Shuhua Wang

Functional porous carbons from waste cotton fabrics for dyeing wastewater purification

A new functional porous carbons (PC-WF) is prepared by activation-pyrolysis method use waste cotton fabrics (WF) as an abundant, cheap and available precursor for removal of Brilliant Crocein (BC-GR) and Cationic Red 2GL (CR-GL) from aqueous phase. The PC-WF was characterized by BET, FTIR, SEM, and XRD techniques, the surface area, total pore volume, average pore diameter was found as 1463.5 m2 g-1, 0.783 cm3 g-1 and 2.14 nm, respectively. The influences on BC-GR and CR-GL adsorption of various experimental factors such as initial concentration and temperature were investigated. Adsorption kinetics was found to be best represented by the pseudo-second order model. The adsorption capacity was 319.8 mg g-1 for BC-GR and 842.5 mg g-1 for CR-GL at 30 °C, respectively. The results indicate that for waste cotton fabrics in particular, the practical application of this process to the production of porous carbon would be possible.

Study on converting cotton pulp fiber into carbonaceous microspheres

Carbonaceous materials were produced by means of the hydrothermal carbonization of cotton pulp fiber at temperatures in the 245–305 °C range. The morphology, chemical and structural characteristics of the hydrothermally carbonized products were investigated with scanning electron microscopy (SEM), X-ray diffraction, Fourier-transform Infrared Spectrometer (FTIR) and X-ray photoelectron spectroscopy (XPS). The hydrothermal product of cotton pulp fiber is made up of carbonaceous microspheres (size: 3–8 µm). The carbonaceous microspheres have different chemical structure with one of cotton pulp fiber and have amorphous structure. The surface of carbonaceous microspheres contains a high concentration of reactive oxygen groups.

Strengthening-toughening of Ceramics by Metal Elements Recovered from Electroplating Sludge

Co-precipitation compound precursors-hydrothermal processing was employed to synthesize Ni/Cu/Al2O3/ZrO2 composite powder, and ZrO2-based composite ceramics was prepared. The technology recycled the metal of nickel, copper and aluminum from sludge, and the recovery rate of nickel was up to 95.5%. The property of ZrO2-based composite ceramics was improved because of the existence of nickel and copper particles. The fracture toughness of Ni/Cu/Al2O3/ZrO2 composite ceramics was 8.52 MPa·m1/2 and the compressive strength was 51 MPa, showing the increase by 2.54 times and 1.5 times, respectively, compared with those of pure ZrO2 ceramics.

Preparation and properties of nano-SiO2-coated wool fibers

Nano-SiO2-coated wool fibers were prepared by coating nano SiO2 onto wool fibers pretreated by low-temperature plasma (LTP) irradiation. The morphologies and structures of coated wool fibers were characterized by scanning electron microscopy, transmission electron microscopy, and fourier transformation infrared spectrometry. The results show that after LTP irradiation, the surface structure of wool fibers was changed and new chemical bonds were formed; nano-SiO2 combined well with the wool fibers and formed a functional layer on the surface of wool fibers. Compared with parent wool, the coated wool fibers had better thermal stability, breaking strength, elongation, and frictional property.

The study on the generation of porous carbonaceous microspheres from waste cotton fabric

Abstract In this study, the porous carbonaceous microspheres (PCMs) were prepared using waste cotton fibers as precursor. The cotton fibers were first hydrolyzed and pre-carbonized through hydrothermal process, and then were heat treated at 900 °C. ZnCl2 was used to as catalyst to promote the hydrolysis of waste cotton in hydrothermal process and as pore-forming agent in subsequent heat treatment. The pore structure of the prepared PCMs were evaluated by nitrogen adsorption/desorption test, Fourier Transform Infrared spectroscopy analysis and X-ray photo-electron spectroscopy were conducted to determine its chemical properties. Scanning electron microscope was used to observe its surface morphology. Furthermore, the formation process of PCMs is investigated.