查找使用阿拉丁产品的科研文献

Surface functionalized natural inorganic nanorod for highly efficient cellulase immobilization

Chao Yang,Haodao Mo,Limin Zang,Jian Chen,Zhenqiang Wang,Jianhui Qiu

An attapulgite@chitosan (ATP@CS) nanocomposite was prepared by coating chitosan onto naturally needle-like nanoscale attapulgite clay. The nanocomposite was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis. Cellulase was covalently immobilized on this ATP@CS support using glutaraldehyde activation method and compared to (3-aminopropyl) triethoxysilane modified ATP (ATP–APTES) support. The amount of cellulase on the ATP@CS and ATP–APTES was 88.3 and 76.5 mg g−1, respectively. The reusability and effects of pH and temperature on activity were studied. The ATP@CS immobilized cellulase exhibited higher pH and thermal stability as well as good reusability compared to the ATP–APTES immobilized cellulase and the free cellulase. The immobilized cellulase samples were also utilized to hydrolyze wheat straw to evaluate their potentially practical applications.

Production of three-dimensional porous polydopamine-functionalized attapulgite/chitosan aerogel for uranium(VI) adsorption

Liao Yun,Wang Meng,Chen Dajun

A novel three-dimensional porous polydopamine-functionalized attapulgite/chitosan (AT@PDA/CS) aerogel was designed and prepared for uranium(VI) adsorption, and its morphology and structure were characterized by TEM, SEM-EDS, XRD, FT-IR, Raman and XPS techniques. According to batch experiments, its adsorption equilibrium was reached within 40 min at pH 5.0. The adsorption isotherms was fitted well for Langmuir isotherm model and maximum adsorption capacity was 175.1 mg g −1 at 328 K. The thermodynamic analysis indicated that the adsorption was an endothermic and spontaneous process. Furthermore, the aerogel has superior absorption reusability and the removal efficiency was maintained at 78% after five adsorption–desorption cycles.

Multifunctional honeysuckle extract/attapulgite/chitosan composite films containing natural carbon dots for intelligent food packaging

Wenting Gao,Bin Mu,Fangfang Yang,Yalong Li,Xiaomei Wang,Aiqin Wang

In order to fulfill people's requirements for food quality and safety, it is a promising strategy to develop intelligent biodegradable food packaging materials. Herein, honeysuckle extracts/attapulgite/chitosan composite films containing natural carbon dots were fabricated for intelligent food packaging. Different characterization techniques were employed to study the obtained composite films, while the physicochemical properties, optical properties, antibacterial and antioxidant activities of composite films were determined. The obtained composite films presented good mechanical, antibacterial and antioxidant properties, and the antibacterial ratios of composite films against Escherichia coli and Staphylococcus aureus were 99.27 ± 0.18 % and 98.85 ± 0.65 %, respectively. When the added amount of honeysuckle extracts/attapulgite nanocomposites was 4.76 %, the tensile strength and elongation at break of composite films reached 24.9 ± 2.35 MPa and 64.8 ± 2.11 %, respectively, which were obviously higher than that of pure chitosan film. Furthermore, the composite films exhibited excellent UV shielding and blue fluorescence properties, as well as pH-sensitivity due to the presence of caffeoquinic acid-based natural carbon dots derived from honeysuckle extract. Therefore, the composite films indicated a potential application for intelligent food packaging.

Flocculation synergistic with nano zero-valent iron augmented attapulgite @ chitosan as Fenton-like catalyst for the treatment of landfill leachate

Yongyao Xu,Wangqing Shen

Preparation of EDTA-modified magnetic attapulgite chitosan gel bead adsorbent for the removal of Cu(II), Pb(II), and Ni(II)

Ping Sun,Wei Zhang,Binze Zou,Lincheng Zhou,Zhengfang Ye,Quanlin Zhao

Attapulgite (ATP) has a unique porous layered chain structure and is an excellent environment-friendly decolorizer. However, its high viscosity makes it difficult to separate. First, it was combined with magnetic Fe 3 O 4 nanoparticles to obtain Fe 3 O 4 -ATP that is easy to recycle and reuse. Then, Fe 3 O 4 -ATP nanoparticles were embedded in chitosan (CS) gel beads, and glutaraldehyde was used for cross-linking and curing. Lastly, ethylenediaminetetraacetic acid (EDTA) was successfully connected to Fe 3 O 4 -ATP/CS gel beads through amidation reaction, which further increased the capability of the adsorbent to adsorb heavy metal ions. The prepared magnetic composite adsorbent is a sphere with a rough surface and porous structure. The maximum adsorption capacity of the prepared Fe 3 O 4 -ATP/EDTA/CS adsorbent for Pb(II), Cu(II), and Ni(II) is 368.32, 267.94, and 220.31 mg g −1 , respectively. After 5 times of repeated use, Fe 3 O 4 -ATP/EDTA/CS still showed good adsorption capacity for Cu(II), Pb(II), and Ni(II). Fe 3 O 4 -ATP/EDTA/CS has a large adsorption capacity for heavy metal ions, a wide pH applicability, good reuse, and rapid magnetic separation. In addition, Cu(II) loaded Fe 3 O 4 -ATP/EDTA/CS also showed good catalytic degradation performance for bisphenol A. This study prepared a new type of adsorbent with good adsorption performance and provided a promising method for the treatment of wastewater.

Efficient adsorption of Pb(II) from aqueous solutions using aminopropyltriethoxysilane-modified magnetic attapulgite@chitosan (APTS-Fe3O4/APT@CS) composite hydrogel beads

Xue Xue Liang,Xiao-Kun Ouyang,Songyan Wang,Li-Ye Yang,Fangfang Huang,Chao Ji,Xiaohong Chen

The performance of Fe 3 O 4 /attapulgite (APT) nanoparticles in Pb(II) adsorption from aqueous solutions could be improved by modifying the particles with aminopropyltriethoxysilane (APTS) and then combining with chitosan (CS) into beads. After preparing the APTS-Fe 3 O 4 /APT@CS beads, their surface morphology and crystal phases were analyzed by Fourier-transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. The magnetic properties of APTS-Fe 3 O 4 /APT@CS were studied by a vibrating sample magnetometer, while their heat resistance and stability were characterized by thermal weight analysis. A recycling test and comparison of adsorption capacities were also carried out. The adsorption capacity of Fe 3 O 4 /APT was improved by the modification with APTS and CS. The adsorption process conforms to the pseudo-second-order kinetic and Langmuir adsorption isotherm models. The adsorption of Pb(II) reaches a maximum of 625.34 mg/g, which compares favorably with other reported adsorbents. The results show that APTS-Fe 3 O 4 /APT@CS is a promising hybrid adsorbent for effective removal of Pb(II) from water.