New Ethylenediamine Crosslinked 2D-Cellulose Adsorbent for Nanoencapsulation Removal of Pb (II) and Cu (II) Heavy Metal Ions: Synthesis, Characterization Application, and RSM-Modeling

The main objective of the present work is to elaborate on a new eco-friendly and efficient adsorbent designated for aquatic micropollutants removal. However, the synthesis of the Ethylenediamine Crosslinked 2D-Cellulose green adsorbent was carried out successfully, by partial grafting of benzyl entities onto hydroxyl groups of HEC, and crosslinking with ethylenediamine ED. Further, the new ethylenediamine crosslinked 2D-Cellulose was used as a biosorbent for nanoencapsulation removal of copper and lead heavy metal ions from aqueous solutions. The proposal chemical structures of unmodified and modified materials were confirmed using FTIR, XRD, TGA, and SEM–EDX analysis. Furthermore, many parameters of the optimization for Pb (II) and Cu (II) in terms of removal efficiency including pH, adsorbent amount, and contact time were optimized by response surface methodology with a Box–Behnken design. Based on the desirability optimization with three factors, the maximal removal was 99.52% and 97.5% for Pb(II) and Cu(II), respectively and was obtained at pH = 5.94, 22.2 mg as the optimal adsorbent amount, and 21.53 min as contact time.

Synthesis and Characterization of TiO2 Nanoparticles Doping on Cellulose as Adsorbent for Removal of Rhodamine B in Aqueous Solution

Cellulose from banana fruit bunch was used as a precursor for doping titanium oxide (TiO2) in producing of TiO2/cellulose adsorbent. Cellulose was obtained by chemical impregnation using potassium hydroxide (KOH) and followed by the hydrothermal process at 250oC for 5 h. The mixture of TiO2 nanoparticles and cellulose was carried out into hydrothermal reactor under de-ionized water and ethanol and heated up to 200oC for 4 h in graphite furnace. Surface morphology analysis showed that the TiO2 clearly immobilized on the surface of cellulose with an increasing roughness of surface and irregular size of porosity. The development of the amorphous to the crystalline phase of TiO2/cellulose was clearly observed by the XRD. The effectiveness of TiO2/cellulose for removal of rhodamine B was investigated from different parameters of adsorption in aqueous solution. Kinetic models were well described by the pseudo-first and second-order with the best correlation coefficient (R2) attributing to the occurrence of chemisorption and physisorption mechanism.

Adsorption behavior of gardenia yellow pigment on embedded spherical cellulose adsorbent

A spherical cellulose adsorbent embedded with black wattle extract (SABW) was prepared and used to adsorb gardenia yellow pigment (GYP). The result revealed that SABW presented excellent adsorption performance to GYP.

Biomass-Based Cellulose Functionalized by Phosphonic Acid with High Selectivity and Capacity for Capturing U(VI) in Aqueous Solution

Uranium could be released into the aquatic ecological environment through various sorts of nuclear-related procedures, which has high toxicity and carcinogenicity even with a trace amount. A novel phosphonic acid functionalized cellulose adsorbent (PVKAP) with a simple synthesis strategy is developed based on pumpkin vine cellulose (PVK) as the substrate material for efficient and selective capturing U(VI). Because of the strong coordination between phosphonic acid groups and U(VI), the adsorption efficiency and adsorption selectivity of modified cellulose to U(VI) are greatly improved. The adsorption behavior follows the Langmuir adsorption model and pseudo-second-order kinetics model. The maximum adsorption capacities (pH = 5, T = 293 K) of PVK and PVKAP obtained from Langmuir isotherm are 57.2 and 714.3 mg∙g−1, and the adsorption equilibrium are reached in 240 and 35 min, respectively. Additionally, PVKAP has a high adsorption selectivity which reached 70.36% for U(VI) in multi-ion condition, and recycling studies have shown that PVKAP has good recyclability. Furthermore, batch adsorption experiments and spectral analysis reveal that the efficient enrichment of U(VI) on PVKAP could mainly attribute to the inner layer complexation. Therefore, this environmentally friendly and simple route prepared PVKAP has good a potential application value for U(VI) enrichment in aqueous media related to nuclear waste.

Sorption materials on the basis of technical cellulose from straw and rice husk

Целлюлоза из плодовых оболочек злаковых культур обладает высокой сорбционной емкостью. Однако относительно короткие волокна затрудняют получение прочного бумажного материала. В то же время целлюлоза из соломы, наоборот, обладает относительно большой длиной волокна и приемлемыми сорбционными свойствами. Для разработки эффективных целлюлозосодержащих сорбентов интерес представляет композиционный материал из целлюлозы шелухи и целлюлозы соломы. Цель исследования – получение сорбционного материала на основе технической целлюлозы из соломы и шелухи риса. Техническая целлюлоза из соломы и шелухи риса получена окислительно-органосольвентным способом с предварительной щелочной обработкой растительного сырья (зольность ее 0,05 % от абсолютно сухой целлюлозы). При этом целлюлозу из соломы риса применяли в качестве целлюлозы-основы, а целлюлозу из шелухи риса – как целлюлозу- адсорбент. При постоянном содержании целлюлозы-основы в композиции независимо от степени ее помола капиллярная впитываемость изменяется в пределах погрешности измерений. При постоянном содержании целлюлозы- основы в композиции и добавлении к ней целлюлозы-адсорбента с возрастающей степенью помола капиллярная впитываемость снижается незначительно (на 1…2,5 мм). Сорбционная способность по йоду зависит от степени помола как целлюлозы-адсорбента, так и целлюлозы-основы. С увеличением степени помола сорбционная способность по йоду возрастает. Адсорбционная способность по метиленовому голубому при постоянном содержании 50% целлюлозы-основы в композиции и добавлении к ней целлюлозы-адсорбента с увеличивающейся степенью помола (35, 39, 43,5, 47,5 оШР) возрастает. Установлено, что количественная оценка эффективности композиции подтвердила наличие эффекта синергизма, который характерен для адсорбционной способности по метиленовому голубому и возрастает с увеличением степени помола целлюлозы- адсорбента с 1,07 до 1,12 с учетом погрешности эксперимента. Cellulose from the fruit shells of cereals has a high sorption capacity. However, relatively short fibers make it difficult to obtain durable paper material. At the same time, straw cellulose, on the contrary, has a relatively long fiber length and acceptable sorption properties. For the development of effective cellulose sorbents of interest is a composite material of cellulose husks and cellulose straw. The aim of the work is to obtain sorption materials on the basis of technical cellulose from straw and rice husks obtained by oxidation-organosolvent method with pre-alkaline treatment of vegetable raw materials. In the course of work, technical cellulose from straw and rice husks with ash content of 0.05% of completely dry cellulose was obtained. Upon receipt of the sorption material, cellulose from rice straw is used as a base cellulose, and cellulose from rice husk as cellulose is an adsorbent. With a constant content of cellulose base in the composition, regardless of its degree of grinding, capillary absorbency varies within the measurement error. With a constant content of cellulose-base in the composition and the addition of cellulose-adsorbent with an increasing degree of grinding capillary absorbency decreases slightly (1...2,5 mm). The sorption capacity of iodine depends on the degree of grinding, as cellulose-adsorbent, and the degree of grinding of cellulose-base. With increasing degree of grinding sorption capacity of iodine increases. Adsorption capacity of methylene blue at a constant content of cellulose-base 50 % in the composition and the addition of cellulose- adsorbent with an increasing degree of grinding (35, 39, 43.5, 47.5 0SHR) increases. It was found that the quantitative evaluation of the composition efficiency confirmed the presence of synergism effect, which is typical for the adsorption capacity of methylene blue and increases with increasing the degree of cellulose-adsorbent grinding from 1.07 to 1.12, taking into account the experimental error.

Batch removal of Pb (ΙΙ) ions from aqueous medium using gamma-Al2O3 nanoparticles/ethyl cellulose adsorbent fabricated via electrospinning method: An equilibrium isotherm and characterization study

The aim of the present work is to study the efficiency of a biocompatible polymer-based adsorbent for the removal of Pb (II) ions whose devastating effects on people’s health is a matter of great concern from aqueous solution. In this study, ethyl cellulose and gamma-Al2O3 nanoparticles/ethyl cellulose electrospun adsorbents were prepared for the batch removal of Pb (II) ions from aqueous solution. Both samples were characterized using contact angle analysis, N2 adsorption/desorption technique, FT-IR and SEM. The Freundlich model (R-square = 0.935 and RMSD (%) = 6.659) and the Dubinin-Radushkevich model (R-square = 0.944 and RMSD (%) = 6.145) were found to be more reliable in predicting the experimental data from the adsorption of Pb (II) ions onto the electrospun gamma-Al2O3 nanoparticles/ethyl cellulose than the Langmuir model (R-square = 0.685 and RMSD (%) = 14.61) and also the Temkin model (R-square = 0.695 and RMSD (%) = 14.38).