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According to the World Health Organization, nearly a billion people do not have incoming to pure drinking water and much of that water is contaminated with high levels of heavy elements. In this study, adsorption of lead ions has been studied by nanocomposites which prepared through acrylic acid grafting and amino-functionalized magnetized (FM-NPs) TEMPO-oxidized cellulose nanofiber (TEMPO-CNF). The amino-functionalized magnetite was acting as a crosslinked. The crystallinity of TEMPO-CNF was 75 with a 4-10 nm diameter range, while the average particle size of FM-NPs was 30 nm. The adsorption studies illustrated that the elimination efficiency of lead ions was 80% by the prepared nanocomposite that includes a minimum amount of crosslinker (1%), which demonstrated that the magnetic grafted oxidized cellulose nanofiber nanocomposite is a promising green adsorbent material to eliminate heavy metal ions and is additionally easy to get rid of due to its magnetic property. The kinetics and isotherms studied found that the sorption reaction follows a pseudo-second-order model (R 2  = 0.997) and Freundlich model (R 2  = 0.993), respectively, this indicated that the adsorption of lead ion occurs within the pores and via the functional groups present on the nanocomposite., Competing Interests: Declaration of competing interest The authors declare that they have no conflict with interests., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this experiment, sodium carboxymethyl cellulose (CMC) was used as raw material, rare earth chloride was used as inorganic nano luminescent material to prepare a series of lanthanide rare earth ions-doped composite materials. The photoluminescent materials were prepared via in-situ chemical deposition of rare earth ions onto CMC surface with the help of carboxyl groups contained on the surface of CMC. The structure, fluorescence properties, surface morphology, surface elements, crystalline structure and thermal stability of CMC before and after surface modification were characterized by FT-IR spectra (FTIR), photoluminescence spectra (PL), field emission scanning electron microscope (FESEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and thermal gravimetric analyses (TGA), respectively. The results showed that CMC/LaF 3 :Eu 3+ composites were successfully prepared, and the fluorescence intensity can be organically controlled by the reaction temperature, doping ratio and doping concentration of rare earth ions. The method has mild reaction conditions, facile process without expensive material equipment. Moreover, the as-prepared transparent anti-counterfeiting film possessed good fluorescence intensity, transparency and excellent mechanical properties, which can be used for large-scale functional packaging films., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this work, silanized and aminated lignin (SAL) was synthesized in one step and its adsorption of Congo red and Cu(II) ions in aqueous solution was explored. Lignin was subjected to amine-silanization with (3-aminopropyl) triethoxysilane (APTES). Structural characterization substantiated successful amine-silanzation of lignin and formation of multi-layer APTES intermolecular crosslinked structure. The prepared SAL (nitrogen content = 6.1%) exhibited enhanced molecular weight, thermal stability, and water- and organic solvent-resistance properties. Additionally, the present of the porous structure of particle surface and an increase in the specific surface area and zeta potential promoted the accessibility of contaminants to the effective adsorption sites of SAL. Adsorption experiments showed that both Congo red and Cu(II) ion could be completely removed at original pH value, and their adsorption involved electrostatic attraction and complexation, respectively. The adsorption isotherms and kinetics were well described by the Langmuir and pseudo-second-order equations, respectively. The results showed that SAL is a promising adsorbent for the treatment of effluents., (Copyright © 2020 Elsevier B.V. All rights reserved.)

2,3,6‑Tricarboxy cellulose nanofiber (TPC-CNFs) was prepared by 2,2,6,6-tetramethylpiperidine‑1‑oxyl (TEMPO) oxidation of dissolving cellulose pulp (selective at C-6) followed by periodate-chlorite oxidation (selective on C-2 and C-3). Characterization of the prepared samples were carried out using, atomic force microscope (AFM), carboxylate content determination, FTIR spectroscopy, X-ray diffraction and light transmittance spectra. Also, the mechanical properties of TEMPO-oxidized of cellulose nanofiber (T-CNFs) and TPC-CNFs with and without polyamide-amine-epichlorohydrin crosslinker (PAE) films were determined which the tensile strength were 8.19, 12.43 and 20.5 MPa and elastic moduli of 1814, 1097 and 1150 MPa respectively. Tricaboxy cellulose nanofiber was developed as a novel adsorbent of heavy metal ions. Removal of heavy metals such as Cu 2+ , Ca 2+ and Pb 2+ from aqueous solution was carried out and the adsorption efficiencies were analyzed. On the other hand, the effect of the addition of the crosslinking agent to CNFs and the carboxylate contents of CNFs were investigated., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Contamination of heavy metal in wastewater has caused great concerns on human life and health. Developing an efficient material to eliminate the heavy metal ions has been a popular topic in recent years. In this work, sulfonated cellulose (SC) was explored as efficient adsorbent for metal ions in solution. Thermo gravimetric analyzer (TGA), X-ray diffraction (XRD) and Fourier-transform infrared spectrometer (FTIR) first analyzed the characterizations of SC. Subsequently, effects of solution pH, adsorbent loading, temperature and initial metal ion concentration on adsorption performance were investigated. The results showed that sulfonated modification of cellulose could decrease the crystallinity and thermostability of cellulose. Due to its excellent performance of adsorption to metal ions, SC could reach adsorption equilibrium status within as short as 2min. In multi-component solution, SC can orderly removes Fe(3+), Pb(2+) and Cu(2+) with excellent selectivity and high efficiency. In addition, SC is a kind of green and renewable adsorbent because it can be easily regenerated by treatment with acid or chelating liquors. The mechanism study shows that the sulfonic group play a major role in the adsorption process., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Pretreatment of lignocelluloses is a key step in the biorefinery for production of biofuels and valuable platform chemicals. In this work, various lignocelluloses were pretreated using cholinium ionic liquids (ILs) that are wholly composed of biomaterials, and fractionated into carbohydrate-rich materials (CRMs) and lignin-rich materials (LRMs). Cholinium ILs were found to be effective pretreatment solvents for grass lignocelluloses as well as eucalyptus, resulting in significant improvements in the glucose yields (58-75%) in subsequent enzymatic hydrolysis, while they were inefficient to make pine susceptible to biodegradation. Approximately 46% of lignin in native rice straw was fractionated as LRM after pretreatment using cholinium argininate ([Ch][Arg]). [Ch][Arg] showed excellent recyclability, and the total recovery was as high as 75% after reused for 8 cycles. Besides, rice straw pretreated by the recycled IL remained highly digestible, and good glucose yields (63-75%) were achieved after its enzymatic hydrolysis., (Copyright © 2015 Elsevier Ltd. All rights reserved.)