Applied Mechanics and Materials Vols. 295-298

Abstract: Adopted the treatment methods of ultrasonic dispersion on nano-TiO2/Al2O3, of sustained-releasing ClO2 and of post-heating way. The results show that the reduction rate of formaldehyde emission treated by nano-TiO2/Al2O3 is 22.2%, the average reduction rate of particleboard free formaldehyde in nine days is 64.7%, and the post-heating- treatment can reduce the plywood formaldehyde by 34.5%.

Abstract: The objective of this paper is to investigate the feasibility of phenol adsorption from aqueous solution by Pinus massoniana biochar. Adsorption conditions, including contact time, initial phenol concentration, adsorbent dosage, strength of salt ions and pH, have been investigated by batch experiments. Equilibrium can be reached in 24 h for phenol from 50 to 250 mg• L^-1. The optimum pH value for this kind of biochar is 5.0. The amount of phenol adsorbed per unit decreases with the increase in adsorbent dosage. The existence of salt ions makes negligible influence on the equilibrium adsorption capacity. The experimental data is analyzed by the Freundlich and Langmuir isotherm models. Equilibrium data fits well to the Freundlich model. Adsorption kinetics models are deduced and the pseudo-second-order kinetic model provides a good correlation for the adsorbent process. The results show that the Pinus massoniana biochar can be utilized as an effective adsorption material for the removal of phenol from aqueous solution.

Abstract: In the present investigation, lab-made mesoporous activated carbon (MAC) was prepared for testing the ability to remove Cr(VI) from aqueous solution. The influences of several operating parameters such as pH and temperature on the adsorption were investigated. Solution pH is found highly influencing the adsorption and low pH is favorable for Cr(VI) adsorption. The adsorption of Cr(VI) is enhanced with increased temperature. Thermodynamic parameters were evaluated and the adsorption was endothermic. Several adsorption isotherms include Langmuir, Freundlich and Dubinin–Radushkevich(D–R) were used to fit the equilibrium data. The adsorption kinetic data of Cr(VI) were analyzed and was found fitting well in pseudo-second order equation. The lab-made MAC is found to be effective adsorbent for removal of Cr(VI) from aqueous solutions.

Abstract: Chromaticity of cigarette industry wastewater increase when treating by aerobic due to large quantities of lignin, nicotine and carbohydrate. Ozone and advance oxidation are proposed for degradation and decoloration of cigarette wastewater that processed by aerobic. The result shows that ozone process has its advantage of high decoloration rate, simple operation and low operation cost. Optimum parameters of ozone process are ozone dosage of 37.65mg/L, reaction time of 15min, reaction pH of 7.0-9.0. The COD removal rate is 38.3% when the decoloration rate is 57.5%. Operation cost of ozone process is 0.4 yuan/m³.

Abstract: An experiment on seepage and purification by modified mixtures of power plant fly ash and soil at different mass ratios was studied for developing a novel high efficient substrate of constructed wetland. The results showed that the soil’s osmotic coefficient can be improved by mixing fly ash and soil. The different mass mixing ratios of ash and soil had little effects on the removal of total nitrogen in wastewater, comparatively they had positive effects on the removal of total phosphorus and ammonia nitrogen. The phosphorus’s removal efficiencies were maintained at 81.94%~89.68%. The average removal efficiency of ammonia nitrogen was 85%, and the 4:6 level obtained the best removal efficiency, which was 93.41%. The different mass mixing ratios of ash and soil had obvious effects on COD removal of wastewater. The 1:9 and 0:10 levels gained higher removal efficiencies than others, whose removal efficiencies were 95.16% and 95.39%, respectively.

Abstract: Fenton’s reagent method optimizes conventional wastewater oxidization treatment technologies to remove biodegradable organic matter that cannot be removed. In this paper, ferric chloride hexahydrate, iron (II) chloride tetra hydrate, and ammonia act as raw materials in preparing the nano-iron oxide / polymer composite material ferric chloride. Self-made composite treatment of phenolic wastewater in the reaction time 120min,0.076mol/mL composite dosage 3ml (concentration), H2O2 concentration of 15% (dosage), Fe2 + / Fe3 + ratio of 2:1 for phenol removal of the best wastewater.

Abstract: Studies the effects of potassium ferrate combined with powdered activated carbon (PAC) to deal with the trace organics in water. It found that powder activated carbon (PAC) can adsorb the suspended solids produced by potassium ferrate removing pollutants generated in water, reduce turbidity and color result in potassium ferrate oxidation process, and remove a small amount of organics in the same time.

Abstract: Experimental wastewater generated in the process of preparation catalyst for the production of acrylamide, it containing a large number of sub-phosphate, sulfate. As a starting point to reduce total phosphorus concentration (TP = 2300mg/L), determine conditions to examine such as the best precipitant agent and its dosage, reaction pH, temperature and other single-factor conditions. After extensive tests confirmed, 100ml of this phosphorus-containing wastewater was adjusted to pH 8, at 30 °C, 3.0g of calcium chloride was added, reaction 180min, total phosphorus concentration can be reduced to 200mg/L or less, phosphorus removal rate can reach 91%. XRD, TG-DTA characterization analysis showed that the main component of chemical deposits were calcium phosphate and calcium sulfate crystals

Abstract: This Experiment study on the simultaneous degradation effect of Cu(II) and Cr(Ⅵ) in the micro-polluted water by potassium ferrate. And the influential elements on the removal effects and probed into the degradation mechanism was analyzed. The results indicated that the removal rates of Cu(II),Cr(Ⅵ) by synergetic effect of potassium ferrate oxidation and coagulation were 76.2%、62.2%,respectively,when the optimizing conditions were as follows: oxidation pH was 7,oxidation time was 20min,flocculation pH was 9,flocculation time was 30min and dosage of potassium ferrate was 40mg/L.

Abstract: Solution of phosphoric acid was used to bond TiO₂, investigating the effect of adhesive proportion, calcination time, calcination temperature in the process of the preparation. The representation of catalyst was characterized by means of X-ray diffraction (XRD), surface detection system (BET) and scanning electron microscopy (SEM). Results showed that when the drying temperature was at 106°C, calcination temperature was at 800°C and a calcination time was 4h, the catalyst carrier TiO₂ was in the form of anatase structure with XRD characterization.