Advanced Materials Research Vols. 1033-1034

Abstract: Novel biodegradable cellulose-based hydrogels were synthesized using a non-toxic crosslinker, polyethylene glycol diglycidyl ether (PEGDE). The effects of the crosslinker concentration and the ratio of sodium carboxymethyl cellulose (CMC) to cellulose were investigated. The results indicate that decreasing the amount of PEGDE and increasing the CMC to cellulose ratio resulted in better swelling. The 9:1 CMC/cellulose hydrogel with incorporating 3g of PEGDE had a swelling ratio of 230g/g. The synthesized hydrogels exhibited less swelling in NaCl solution due to a decrease in the osmotic pressure between the interior of the hydrogel network and the external immersion medium.

Abstract: In this work the pyrolysis of waste printed circuit boards (PCBs) were investigated through TG technology and a quartz tube batch reactor, respectively. The TG analysis results showed that the total mass loss from 30-800 ^oC for PCB1 and PCB2 were 35.7% and 41.1%, respectively. With the increase of pyrolysis temperature in a batch reactor, gas yield of PCB2 increased, but increasing rate gradually decreased. The gas yield of PCB2 for pyrolysis time of 1min, 5min and 10min at 600 °C were 30.5%, 31.1% and 31.7%, respectively. It is suggested that the better pyrolysis temperature was at the range of 500-600 °C and the optimal pyrolysis time was 1min. The higher gas yield of PCB2 was obtained at air atmosphere than that at nitrogen atmosphere.

Abstract: Vat dark blue BO simulated wastewater was treated by Dissovled air flolation (DAF), the interaction of sodium dodecyl sulfate (SDS) and precipitate in the DAF process was investigated by thermodynamic methods. The adsorption isotherms of SDS on precipitate at pH 5.00 were determined at 30,35,40 and 45°C. The isosteric heat of sorption was calculated by the Clausius-Clapeyron equation. The results show that the isotherm of SDS on coagulation precipitate is not the normal style, the adsorption of SDS on precipitate is exothermic in nature and the isosteric heat of adsorption decreases with a increase in the equilibrium uptake of SDS on precipitate. The isosteric heat of sorption varies between-16.266 and-21.719kJ/mol as surface loading is between 3 and 11 mg/g. The values of isosteric heat of adsorption proves the primary adsorption of SDS on precipitation is physisorption.

Abstract: Sludge on the ecological environment and human health dangers of long-term potential, the disposal of sludge should focus harmless, resources and energy of. The traditional method of sludge disposal as landfill, incineration, ocean emissions, compared to today's more stringent of environmental standards is clearly inappropriate; currently sludge recycling processes such as pyrolysis oil technology, fuel system technology, thermal Preparation of sorbent technology solutions are better resources and technology, are able to take full advantage of the high organic matter content of the sludge characteristics, not only a way to solve the problem of sludge, also produce a lot of useful material, to achieve waste Po, in line with its sustainable development strategy is conducive to the establishment of recycling economy.

Abstract: In order to achieve sustainable development of the papermaking industry, the papermaking enterprises must devote major efforts to implement cleaner production and cleaner production auditing. Based on the objectives and basic ideas of cleaner production auditing, the article took one papermaking enterprise in Baicheng city of Jilin Province as an example and studied deeply how to implement cleaner production auditing in papermaking enterprise, in order to hold a mirror to papermaking enterprise in cleaner production auditing.

Abstract: the PEG with the molecular weights(MW) ranging from 200 to 2000 have been extensively investigated for Fenton oxidation. The affectingfactors such as pH, dosage of hydrogen peroxide and FeSO4•7H2O was studied in the experiment. The experimental results showed that the dosage of Fenton's reagent ( FeSO4•7H2O was 0.3g/L and 30%H2O2 was 0.5ml/L）was 3:5 and the pH was 3 at the room temperature, the highest CODcr removal ratio can be up to 84%.

Abstract: The effect of several important parameters on the removal of hexavalent chromium by humic acid was evaluated using an optimal experimental design based on Box-Behnken Response Surface method. The factors included temperature、pH、initial potassium chromate concentration and adsorbent dosage. A quadratic model for predicting the optimum removal conditions was derived, and the obtained optimal parameters were temperature 51°C, pH=2.34, initial potassium chromate concentration 14.30mg/L and adsorbent 0.58g. At the optimal conditions, the maximal removal rate of hexavalent chromium reached 73.17 %( forecast value was 73.26%).

Abstract: The effective factor such as temperature, pH, AQS and the content of U(VI) were investigated in the study on removal U(VI) by humic-reducing bacteria (HRB). The analysis of FTIR showed the carboxyl, amide and phosphate groups are the main functional group to remove U(VI), and the optimal temperature is about 30°C, the optimal pH is about 6.0 and the optimal content of AQS is about 1.0 mmol/L.

Abstract: A method of decomposition for tungsten residue using concentrated hydrochloric acid by reflux is presented. The hydrochloric acid concentration, hydrochloric acid consumption and reflux time were investigated. The decomposition of tungsten residue using concentrated hydrochloric acid by reflux was compared to non-reflux. The results show that the reflux method is significantly better than the non-reflux method. The optimum decomposition conditions for tungsten residue are that the hydrochloric acid consumption is at 38.55 mmol/g and the mixture of concentrated hydrochloric acid and tungsten residue are heated to reflux under stirring for 4 h. The decomposition ratio is Fe 98.88%, Mn 98.63%, RE 99.13%, Sc 98.78%, Th 97.84%, Ti 97.11%, U 96.92%, Zr 95.76%, Nb 6.65%, Ta 3.54%, and W 0.89%.

Abstract: NaY zeolite was prepared by a simple sol-gel process. The prepared NaY was characterized by XRD,FT-IR,N₂ adsorption/desorption isotherms, and scanning electron microscope (SEM). The CO₂ dynamic adsorption/desorption performance of NaY was tested under atmospheric pressure using adsorption curve method in the fixed bed. The results demonstrate that NaY offeres high separation efficiency for CO₂ against N₂. To further identify the most adsorption conditions, different adsorption temperatures and gas flow rates were investigated respectively. It is shown that NaY zeolite has the largest adsorption capacity of 88 mg/g adsorbent at 60°C,50ml/min, and the sample maintains still strong adsorption capacity and stable structure during 6 consecutive test cycles, which exhibits its stable adsorption/desorption behavior.