Preparation of ferromagnetic metal fine fibers by organic gel-thermal reduction process

The organic gel-thermal reduction process was used for the preparation of ferromagnetic metal Ni, Co and Fe fine fibers from the raw materials of citric acid, lactic acid and metal salts. The structure, thermal decomposition process and morphologies of the gel precursors and fibers derived from thermal reduction of these gel precursors were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermo-gravimetric/differential scanning calorimetry and scanning electron microscopy. The results show that spinnability of gel largely depends on molecular structure of metal-carboxylate complex that is a linear-type structure formed in the gel. As a result, the gels exhibit a good spinnability. Metal Ni, Co and Fe fine fibers are featured with diameters of around 1 μm and a high aspect ratio up to 1×106.

Synthesis and Performance of Titanium Organic Gel Doped with Rare Earth

White nano-titanium organic compound-gel with steady performance was synthesized by sol-gel method. This gel has good absorbency to ultraviolet rays. Specially, the absorption wavelength of the organic gel shifted from 250.9 to 254.3 nm(doped with La) and 257.8 nm(doped with Ce), respectively and the absorption peak broadened. The broadening extent has direct ratio with the doping content. It is indicated that when the thickness of the organic gel coat is 60 μm, 98.8% ultraviolet with radiation intensity of 17.2 μW·cm -2 is blocked off. The TEM test shows that the diameter of the titanium organic gel doped with lanthanum is about 5 nm and the granules are uniform. It is indicated that by X-ray this organic substance is amorphous state and it will form nano-TiO_2 with anatase structure calcined at 450 ℃.

One-step synthesis of Cu(Ⅱ) metal–organic gel as recyclable material for rapid, efficient and size selective cationic dyes adsorption

Efficient removal of non-biodegradable and hazardous dyes from wastewater remains a hot research topic.Herein,a rationally designed a Cu(Ⅱ)-based metal–organic gel(Cu-MOG)with a nanoporous 3 D network structure prepared via a simple one-step mixing method was successfully employed for the removal of cationic dyes.The Cu-MOG exhibited high efficiency,with an adsorption capacity of up to 650.32 mg/g,and rapid adsorption efficiency,with the ability to adsorb 80%of Neutral Red within 1 min.The high adsorption efficiency was attributed to its large specific surface area,which enabled it to massively bind cationic dyes through electrostatic interaction,and a nanoporous structure that promoted intra-pore diffusion.Remarkably,the Cu-MOG displayed size-selective adsorption,based on adsorption studies concerning dyes of different sizes as calculated by density functional theory.Additionally,the adsorption performance of the Cu-MOG still maintained removal efficiency of 100%after three regeneration cycles.These results suggested that the Cu-MOG could be expected to be a promising and competitive candidate to conveniently process wastewater.

Synthesis and Characteristics of Organic Bentonite Gel

The bentonite was modified using Ca-bentonite as a matrix and octadecyl/ hexndecyl ammonium chloride as the cover agent, based on hydrothermal process. The organic gel with 5.0 Pa· s viscosity was synthesized by dispersing it into the dimethyl benzene- methyl alcohol system fully. The optimum process conditions for organic modification were that the coating agent dosage is 22g/ L, reaction time is 90 minutes and the pH value of pulp is 10. X-ray diffraction （ XRD ） analysis indicates that the d （001） value of the modified bentonite is 20. 532 A. The influence of gel temperature on its viscosity characteristic was studied. By analyzing the transmssion electron microscopy （TEM） images and observing the dispersed gel, the nanometer effect of the organic gel was discussed.

Preparation of organically functionalized silica gel as adsorbent for copper ion adsorption

A novel adsorbent （AMPS-silica） was synthesized by bounding AMPS （2-acrylamido-2-methylpropanesulfonic acid） onto silica surface, which functioned with γ-methacryloxypropyltrimethoxysilane reagent. The adsorbent was characterized by nitrogen adsorption/desorption measurement, thermogravimetric analysis （TGA） and potentiometric titration analysis. The TGA result indicated that the surface modification reactions introduced some organic functional groups onto the surface of silica. The surface area of AMPSsilica was 389.7 m2/g. The adsorbent was examined for copper ion removal in series of batch adsorption experiments. Results showed that the adsorption of Cu2＋ onto AMPS-silica was pH dependent, and the adsorption capacity increased with increasing pH from 2 to 6. The adsorption kinetics showed that Cu^2＋ adsorption was fast and the data fitted well with a pseudo secondorder kinetic model. The adsorption of Cu^2＋ onto AMPS-silica obeyed both Freundlich and Langmuir isotherms, with r^2 = 0.993 and r^2 = 0.984, respectively. The maximum Cu^2＋ adsorption capacity was 19.9 mg/g. The involved mechanism might be the adsorption through metal binding with organic functional groups such as carboxyl, amino and sulfonic groups. Cu^2＋ loaded on AMPS-silica could be desorbed in HNO3 solution, and the adsorption properties remain stable after three adsorption-desorption cycles.