Advanced Materials Research Vols. 455-456

Abstract: Using the three-layer impellers with big size diameter in an unbaffled elliptic bottom stirred tank，the gas holdup (ε) was studied in the systems of air-polyether polyol (PPG). The results indicate that the gas holdup in the air-PPG system is higher, it increase with the superficial gas phase velocity (V_s) and specific power input (P_m) increase, and decrease as the temperature increase. The influence is severely when the temperature is below 100°C, and is weak above 100 °C.The conclusions give reference for choosing the operation parameter and designing and scale-up of PPG polymerization reactor.

Abstract: For the lacks of magnesium-based desulfurizer in iron and steel industry, this paper investigated thermodynamics calculation of a new desulfurizer, MgO based desulphurizer. The results indicate that the beginning reaction temperature of light-burned dolomite and Al is 1314°C, the beginning reaction temperature of light-burned dolomite and Si is 1565°C, the beginning reaction temperature of MgO and Al is 1475°C, and the beginning reaction temperature of MgO and C is 1846°C. The reaction temperature between MgO and C is too high, so the carbon-thermal reduction can’t occur easier. When the hot iron temperature is 1400°C and the addition of alumnium and iron oxide is 12.77%, the reaction between MgO and C will be induced.

Abstract: Co²⁺-doped ZnO/ZnAl₂O₄ composite films have been prepared by facile calcination of a single-source Co^IIZn^IIAl^III-layered double hydroxide (Co^IIZn^IIAl^III-LDH) precursor. The preparation was performed initially by cast aqueous precursor slurry on quartz glass substrate and subsequent transformation to a network-like film via calcination. The surface morphology and composition of the resulting films were characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), and XPS analyses. The results clearly indicated that the as-deposited film is composed of Co²⁺-doped ZnO and ZnAl₂O₄, and also large ZnO single crystals are homogeneously incorporated into small ZnAl₂O₄ particle matrix. The influence of Co²⁺-doping concentration on microstructure and also on optical properties of the composite films was also investigated.

Abstract: In this paper, a method for simultaneous determination of Si, Mn, P, Cr, Ni, Mo, Nb, V, Ti, Cu and Al in high grade pipeline steel by inductively coupled plasma atomic emission spectrometry (ICP-AES) has been proposed. The experiment factors such as the preparation of the sample solution, the selection of the analytical lines for every element and the instrument parameters have been investigated. The method has been approved as a convenient and rapid method with good precision and accuracy.

Abstract: The Response Surface Analysis using the BBD (Box-Behnken Design) design (Design Expert, Cabit Information Technology Co., Ltd) was applied in identifying the optimal process parameters for the separation and purification of fennel oil using molecular distillation technology. The experiments were carried out based on single factor analysis (feeding rate, evaporation temperature and film wiping speed). The dependent variable second-order regression equation was obtained. The optimal conditions were identified as: feeding rate = 2 drops/second, evaporation temperature = 50°C and film wiping speed = 215 rpm. The concentration of anisole in the extraction under the optimized condition reached 86.69%.

Abstract: The recycling conditions of lead and zinc from gold and silver tailings by wet processing are as follows: leaching in confined condition and liquid to solid ratio of 5, at 90 ∽ 950C, for 4h, using NaCl (300g / L), CaCl2 (105% of theoretical amount), the acidity is 130% theoretical amount and the granularity is 300 mesh size; sponge lead can be obtained by using reduced iron (110% of theoretical amount) at 75∽850C for 3h; iron and zinc can be separated from hydrochloric acid system by TBP and then used for the preparation of the corresponding products; all the mother liquor can be recycled and the consumption amount of raw materials is low because there is no need for additional sodium chloride in the cycling. This processing method has better economic and environmental benefits.

Abstract: Acrylonitrile-Butadiene-Styrene (ABS)/CaCO₃ composites were reprocessed under normal conditions. The effects of reprocessing on the degradation of ABS were investigated by Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). The mechanical properties of the reprocessed materials were measured. In this paper, a method to evaluate the degradation of ABS in ABS/CaCO₃ composites by FTIR was described. The results show that within the range of the reprocessing cycles studied, as the number of reprocessing cycles increased, the impact strength of composite was significantly reduced if the content of CaCO₃ is lower than 10%, due to the degradation of rubber phase. However, the impact strength was almost unchanged when the content of CaCO₃ was higher than 15%.

Abstract: A fatty acid-starch complex was prepared to apply in the linerboard surface treatment (sizing). Compared with the raw corn starch and commercial size press cationic starch, the fatty acid-starch complex displayed better water resistance, higher tensile strength and higher bending stiffness of treated samples. Two different fatty acids of C16 like palmitic acid and C18 like stearic acid were compared. Both C16 and C18 fatty acids showed similar results. Small amount of clay addition to the complex could increase the tensile strength and bending stiffness of sized samples, while keeping the good water resistance. PCC also could increase the tensile strength with the small amount of addition to the fatty acid-starch complex as surface sizing agent in our study. The SEM pictures of surface treated samples using the complex with and without clay and PCC were taken and the bonding characteristics and surface film formation were investigated.

Abstract: To reduce the production cost of polyhydroxyalkanoates (PHA) and disposal amount of excess sludge simultaneously, volatile fatty acids (VFAs) from alkaline excess sludge fermentation was used as carbon sources to synthesize PHA by unenriched mixed cultures. Released phosphorus and residual ammonium in the fermentative VFAs was controlled by adding magnesium to form struvite precipitation. Four VFAs liquids obtained was used to test the influence of initial carbon load and carbon to nitrogen ratio (C:N ratio) on the VFAs uptake rate, PHA storage rate and biomass growth rate. Results show that higher initial carbon substrate load results in relatively higher VFAs uptake rate and higher PHA storage rate, while higher initial C:N ratio results in relatively lower biomass growth rate from VFAs. VFAs generated from thermophilic alkaline sludge fermentation were a suitable carbon source for PHA production by mixed cultures.

Abstract: Two different extraction methods, microwave extraction and traditional soxhlet extraction, were used to evaluate the optimal extraction process of coal for direct carbon fuel cells through enrichment efficiency of the organic components and extraction time required under the same extraction rate. The experimental results showed that the extraction rate of microwave extraction was 9.7368% when adopted tectonic coal of 8th coal mine as sample, selected 80mL pyridine as solvent, set 95W as microwave power and 3min as extraction time. Under the same extraction rate condition, soxhlet extraction time is 35.73h, and the extraction efficiency of the microwave extraction was 714.6 times that of the soxhlet extraction. The microwave extraction was a simplify and promising working for coal, which was used as raw fuel for direct carbon fuel cells, with fast extraction speed, large sample capacity, energy saving and environmental friendly.