Preparation of Functionalized Hydroxyapatite with Biopolymers as Efficient Adsorbents of Methylene Blue

In this study, we reported the synthesis of hydroxyapatite modified with biopolymers as λ-carrageenan and sodium alginate, which could be used as effective adsorbents of cationic dyes. Evidence of chemical modification was proved through chemical analysis, Fourier Trans-form Infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, and specific surface area. The adsorption process was studied using methylene blue as representative cationic dye. The adsorbed quantity reached, at equilibrium, 142.85 mg/g and 98.23 mg/g using hydroxyapatite-sodium alginate and hydroxyapatite-(λ-carrageenan), respectively. However, it does not exceed 58.8 mg/g in the case of the unmodified hydroxyapatite. The adsorption of methylene blue using hybrid materials complied well with the pseudo-second-order suggesting a chemi-sorption. Freundlich and Langmuir isotherm described well the adsorption mechanism of the hydroxyapatite-(λ-carrageenan) and hydroxyapatite-sodium alginate, respectively. The high capacities of MB removal obtained in this study suggest the potential use of these materials in the treatment from wastewaters

2,4-Bis(arylethynyl)-9-chloro-5,6,7,8-tetrahydroacridines: synthesis and photophysical properties

Acridine derivatives have attracted considerable interest in numerous areas owing to their attractive physical and chemical properties. Herein, starting from readily available anthranilic acid, an efficient synthesis of 2,4-bis(arylethynyl)-9-chloro-5,6,7,8-tetrahydroacridine derivatives was accomplished via a one-pot double Sonogashira cross-coupling method. The UV-visible absorption and emission properties of the synthesized molecules have been examined. Additionally, theoretical studies based on density functional theory (DFT/B3LYP/6-31G(d)) were carried out

<i>Garlic</i> Cellulosic Powders with Immobilized AgO and CuO Nanoparticles: Preparation, Characterization of the Nanocomposites, and Application to the Catalytic Degradation of Azo Dyes

Nanomaterials have attracted specific consideration due to their specific characteristics and uses in several promising fields. In the present study, Chondrilla juncea was employed as a biological extract to facilitate the reduction of copper and silver ions within garlic peel powders. The resulting garlic-CuO and garlic-AgO nanocomposites were characterized using several analytical methods including FTIR, TGA/DTG, SEM, TEM, and XRD analyses. The garlic peel exhibited a rough surface. The nanoparticles were evenly dispersed across its surface. The incorporation of CuO and AgO nanoparticles affected the crystal structure of garlic peel. The establishment of CuO and AgO nanoparticles was evidenced by the highest residual mass values observed for the prepared nanocomposites. The thermogravimetric analysis showed that the prepared nanocomposites had lower thermal stability compared with garlic peel powders. The prepared nanocomposites were used for catalytic degradation of naphthol blue black B and calmagite. The decolorization process depended on the quantity of H2O2, initial concentration of azo dyes, duration of contact, and temperature of the bath. The calculated activation energy (Ea) values for the garlic-CuO nanocomposites were found to be 18.44 kJ mol−1 and 23.28 kJ mol−1 for calmagite and naphthol solutions, respectively. However, those calculated for garlic-AgO nanocomposites were found to be 50.01 kJ mol−1 and 12.44 kJ mol−1 for calmagite and naphthol, respectively

Extraction of Cellulose Polymeric Material from Populus tremula Fibers: Characterization and Application to the Adsorption of Methylene Blue and Crystal Violet

Cellulose is the most widely available biopolymer which is extensively used for several applications including textiles, composites, pharmaceutical, water treatment, etc. In this investigation, cellulose was chemically extracted from Populus tremula seed fibers. Samples were characterized using FT-IR, SEM, XRD, and TGA-DTA analyses. FT-IR spectrum of the extracted cellulose confirmed that hemicellulose and lignin were removed during alkali and bleaching treatments. SEM images showed the partially roughened surface of the fiber due to the removal of non-cellulosic elements and surface impurities during chemical modification. The crystallinity index values for untreated Populus tremula fibers and extracted cellulose were calculated to be 32.8% and 58.9%, respectively. The obvious increase in the crystallinity index for the extracted cellulose confirmed the removal of amorphous compounds present in raw populus. Alkali-treated populus fibers were more thermally stable than raw fibers. All changes observed after alkali and bleaching treatments evidenced the removal of amorphous contents and non-cellulosic components in raw populus fibers. Extracted cellulose exhibited excellent adsorption capacities of methylene blue (140.4 mg g−1) and crystal violet (154 mg g−1). The pseudo second order equation fitted well the kinetic data indicating a chemi-sorption process. The Freundlich model complied well with the experimental data suggesting that the adsorption of the studied dyes was multilayer

Synthesis, Characterization, and Application of Dichloride (5,10,15,20-Tetraphenylporphyrinato) Antimony Functionalized Pectin Biopolymer to Methylene Blue Adsorption

In this work, pectin biopolymers were functionalized with dichloride (5,10,15,20-tetraphenylporphyrinato) antimony [Sb(TPP)Cl2] at various compositions (0.5%, 1%, and 2%). The prepared compounds were characterized with several analytical methods, including X-ray fluorescence (XRF) spectrometry, Fourier-transform infrared spectroscopy (FT-IR), electrospray ionization mass spectrometry (EIS), scanning electron microscope (SEM), X-ray diffraction (XRD), and thermogravimetric-differential thermal (TGA/DTG) analysis. The XRF technique evidenced the presence of Sb metal in the composite beads. FT-IR suggested that the interaction between pectin and the [Sb(TPP)Cl2] complex was assured by inter- and intramolecular C-H⋯O, C-H⋯Cl hydrogen bonds and weak C–H⋯Cg π interactions (Cg is the centroid of the pyrrole and phenyl rings). The morphological features of the prepared polymeric beads were affected by the addition of [Sb(TPP)Cl2] particles, and the surface became rough. The thermal residual mass for the composite beads (29%) was more important than that of plain beads (23%), which confirmed the presence of inorganic matter in the modified polymeric beads. At 20 °C, the highest adsorption amounts of methylene blue were 39 mg/g and 68 mg/g for unmodified pectin and pectin-[Sb(TPP)Cl2] beads, respectively. The adsorption mechanism correlated well with the kinetic equation of the second order and the isotherm of Freundlich. The prepared polymeric beads were characterized as moderate-to-good adsorbents. The calculated thermodynamic parameters demonstrated an exothermic and thermodynamically nonspontaneous mechanism

Crystal structure, Mössbauer spectroscopy and dye adsorption properties of a new layered iron phosphate RbMgFe(PO4)2

Materials based on inorganic phosphates, in particular iron monophosphates, exhibited significant applications in multiple fields due to their structural chemistry. In the present work, the synthesis of a new compound expressed as RbMgFe(PO4)2 was described using flux and solid state methods. The resulting product was analyzed by X-ray diffraction (XRD), Mössbauer and FT-IR spectroscopy and DR UV–vis. It crystallized in the trigonal system (space group P-3m1) with the cell parameters: a = 5.473(2) Å, c = 8.116(3) and Z = 1. Its structure was formed by isolated (Fe, Mg)O4 and PO4 tetrahedra shares vertices to form layers parallel to the ab plane. The Rb+ cations were located in interlayer space. The IR spectrum confirmed the presence of only PO4 group. The distribution of iron and its oxidation state and local environments were confirmed by Mössbauer spectroscopy. The ability of RbMgFe(PO4)2 to adsorb a cationic dye (Methylene Blue) was carried out under the variation of some experimental conditions (pH, concentration, duration and temperature). The adsorption process was chemical and favorable as proved by the data modeling along pseudo second order and both Langmuir and Freundlich theoretical equations

Effective Dyeing of Cotton Fibers Using Cynomorium Coccineum L. Peel Extracts: Study of the Influential Factors Using Surface Response Methodology

The current paper focuses on the use of Cynomorium Coccineum peels extract for cotton fibers dyeing in an easy and effective way without the use of mordants. Prepared extracts were analyzed using UV-visible, FT-IR spectroscopy, Total Contents both Phenolic (TPC) and Flavanoid (TFC) and their ability to reduce reactive species by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging motion experiments. The effect of the most important dyeing conditions, including dyebath pH, temperature, extract concentration, and time contact on the performance of cotton fibers dyeing was discussed. Data were assessed by the measurement of the color strength (K/S). A surface design was adopted to assess the influential factors and the interaction effects of the studied parameters. The optimal conditions for dyeing were to be: pH = 5.5, T = 72.5°C, extract concentration = 0.275% and dyeing duration = 25 min. As also observed, changing the concentration of the electrolyte NaCl, the color strength can be improved. Overall, the friendly extracted dye exhibited excellent textile dyeing characteristics with uniform morphology as proved by SEM analysis and good fastness to washing, perspiration, and rubbing

Sustainable Dyeing of Cotton Fibers Using Aqueous Extract of Citrullus Colocynthis Leaves: Chemical Characterization, and Dyeing Optimization Process Using Response Surface Methodology

Owing to their advantageous characteristics, natural dyes are highly needed to replace hazardous synthetic colored molecules. In this work, an aqueous extract of Citrullus colocynthis leaves was prepared, analyzed using Fourier Transform Infrared (FT-IR) spectroscopy and High-Pressure Liquid Chromatography/Mass Spectrometry (LC-MS/MS), and further used to dye cotton fibers. FT-IR results suggested that the studied Citrullus colocynthis leaf is possibly rich in phenolic and flavonoid constituents. The dyeing experiments were carried out at various experimental conditions: dyeing duration (30–60 min), temperature (60–100°C), and pH (5–9). Response surface methodology (RSM), with the help of Minitab 17.1.0, was used to optimize the dyeing process. The optimum obtained dyeing conditions were time = 30 min, temperature = 91°C, and pH = 7. The cationization of cotton fabric with polyethyleneimine and a co-polymer of dimethyl diallyl ammonium chloride and diallylamin, and the pre-biomordanting with pomegranate peel and date palm pits significantly improved the color strength (K/S) results. Overall, the dyed cotton samples exhibited good fastness characteristics

A Cellulosic Fruit Derived from Nerium oleander Biomaterial: Chemical Characterization and Its Valuable Use in the Biosorption of Methylene Blue in a Batch Mode

Cellulose substrate waste has demonstrated great potential as a biosorbent of pollutants from contaminated water. In this study, Neriumoleander fruit, an agricultural waste biomaterial, was used for the biosorption of methylene blue from synthetic solution. Fourier-transform infrared (FTIR) spectroscopy indicated the presence of the main absorption peak characteristics of cellulose, hemicellulose, and lignin compositions. X-ray diffraction (XRD) pattern exhibited peaks at 2&theta; = 14.9&deg; and 2&theta; = 22&deg;, which are characteristics of cellulose I. Scanning electron microscopy (SEM) showed a rough and heterogeneous surface intercepted by some cavities. Thermogravimetric analysis (TGA) showed more than a thermal decomposition point, suggesting that Nerium fruit is composed of cellulose and noncellulosic matters. The pHpzc value of Nerium surface was experimentally determined to be 6.2. Nerium dosage, pH, contact time, dye concentration, and temperature significantly affected the adsorption capacity. The adsorption capacity reached 259 mg/g at 19 &deg;C. The mean free energy ranged from 74.53 to 84.52 KJ mol&minus;1, suggesting a chemisorption process. Thermodynamic parameters define a chemical, exothermic, and nonspontaneous mechanism. The above data suggest that Nerium fruit can be used as an excellent biomaterial for practical purification of water without the need to impart chemical functionalization on its surface