Advanced Materials Research Vols. 781-784

Abstract: Commercial crude tea saponin as raw material, the effect of ultrasonic technology on tea saponin extraction was investigated. Ethanol was selected as the suitable extraction solvent. The six single factors including ethanol concentration, solid-liquid ratio, ultrasonic time, ultrasonic power, ultrasonic frequency and ultrasonic extraction temperature were studied. The four factors of ethanol concentration, solid-liquid ratio, ultrasonic time, ultrasonic temperature were mainly studied by designing orthogonal experimental. The results show that tea saponin content increases from 48.57% to 90.21% under optimum conditions of ethanol concentration 90% (mL/mL), ultrasonic extraction temperature 40 °C, solid-liquid ratio 1:9, ultrasonic extraction time 40 min. The result indicates that the content of the tea saponin could be effectively improved through the ultrasonic technology.

Abstract: Surface response optimization of Adsorption Conditions of Cr(VI) wastewater by modified brewer's grains with the factors of pH value, adsorption temperature, adsorption time, amount of adsorbent and the response of adsorption rate were studied. The optimal parameters for Adsorption Conditions were of adsorbent concentration of 60 mg·L-1, adsorbent particle size of 60~80 mesh, pH 2.23, adsorbent amount of 3.64 g·L-1, adsorption time and temperature of 1.13 h and 30 °C, respectively. The maximal absorption rate got 97.45%.The modified brewer's grains is a promising, cheap, efficient, new biological materials of adsorption for Cr (VI) in wastewater.

Abstract: The test treat printing and dyeing wastewater by the new MBR. In the process of operation, the membrane water flux reduced with time increasing. In the physical cleaning methods, aeration and water backwashing could recover the membrane flux to 62% and 70% respectively. In the test, chemical cleaning effect was better. The membrane was soaked in the solution combined with sodium hypochlorite solution, H₂SO₄ solution and citric acid solution. The membrane flux could recover to more than 90% by this method.

Abstract: Waste activated carbon (AC) containing caffeine was produced during the process of the production for caffeine. The process of treatment caffeine-saturated AC using thermal regeneration was explored and factors on the regeneration of activated carbon were investigated. The optimum conditions obtained were: temperature is 650 °C, the regeneration time is 180 min, the carrier gas velocity is 0.002 m/s, carbon layer thickness is 0.1 m. Under these conditions, activated carbon regeneration efficiency reached 90.3%. In addition, the pore structure of activated carbon before and after regeneration was characterized and the activated carbon surface area and pore size distribution under optimum conditions were determined by the adsorption isotherms.

Abstract: This paper presented Low investment and low running cost Two-phase Anaerobic Baffle Treatment Craft for living wastewater treatment, it designed Two-phase anaerobic reactor and carried out a successful launch and Experiment research. The results are as follows: 1. The experiment uses the start method that by shortening HRT to raise the load, after 53 days completes experiment start.2. By the analysis of HRT to the system effect, suggest that the best HRT is 6 h when the craft processes sewage. 3. The system clean rates of the total nitrogen and total phosphoric are respectively 21.05% and 20.1%.4. The temperature has an influence on clean effect of the system, when the temperature descends from 20 °C to 10 °C, system clean rate of average COD descends from 87.1% to 52.4%. 5. Reactor VFA and PH measurement results express that the craft could circulate stably and efficiently.

Abstract: Source water polluted by algae, ammonium and organic matter has been studied for many years. Sudden pollution incidents of source water have been reported across the whole country. Seasonal variability of rainfall across China has resulted in floods or droughts, thus incurred the high concentration of algae, ammonium and organic matter, causing severe challenges to the conventional water purification facilities. However, the conventional water treatment process is often unavailable to keep the safety of source water for drinking when sudden pollution occurs. Meanwhile, byproducts are often to be found over the whole treatment process, it is high time that researchers took effective measures to deal with this problem. In the present work, an overview of the recent research dealing with source water suddenly polluted by algae, ammonium and organic matter is presented.

Abstract: Leachate biochemical effluent containing large quantities of refractory matters are difficult to degrade by traditional biological processes. Photocatalysis technology seems to be a promising solution for leachate biochemical effluent because it can oxidize refractory organic compounds to harmless inorganics. But there are two key problems in TiO₂ photocatalytic degradation of biologically treated leachate. One is low quantum yield, the other is low photocatalytic activity in the visible-light region. The advice about solar photocatalytic degradation of biologically treated leachate using transition metal-nonmetal co-doped TiO₂ is put forward.

Abstract: By using natural bamboo as biotemplate, we synthesized mesoporous silica by Hydrothermal method followed by calcination at 650°C. And it was functionalized with aminopropyltriethoxysilane (APTS) in dry toluene under nitrogen atmosphere. As-synthesized Amino-functionalized mesoporous silica (NH₂-MS) were characterized by scanning electron microscope (SEM), nitrogen adsorption/desorption (BET), Fourier transform infrared spectra (FT-IR).The results indicated that the obtained particles retained the morphology of bamboo and possessed mesoporous structrure. Adsorption measurement results indicates the Pb (II) adsorption isotherm fits Freundlich model and maximum adsorption capacity of 143.4mg/g, the pseudo second-order kinetic model provided the best fit to the experimental data.

Abstract: Because of the shortage crisis of phosphorus element and environmental problems caused by excess discharge of phosphorus compounds into nature water bodies, phosphorus recovery had been research hotspot. Poly-phosphate (poly-P) released from sewage sludge after thermal treatment could be recovered successfully as magnesium ammonium phosphate hexahydrate (MgNH₄PO₄·6H₂O) commonly known as struvite in present study. This phenomenon was the first time to be found in phosphorus recovery from sewage sludge. The parameters affected struvite formation with poly-P had been tested. Poly-P indicated better characteristics in phosphorus recovery compared with ortho-phosphate (Pi) because it can be precipitated at lower pH condition even neutral condition, with less addition of magnesium element.

Abstract: Wood vinegar, as one of the main products of pyrolysis of wood, is very useful, but its system is not stable, easy to produce surface floating oil and precipitation. By test, it was found that 200 mg cetyl trimethyl ammonium bromide (CTMAB) was added to a liter of wood vinegar, and was stirred for 2 hours, wood vinegar surface floating oil and precipitation could be greatly reduced . It would provide useful data for the subsequent development of the wood vinegar.