天然肉桂油臭氧化制取苯甲醛

利用天然肉桂油中富含的肉桂醛，经过臭氧化反应和还原反应制得了苯甲醛。由该法制得的苯甲醛在国际上可作为天然苯甲醛使用。     

Ozonation of 2-Chlorophenol in Aqueous Solutions with a Packed Contactor

The dissolution of ozone and the decomposition of 2-chlorophenol were noticeably enhanced for experiments conducted in the fixed packed contactor than those conducted in a bubble column. The rate of ozone transfer was increased with the increasing amount of Pall rings contained in the packed contactor and the decreasing gas/liquid ratio (G/L) because the gas–liquid interface may be renewed effectively. The decomposition of 2-chlorophenol by ozonation was found to be faster for experiments conducted in alkaline solutions while the decomposition of total organic carbon only slightly enhanced. However, the decomposition of total organic carbon only slightly increased for experiments conducted in alkaline solutions.     

Ozonation of Spent Reactive Dye-Baths: Effect of HCO3?/CO32? Alkalinity

The effect of carbonate and bicarbonate alkalinity (soda ash buffer as 5,180 mg/L HCO3? alkalinity at pH 7 and as 5,100 mg/L CO32? alkalinity at pH 12) on the ozonation of reactive vinylsulphone dyestuffs in a simulated spent dye-bath has been studied at varying pHs. Adsorbable organic halogen (AOX) formation due to the high chloride content of the effluent and detoxification, which was evaluated in terms of the relative toxicity index Itox determined from the ED50 values for the marine photobacteria Vibrio fischeri, were also evaluated. Highest total organic carbon (56%), chemical oxygen demand (44%), and UV254 (77%) removals were achieved at pH 7 in the presence of HCO3? alkalinity. The fastest decolorization was observed for the case pH 2, the first order decolorization rate constant found as k620 = 0.16?min?1, closely followed by the pH 12 case with soda ash (k620 = 0.12?min?1) case. No positive correlation was evident between AOX, whose maximum value (=1.3 mg/L) appeared after 40 min ozonation at pH 7 and decreased to 0.54 mg/L after 120 min treatment, and Itox, which decreased to 0.16 at t = 50?min and increased rapidly thereafter. The Itox values were more related to color abatement kinetics. The maximum relative toxicity index of Itox = 0.83 occurred after 120 min. It was also established that the presence of alkalinity in the spent reactive dye-bath had no negative impact on the oxidation rates. In contrast, its absence seriously inhibited treatment efficiency. It is speculated that, with added soda ash, the carbonate radicals HCO3? and CO3??, which are more stable and selective than OH?, were produced and promoted the oxidation process.     

多级深度生化物化(MBP)工艺处理垃圾渗滤液

介绍了垃圾渗滤液多级深度生化物化处理(MBP)工艺的组成和特点,该工艺生化段主体为立环氧化沟、富氧曝气池和臭氧氧化池;物化段主体为活性炭过滤池、CMF和两级RO反渗透。以滨海新区汉沽垃圾处理场为例,介绍了该工艺在垃圾渗滤液处理工程中的实际应用。近期处理规模为55m3／d,出水达到《城市污水再生利用城市杂用水水质》(GB／T18920-2002)。直接运行费用为17-22元／m3。     

Scale-Up Study of Dye RB-19 Ozonation in a New Gas-Inducing Reactor

The purpose of this research was to study the scale-up behavior of dye RB-19 ozonation in a new gas-inducing reactor, which has been used in the NTUST laboratory on various ozonation studies over the past few years. In this scale-up study, three geometrically similar gas-inducing reactors with different diameters (D _t =0.17, 0.29, and 0.51m) were employed. Three common scale-up criteria (i.e., equal liquid surface motion, equal specific power consumption, and equal impeller tip velocity) were investigated in this research. Under the equal liquid surface motion criterion, the scale-up exponent value and constant K of the modified onset Froude number were determined to be 0.5 and 0.61, respectively. The equal specific power consumption criterion was studied under gas input condition and the scale-up exponent was found to be 0.65. The regression equation for the power number of the three different scale reactors was also obtained. The scale-up exponent of equal impeller tip velocity was determined by theory to be 1.0. The scale-up investigation of dye RB-19 ozonation was then carried out in reactors with three different diameters under the same operating conditions (e.g., initial dye concentration, initial dye/ozone molar ratio, superficial gas velocity, temperature and pH value). From the experimental results, the best-fit scale-up exponent was found to be 1.18, resulting in same dye removal rate in reactors with different diameters. The enhancement factors and chemical ozone mass transfer coefficients were also obtained for these sets of ozonation experiments.     

Electrochemical Wastewater Disinfection: Identification of Its Principal Germicidal Actions

Laboratory experiments were carried out to investigate the mechanisms of electrochemical (EC) wastewater disinfection. Artificial wastewater contaminated by Escherichia coli (E. coli) culture, and which contained different salts of NaCl, Na2SO4, and NaNO3, was used as the test medium. The experimental results do not favor the hypotheses that the EC bactericidal action was due to cell destruction by the electric field and the production of persulfate. In comparison to direct chlorination, the EC process displayed a much stronger disinfecting capability than that of electrochlorination assumed for EC disinfection. Observations with scanning electron microscopy on the E. coli bacteria of wastewater treated by different means of disinfection suggested that the cells were likely killed during the EC treatment by chemical products with oxidizing and germicidal powers similar to that of ozone and much stronger than that of chlorine. All of the findings support the theory that the major killing function of EC disinfection is provided by short-lived and high-energy intermediate EC products, such as free radicals.     

Filter Sand-Phosphate Buffer Effect on 2,4-Dinitrotoluene Ozonation

The objective of this study is to evaluate the effects of different sands and phosphate buffer on ozone decomposition by measuring the observed ozone decomposition rate constant of three different natural sands at pH 7 with and without the presence of phosphate buffer and with and without sand (i.e., aqueous ozone only). In addition, this study evaluated phosphate buffer effect on the heterogeneous catalysis of ozone for the destruction of 2,4-dinitrotoluene (DNT) by measuring the observed DNT degradation rate constant (kDNT). Ozone decomposition rates in the presence of NaOH buffer and sand were up to 7.9 times greater and 3.4 times in the presence of phosphate. In the absence of phosphate, sand reduced the observed rate of DNT degradation. In the presence of phosphate, sands enhance the observed DNT degradation rate by a factor approximately proportional to their surface manganese concentration. A proposed mechanism was developed explaining the observed effects of the phosphate in a sand ozone system.     

Joint Treatment of Wastewater from Table Olive Processing and Urban Wastewater. Integrated Ozonation – Aerobic Oxidation

Integrated ozonation‐aerobic biodegradation of table olive wastewater (diluted 1:25 with synthetic urban wastewater) is presented as a suitable technology to purify this kind of effluent. Use of ozone is recommended as a pre‐treatment step since it shows a high reactivity toward phenolic compounds (found in this type of wastewater) reducing, at the same time, the alkalinity of the media for further biological processing. An ozone dose of 45 mg L^–1 (flow rate 20 L h^–1) for a period of 35 min has been found to achieve the following goals: decrease pH, decrease phenolic content, and increase of biodegradability. The aerobic oxidation process followed first order kinetics as measured by COD depletion profiles versus time. The Arrhenius expression k = 183exp(–2214/T) was obtained for experiments of ozonated wastewater biodegradation completed at different temperatures and neutral pH.     

UHMWPE的臭氧化降解及摩擦磨损性能研究

研究了臭氧化反应对超高摩尔质量聚乙烯（UHMWPE）熔体流动性、摩擦磨损性能以及结晶性能的影响。经臭氧化反应，UHMWPE发生降解，粘均摩尔质量从2650kg／mol降低到566kg／mol，熔体质量流动速率从0增加到0．28g／10min。随臭氧化处理时间的增加，材料摩擦系数和磨损量基本不变，UHMWPE优异的磨擦磨损性能得以保持。DSC分析结果表明，随臭氧化反应时间的增加，UHMWPE熔融焓增加，结晶度增加。     

Mass Transfer of Ozone in a Novel In Situ Ozone Generator and Reactor

A porous tubular reactor that also served as an electrode for ozone generation was studied in this research to determine the effects of in situ ozone generation on mass transfer and reaction rates. Experimental data over a range of gas flow rates and ozone generation rates gave KLa values in the range 0.77–1.14?min?1. These values are more than double the values typically reported for bubble columns, and about 30% higher than that for packed beds. The specific power requirement for the laboratory-scale in situ reactor is an order of magnitude lower than that for bubble columns and stirred tank reactors that are used for ozone dissolution. A compartments-in-series fluid flow model was developed to describe the reactor system, and this model provides a good comparison to the experimental data for dissolved ozone and off-gas concentrations in the reactor. Sensitivity analyses indicate that the dissolved and off-gas ozone profiles are most sensitive to the gas–liquid partition coefficient and the overall mass transfer coefficient.