-silico and in-vitro targeting of organic dye pollutants from synthetic and real wastewater by the hierarchically self-assembled laccase@bismuth phosphate hybrid nanorods

The increasing presence of dyes in wastewater and even surface or groundwater has progressively become an emerging global concern. This study evaluated the potential use of facile, straightforward, and hierarchical laccase@BiPO4•hybrid nanostructures (HNSs) in the elimination of anthraquinone, monoazo, diazo, and triarylmethane dyes from municipal wastewater through in-silico and in-vitro analyses. The prepared HNSs possessed rod-like morphological features with more than 8 cycles of reusability and about 10 U mg–1 catalytic activity. The nitrogen sorption analysis revealed that the prepared HNRs presented a Brunauer-Emmett-Teller (BET) surface area of 15.3 ± 1.6 m2 g−1 and an average pore size of 9.7 ± 0.5 nm. The total pore volume of HNRs was also measured at 4.0 ± 0.1 (× 10−2 cm3 g−1). Molecular docking predicted the preferred orientation of dye molecules with the enzyme's active site, facilitating the formation of stable complexes. The constructed hybrid nanorods (HNRs) showed proper in-vitro oxidation activity on the pollutant dyes with a more than 95% bioremoval for Direct Blue-15, Direct Blue-71, Crystal Violet, and Acid Blue-92. The maximum adsorption capacity of the prepared HNRs was 401 ± 11 mg per g of the carrier after 240 min of contact time with initial dyes' concentrations. Freundlich isotherm well fitted on the removal data compared with the Langmuir model due to the formation of a uniform monolayer of the dyes onto the prepared HNRs. For Direct Blue-15, Direct Blue-71, Crystal Violet, Acid Blue-92, and Acid Red-18, R2 values of pseudo-second-order kinetic were closer to 1 than that of first-order. The thermodynamic evaluations indicated that the removal of the dyes by the immobilized enzyme proceeded spontaneously and favorably (0 > ΔG°), albeit with endothermic characteristics (0 < ΔH°). Bioremoval efficiencies of 32%, 51%, 64%, and 72% were recorded when actual wastewater samples underwent treatment with 0.3 U mL−1, 0.6 U mL−1, 0.9 U mL−1and 1.2 ≤ U mL−1 of HNPs, respectively. Furthermore, the enzymatic removal process led to less toxic metabolites as confirmed using the bacterial growth inhibition test. Therefore, laccase@BiPO4•HNRs can be a worthy approach in dye removal from wastewater due to their distinct physicochemical and catalytic properties.

Computational analysis of anionic dyes adsorption on the kaolinite (001) surface: Combination of quantum chemical calculations and molecular simulation methods

Clay minerals are increasingly used to remove dyes from wastewater. In recent times, computational simulation methods have become indispensable for investigating the adsorption mechanisms of dyes on clay surfaces at the molecular level. This study investigates the adsorption features of two acid dyes, namely acid blue 25 (AB25) and acid red 88 (AR88), on the (001) surface of kaolinite in an aqueous medium using density functional theory (DFT), Monte Carlo (MC), and molecular dynamics (MD) simulations. Quantum chemical parameters (QCPs) show that the AB25 molecule exhibits higher reactivity compared to the AR88 molecule. As well, analysis of the sigma profile reveals a moderate polarity of the two dye molecules studied in comparison with the water molecule. The low-energy adsorption configuration of AB25 and AR88 molecules show that each molecule is oriented parallel to the (001) surface of kaolinite over short distances. The adsorption energies indicate that the kaolinite (001) surface has high affinity towards AB25 in comparison with the AR88 molecule (Eads(AB25) = -926.01 Kcal.mol−1; Eads(AR88) = -742.08 Kcal.mol−1), which was supported by analysis of the self-diffusion coefficient (SDC) values (SDCAB25 = 7.79 × 10-10 m2.s−1; SDCAR88 = 1.4 × 10-9 m2.s−1). Additionally, calculation of the radial distribution function of the oxygen and nitrogen atoms of AB25 and AR88 molecules show the contribution of these atoms in the chemical interactions that take place with the (001) surface of kaolinite. The adsorption mechanism of the investigated dye molecules may be influenced by both donor–acceptor and van der Waals interactions. The theoretical results from this study could be useful for better understanding the adsorption mechanisms of other acid dyes on clay minerals.

Inhibition of pannexin-1 does not restore electrolyte balance in precystic Pkd1 knockout mice.

Mutations in PKD1 and PKD2 cause autosomal dominant polycystic kidney disease (ADPKD), which is characterized by the formation of fluid-filled cysts in the kidney. In a subset of ADPKD patients, reduced blood calcium (Ca2+) and magnesium (Mg2+) concentrations are observed. As cystic fluid contains increased ATP concentrations and purinergic signaling reduces electrolyte reabsorption, we hypothesized that inhibiting ATP release could normalize blood Ca2+ and Mg2+ levels in ADPKD. Inducible kidney-specific Pkd1 knockout mice (iKsp-Pkd1-/-) exhibit hypocalcemia and hypomagnesemia in a precystic stage and show increased expression of the ATP-release channel pannexin-1. Therefore, we administered the pannexin-1 inhibitor brilliant blue-FCF (BB-FCF) every other day from Day 3 to 28 post-induction of Pkd1 gene inactivation. On Day 29, both serum Ca2+ and Mg2+ concentrations were reduced in iKsp-Pkd1-/- mice, while urinary Ca2+ and Mg2+ excretion was similar between the genotypes. However, serum and urinary levels of Ca2+ and Mg2+ were unaltered by BB-FCF treatment, regardless of genotype. BB-FCF did significantly decrease gene expression of the ion channels Trpm6 and Trpv5 in both control and iKsp-Pkd1-/- mice. Finally, no renoprotective effects of BB-FCF treatment were observed in iKsp-Pkd1-/- mice. Thus, administration of BB-FCF failed to normalize serum Ca2+ and Mg2+ levels.

Synthesis and characterization of bi-functional Cu and Ni co-doped ZnO photocatalysts for organic pollutant degradation and antimicrobial activity

The study of visible light active photocatalysts for organic pollutants degradation and antimicrobial activity has gained significant attention in recent years. Herein, we report the synthesis of pure ZnO, Ni-doped ZnO (Ni-ZnO), Cu-doped ZnO (Cu-ZnO), and Cu and Ni co-doped ZnO (CuNi-ZnO) photocatalysts via a facile coprecipitation method. These photocatalyst materials were characterized using various analytical techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscope (HR-TEM), Fourier transform infrared spectroscopy (FTIR), UV–visible spectroscopy (UV–Vis), photoluminescence (PL), and total organic carbon (TOC) analysis. XRD patterns confirm the presence of a mixed phase in the CuNi-ZnO sample. The presence of Cu, Ni, and Zn in CuNi-ZnO was verified through the XPS spectra. The nanoparticle-like morphology of the CuNi-ZnO photocatalyst was confirmed using HRTEM analysis. The FTIR spectra reveal the chemical bonds present in the materials. UV–visible spectroscopy was employed to determine the band gap of the materials, revealing a value of 3.10 eV for CuNi-ZnO. The mitigation in recombination of excited electrons (e−) and holes (h+) in CuNi-ZnO is validated through photoluminescence (PL) studies. The synthesized materials were used for the degradation of Indigo carmine (IC) dye and antimicrobial activity. The results showed that the optimized CuNi-ZnO sample displayed a better visible light photocatalytic performance (93.32 % IC dye degradation efficiency in 60 min) than the other samples. A notable degree of mineralization was observed with a reduction in total organic carbon (TOC) reaching 65.91 %. Additionally, the photocatalyst showed antimicrobial activity against both S. aureus and E. coli. Furthermore, a plausible visible light photocatalytic mechanism was proposed for the degradation of IC dye using the CuNi-ZnO photocatalyst.

Extraction of natural dyes from tarum leaves (Indigofera Tinctoria L.) using the Ultrasound-Assisted Extraction (UAE) method

The rapid development of the textile industry has led to increased use of synthetic dyes. Although synthetic dyes are more practical and economical, their use can have adverse effects on health and the environment. Natural dyes are utilized as alternatives with indigo leaves (Indigofera tinctoria L.) being one source known for producing a blue color. However, the commonly used extraction methods require long extraction times and significant solvent consumption. Given the limitations of current methods, innovation is needed for an efficient extraction method that produces safe and environmentally friendly natural dyes, one of which is ultrasound-assisted extraction (UAE). Therefore, this study aims to determine the extraction process of indigo leaves using UAE method, then identify the parameters influencing the extraction process using the UAE, determine the extraction yield using UAE, assess the dyeing results of the extracted dye from indigo leaves on cotton fabric, and compare the extraction results of indigo dye through the UAE method with the addition of CaO and NaOH solutions. The results of this study indicate that the natural dye from Indigofera tinctoria obtained the best conditions at extraction time of 90 min, feed-to-solvent ratio of 0.05 g/ml, and CaO-to-solvent ratio of 0.005 g/ml. Furthermore, the addition of CaO solution obtained the highest yield at 4.25 %, while the addition of NaOH solution resulted in 4.8 %. Additionally, the analysis and test results of the application of natural dye from Indigofera tinctoria on cotton fabric revealed a darker color with the addition of NaOH solution compared to the addition of CaO solution.

Simultaneous degradation of methyl orange and indigo carmine dyes from an aqueous solution using nanostructured WO3 and CuO supported on Zeolite 4A

In this study, a novel composite catalyst system, Zeolite 4A/WO3/CuO with a Z-scheme design, was synthesized for photocatalysis, sonocatalysis, and sono-photocatalysis methyl orange (MO) and indigo carmine (IC) dyes simultaneously. The properties of the Zeolite 4A/WO3/CuO composite were thoroughly investigated using various techniques, and the results confirmed the synthesis of the desired catalyst system. In the sono-photocatalytic process, using the Zeolite 4A/WO3/CuO composite, the maximum efficiency for MO (99.12 %) and IC (97.24 %) was achieved at pH of 2 and 3, with a catalyst dosage of 0.15 g/L, a dye concentration of 10 mg/L, a contact time of 25 min, and H2O2 dosage of 30 µL/100 mL. The dye elimination efficiency using the sono-photocatalytic process was reduced in the presence of Cl- and PO43- in the distilled water. The efficiency also declined in the medium of river and well water resources. Moreover, the Zeolite 4A/WO3/CuO catalyst maintained over 90 % of its performance even after five reuse cycles. Based on the kinetic study, the sono-photocatalytic process exhibited higher activation for the removal of MO (k: 0.1946 min−1 and t1/2: 3.561) and IC (k: 0.1433 min−1 and t1/2: 4.836) than other processes. The synergy values for the MO and IC degradation using the Zeolite 4A/WO3/CuO composite were determined to be 2.167 and 2.303, respectively. The impact of various scavengers demonstrated that in the degradation processes of the target dyes using the sono-photocatalytic process, different active species like OH•, e-, h+, and O2–• are involved. The purification of dye-laden water using the sono-photocatalytic process was not toxic for plant germination, microorganisms, and fish, highlighting the successful biocompatibility of the process for dye removal.

Indigo dyes: Toxicity, teratogenicity, and genotoxicity studies in zebrafish embryos

Wastewater released by textile dyeing industries is a major source of pollution. Untreated wastewater released from indigo dyeing operations affects aquatic ecosystems and threatens their biodiversity. We have assessed the toxicity of natural and synthetic indigo dye in zebrafish embryos, using the endpoints of teratogenicity, genotoxicity, and histopathology. The zebrafish embryo toxicity test (ZFET) was conducted, exposing embryos to ten concentrations of natural and synthetic indigo dyes; the 96-hour LC50 values were approximately 350 and 300 mg/L, respectively. Both dyes were teratogenic, causing egg coagulation, tail detachment, yolk sac edema, pericardial edema, and tail bend, with no significant difference in effects between the natural and synthetic dyes. Both dyes were genotoxic (using comet assay for DNA damage). Real-time RT-PCR studies showed upregulation of the DNA-repair genes FEN1 and ERCC1. Severe histological changes were seen in zebrafish larvae following exposure to the dyes. Our results show that indigo dyes may be teratogenic and genotoxic to aquatic organisms, underscoring the need for development of sustainable practices and policies for mitigating the environmental impacts of textile dyeing.

A New Approach of Complexing Polymers Used for the Removal of Cu2+ Ions.

This study presents two modified polymers for Cu2+ ion removal from aqueous media. Shredded maize stalk (MC) and a strong-base anionic resin (SAX) were modified with indigo carmine (IC) in order to obtain two different complexing polymers, i.e., IC-MC and SAX-IC. Initially, the complex reaction between IC and Cu2+ in the solution was studied. Additionally, the complex formation Cu2+-IC in liquid solutions was evaluated at different pH ranges of 1.5, 4.0, 6.0, 8.0, and 10.0, respectively. For Cu2+ ions, adsorption onto the IC-MC and IC-SAX batch experiments were conducted. The contact time for evaluating the optimum adsorption for Cu2+ ions on the complexing materials was established at 1 h. Efficient Cu2+ ion adsorption on the IC-MC and SAX-IC at pH = 10 was achieved. The adsorption of Cu2+ ions depends on the quantity of IC retained on MC and SAX. At 2.63 mg IC/g MC(S4) and 22 mg IC/g SAX(SR2), a high amount of Cu2+ ion adsorption was reported. The highest adsorption capacity (Qe) of IC-MC was obtained at 0.73 mg/g, and for IC-SAX, it was attained at 10.8 mg/g. Reusability experiments were performed using the HCl (0.5 M) solution. High regeneration and reusability studies of IC-MC and IC-SAX were confirmed, suggesting that they can be used many times to remove Cu2+ ions from aqueous matrices. Therefore, the development of complexing materials could be suitable for Cu2+ ion removal from wastewater.

Electrocatalytic recycling of indigo dye from waste denim fabric: an engineering approach toward efficient denim dye reuse

The denim fabric industry has experienced exponential growth and escalating concerns regarding sustainable production and recycling practices. The wide utilization of indigo dye in denim manufacturing presents significant challenges owing to its intricate chemical structure and inherent resistance to degradation. Improper disposal of waste denim fabric and the release of indigo dye impose severe ecological ramifications. In this study, we explore the productive application of electrochemistry to recycle indigo dye from waste denim fabric while repurposing the electrolyte for denim dyeing. Notably, the separation of indigo from waste denim textiles reaches 82.34%. It is calculated that 21.59 g of indigo can be recovered from 1 kg of denim waste. Recovered indigo can be reused for cotton yarn dyeing. In the experiment, indigo was recovered from 0.03 square meters of denim waste, and the K/ S value of the yarn was up to 2.997 after five dyeing cycles. The loss of fabric strength after recycling is as low as 13.32%, which has little effect on secondary fabric recycling. Our recycling method reduces the waste of 978.41 g of waste fabric and 21.59 g of indigo per kilo compared to conventional treatment. This research provides compelling scientific evidence supporting adopting a closed-loop system within denim production, underlining the potential for environmentally conscious and economically viable practices in the industry.

Rapid quantitative analysis of natural indigo dye content using near-infrared spectroscopy

Natural indigo, the most widely produced and utilized natural dye, encounters quality challenges due to the lack of standardization in the natural dye industry. Rapid determination of natural indigo dye contents before the dyeing process appears extremely important. In this study, two prediction models for different concentrations were established using partial least squares in conjunction with near-infrared analysis quantitatively to analyze the natural indigo dye content. A total of 228 indigo samples were collected from 14 different dyestuffs across various regions, with concentrations ranging from 100 to 1000 mg/L and 10 to 100 mg/L, respectively. The spectral pre-processing methods of multiplicative scatter correction plus first-order derivative and Savitzky–Golay smoothing plus band normalization plus first-order derivative were selected to enhance the model prediction accuracy. The optimized model exhibited excellent prediction accuracy. Within the concentration range of 100–1000 mg/L, the model has an R2 value of 0.9994, and a root mean square error of prediction value of 6.36 mg/L. In the concentration range of 10–100 mg/L, the model returned an R2 value of 0.9907, and a root mean square error of prediction value of 2.80 mg/L. The model's detection limit stands at 49.2 mg/L. The results demonstrated that the near-infrared models developed in this study can be used rapidly and accurately for the quantitative determination of natural indigo dyes.

Chest wall tuberculosis: Precision surgery with indigo carmine in limited cases for safe and intuitive lesion excision.

In addition to treatment with antituberculosis drugs, complete surgical excision is important for the cure of chest wall tuberculosis. However, surgery is often challenging to perform due to different factors such as the strong adhesion of tuberculous lesions to the surrounding normal tissue, growth of neovascularization, and presence of fragile necrotic tissues. Firm adhesions, bleeding, and fragile tissue make it difficult to determine the boundary with normal tissue and completely excide the lesion. Moreover, ingenuity is required. Herein, we report the identification of the boundary between the lesion and normal tissue by injecting indigo carmine into the abscess to completely excide the lesion, which is considered an intuitive and safe method.

Treatment of real textile effluent containing indigo blue dye by hybrid system combining adsorption and membrane processes

The rapid expansion of the textile industry in Tunisia has resulted in ever-increasing discharges of wastewater, making it necessary to set up treatment systems allowing i) its discharge into the environment or ii) to recycle the water in the textile plant. In this study, several unitary operations were tested in order to improve the treated water quality. Thus, the following unit operations were applied: adsorption using Natural Clay (NC) and Powdered Activated Carbon (PAC), ultrafiltration (UF) and nanofiltration (NF) individually or in synergy: UF, nanofiltration, PAC-UF, NC-UF, UF-NF et Adsorption-UF/NF. The experiments were carried out on real textile effluent containing Indigo blue dye. A threshold concentration was observed above which performance no longer increases. NF alone showed better reduction of COD (67%), color (78%), and turbidity (98%) than UF alone (26%, 48%, 95%, respectively). The coupling UF–NF showed a clear improvement in water quality in terms of color (99%) and COD (98%) with an improvement in the NF flux from 67.81 L/h.m2 to 90.62 L/h.m2. No fouling was observed for NF while it is significant during UF. The used of adsorption as pretreatment to filtration leads to an enhancement of the treatment performances with a removal of 99.9%, 99.5% and 79.5% respectively for turbidity, color and COD for NC-UF and a removal of 100%, 99.4% and 79.6% respectively for turbidity, color and COD for PAC-UF. Moreover, the addition of adsorbent controls the fouling and a constant and high flux is quickly attained and remains stable over time. The use of natural clay as adsorbent represents an economically profitable solution since it can be obtained locally and the clay used can be reused in the ceramic industry as an additive for road surfacing without the need for regeneration.

Effect of conductive polyaniline on the cationic and anionic dye adsorption properties of amphoteric alginate/chitosan composite foams

Doped polyaniline is a widely used conductive material and could be used for adsorption based on the electrostatic neutralization effect through the protonation of the imine group. However, the adsorption effect and mechanism towards cationic and anionic pollutants are not clear. Herein, the conductive sulfonic acid doped polyaniline was introduced into alginate/chitosan amphoteric composite foams prepared with a thermal induced phase separation technique. The composite foams were characterized in terms of scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and electrochemical impedance. The composite foam exhibited rich pores and fibrous matrix due to the unique ternary solvent system. The polyaniline was well-distributed and enhanced the cationic dye adsorption ability, contrary to that of anionic dye. Compared with pure alginate/chitosan composite foam, the adsorption capacity of methylene blue was increased by 91.1%, and that of acid blue-113 was reduced by 49.2%. The adsorption rate of the two dyes was both increased. Polyaniline addition enhances the ionic mobility rate and accelerates the movement of dye molecules. Moreover, the composite foams exhibited excellent selective adsorption capacity and reusability. The study indicates that the conductive polymer could find its share in developing high-performance adsorbents.