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The goal of this study is to assess Ziziphus lotus's potential for producing carboxymethylcellulose adsorption membranes with the ability to adsorb methyl green from wastewaters by the revalorization of its cellulosic fraction. The cellulose from this feedstock was extracted by an alkaline process and TAPPI standard technique T 203 cm-99 and afterwards they were carboxymethylated. The obtained carboxymethylcelluloses were deeply characterized, being observed that the carboxymethylcellulose produced from the alkaline cellulose presented the higher solubility due to its lower crystallinity degree (53.31 vs. 59.4%) and its higher substitution degree (0.85 vs. 0.74). This carboxymethylcellulose was cross-linked with citric acid in an aqueous treatment in order to form an adsorption membrane. The citric acid provided rigidity to the membrane and although it was hydrophilic it was not soluble in water. By evaluating the potential of the produced membrane for the removal of pollutant dyes from wastewater, it was observed that the adsorption membrane prepared from the carboxymethylcellulose's produced from the Ziziphus lotus was able to remove 99% of the dye, methyl green, present in the wastewater. Thus, this work demonstrates the potential of the Ziziphus lotus for the production of a novel and cost-effective carboxymethylcellulose adsorption membrane with high capacity to treat wastewaters. [ABSTRACT FROM AUTHOR]

Schinus molle (SM) was investigated as a primary source of cellulose with the aim of discovering resources to generate cellulose nanofibers (CNF). The SM was put through a soda pulping process to purify the cellulose, and then, the fiber was treated with an enzymatic treatment. Then, a twin-screw extruder and/or masuko were utilized to help with fiber delamination during the nanofibrillation process. After the enzymatic treatment, the twin-screw extruder and masuko treatment give a yield of 49.6 and 50.2%, respectively. The optical and atomic force microscopy, morfi, and polymerization degrees of prepared cellulosic materials were established. The pulp fibers, collected following each treatment stage, demonstrated that fiber characteristics such as length and crystallinity varied according to the used treatment (mechanical or enzymatic treatment). Obviously, the enzymic treatment resulted in shorter fibers and an increased degree of polymerization. However, the CNF obtained after enzymatic and extrusion treatment was achieved, and it gave 19 nm as the arithmetic width and a Young's modulus of 8.63 GPa. [ABSTRACT FROM AUTHOR]

This study emphasized the efficiency of unconventional delignification treatment "Acetocell" as a basic pretreatment to isolate cellulose fiber from Tamarix aphylla 's stem. Chemical proprieties of obtained cellulose were determined and its efficiency for cadmium ions adsorption was evaluated subsequently. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis, thermogravimetric analysis (TGA), Scanning Electron Microscopy (SEM), fluorescence microscope and Morfi were used to analyze the thermochemical and morphological characteristics of the fibers before and after treatment. Cellulose was used as a biosorbent to remove cadmium ions from polluted water. The effects of many parameters on the efficiency removal of cadmium were investigated; the amount of cellulose, the contact time, pH and the initial concentration of cadmium ions. The optimum conditions were 45 mg of adsorbent, 45 mg L−1, 1200 min and pH 8 which provide best adsorption capacity equal to 44.21 mg g−1. The energy value E = 6.65 kJ mol−l which confirm the physical interaction between cellulose-cadmium ions. Then Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models were followed for modeling adsorption. Langmuir isotherm and the pseudo-second order model seems the most suitable which describe better the adsorption of cadmium ions with best R2 values which equal to 0.9937 and 0.9979, respectively. [ABSTRACT FROM AUTHOR]

Four plants species namely Astragalus armatus , Retama raetam , Pituranthos chloranthus and Nitraria retusa were collected from Kasserine (Tunisia) to study their suitability for pulp and papermaking. Their chemical composition revealed that the α-cellulose content in R. raetam was lower than the normal range of hardwood, but the others were acceptable for pulp production. The Klason lignin content in these species was lower than 20%, except for N. retusa (26%). The amount of extractives in organic solvents was quite high (close to 10%) in R. reatam and P. chloranthus . The previous raw materials were pulped by using the soda-anthraquinone cooking process, the morphological properties, kappa number and the degree of polymerisation of the pulps obtained were determined. Finally, laboratory handmade standard sheets were prepared from the unrefined pulps of P. chloranthus and A. armatus . Their characterisation showed that the prepared papers present low density values and quite good mechanical properties particularly for the unbleached pulp. This study demonstrates the high potentiality of these two species for papermaking applications. [ABSTRACT FROM AUTHOR]