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161.
《先进技术聚合物》2018,29(6):1632-1648
In the present research, the low water flux of polyphenylsulfone membranes was addressed, and a novel improvement in their water permeation and fouling resistance was achieved using polyethylene glycol (PEG) as the hydrophilic additive. Scanning electron microscopy and field emission scanning electron microscopy, atomic force microscopy, attenuated total reflection Fourier‐transform infrared spectroscopy, thermogravimetric analysis, and tensile test were applied for the investigation of membrane morphology, surface topography, surface chemical structure, thermal stability, and mechanical properties, respectively. Moreover, the relative hydrophilicity/hydrophobicity of the membranes was assessed via determination of membrane water uptake capacity and water contact angle. The membrane performance was studied and compared by determination of pure water flux and filtration of canned beans production wastewater as well as bovine serum albumin solution. The filtration results indicated a remarkable pure water flux and 100% turbidity rejection provided by the polyphenylsulfone/PEG 20 000 membrane. In addition, it was confirmed that the amount of residual PEG within the membrane was increased with increasing PEG molecular weight and concentration. 相似文献
162.
Parimal Pal 《Separation & Purification Reviews》2018,47(3):179-198
The literature on the treatment of pharmaceutical wastewater over the period 1990–2015 has been reviewed to develop a sustainable treatment strategy. Analysis of the existing methods for treatment and disposal practices of pharmaceutical waste has been undertaken on the classification of the treatment methods under well-identified broad specific groups. The review reveals the associated merits and demerits of the traditional and the emerging methods and the challenges involved in overcoming the shortcomings. Considering the very diverse nature of the contaminants and the poor success rates of the existing technologies, it transpires that no single classical technology is capable of fully taking care of the hazards emanating from pharmaceutical waste discharges. On the other hand, some recent technologies such as membrane-integrated hybrid technologies are emerging as more successful ones than the conventional technologies. But, scale up confidence with respect to such new technologies is still very limited and needs to be substantially improved through extensive investigation on the pilot scale using real pharmaceutical wastewater rather than synthetic wastewater. This review directs the research focus to the development of sustainable treatment technologies. 相似文献
163.
Luciana A. I. de Azeredo Leda R. Castilho Selma G. F. Leite Rosalie R. R. Coelho Denise M. G. Freire 《Applied biochemistry and biotechnology》2003,108(1-3):749-755
Streptomyces are important microorganisms because of their capacity to produce numerous bioactive molecules. In the present work protease
production, by Streptomyces sp. 594 isolated from a Brazilian Cerrado soil, was maximized by optimizing a low-cost culture medium composition (casitone
and sugarcane molasses) using statistical experimental design. The final protease activity (56 U/mL) was 2.8-fold and 58-fold
higher than that obtained in the beginning of this study, and in a previous work, using an actinomycete selection medium,
respectively. Protease production, not growth associated, appeared to be modulated by an inducer system, whereby the C/N ratio
seemed to play a significant role. 相似文献
164.
ZrxCe1-xO2催化剂催化湿式氧化乙酸的活性研究 总被引:1,自引:0,他引:1
采用共沉淀法制备了ZrxCe1-xO2催化剂, 利用BET, XRD和XPS对其进行了表征, 并研究了催化剂催化湿式氧化乙酸的活性. 结果表明: Zr和Ce摩尔比为1∶9的催化剂催化湿式氧化乙酸时具有最好的活性, 当乙酸溶液的初始化学需氧量(COD)为5000 mg/L, 反应温度为230 ℃, 压力为5 MPa时, 120 min后, COD的去除率为76% . 催化剂具有良好的活性是因为在CeO2中加入Zr能够增大催化剂的比表面积和表面缺陷氧的含量, 并最终加快了HO2•自由基的产生, 从而提高了催化剂的活性. 相似文献
165.
K2CO3活化煤矸石制备活性炭吸附剂 总被引:5,自引:0,他引:5
用K2CO3化学活化煤矸石制备适用于废水处理的活性炭吸附剂.考察了活化条件对产物的比表面、孔体积及灰分的影响.增加了前处理和后处理步骤以改善产物的性能.最佳条件下获得的活性炭吸附剂BET比表面达1236m2/g,孔体积0.679cm3/g.所制得的吸附剂表面是疏水性的,对水溶液中的酚类污染物有良好的吸附性能. 相似文献
166.
167.
建立了利用二硫代安替比林甲烷光度法测定铅冶炼废水中微量砷的分析方法。在1.8mol·L^-1硫酸介质中,砷与二硫代安替比林甲烷显色剂发生灵敏的显色反应,最大吸收波长为331nm。考察了显色剂用量、显色反应时间、介质、酸度、不同价态砷对测定结果的影响。结果表明:使用4cm的比色皿,As^3+的质量浓度在0.04~0.6mg·L^-1内与其对应的吸光度之间呈线性关系,线性回归方程为y=1.063 x+0.001,相关系数为0.999 3,表观摩尔吸光系数为2.7×10^4L·mol^-1·cm^-1。按照标准加入法进行回收试验,测得回收率为97.0%~105%,相对标准偏差(n=5)为1.3%~2.6%,该方法用于测定铅冶炼废水中微量砷的结果满意。 相似文献
168.
169.
Ali N. Siyal Saima Q. Memon Aydan Elçi Abdullah Akdogan Aysen Hol Aslihan A. Kartal 《International journal of environmental analytical chemistry》2013,93(14-15):1463-1477
Polystyrene (PS) was extracted from styrofoam waste and functionalised with schiff base, N,N-bis(salicylidene)cyclohexanediamine (SCHD) through an azo spacer. The resin was characterised and used for preconcentration of Pb(II), Ni(II) and Cd(II) ions prior to their trace determinations by microsample injection system–coupled flame atomic absorption spectrometry (MIS-FAAS). The recoveries of studied metal ions were achieved ≥96.0% with relative standard deviation (RSD) ≤4.5 at optimum parameters: pH 8; resin amount 300 mg; flow rates 3.0 mL min?1 of sample solution; and 2.0 mL min?1 of eluent (2.0 mol L?1 HNO3). The limits of detection (LODs) and limits of quantification (LOQs) were found to be 0.32, 0.23 and 0.21 and 1.10, 0.78 and 0.69 μg L?1, respectively, with preconcentration factors (PFs) of 500, 800 and 1000, respectively. The linear ranges of the method were 1–40, 1–25 and 1–20 μg L?1 for Pb(II), Ni(II) and Cd(II) ions, respectively. The accuracy and validation of the method were evaluated by analysis of certified reference materials (CRMs). The method was successfully applied for preconcentration of studied metal ions in wastewater and wastewater-irrigated vegetable samples. 相似文献
170.
Jos Luis Malvar Juan Luis Santos Julia Martín Irene Aparicio Esteban Alonso 《Molecules (Basel, Switzerland)》2020,25(22)
The release of pharmaceutically active compounds to the soils through the application of sewage sludge and the irrigation with wastewater, or even with surface water, is constant. The adsorption of these compounds onto the soil is one of the key factors affecting their fate in the environment and their potential environmental risks. In this work, the adsorption of carbamazepine (CBZ) and its metabolites, 3-hydroxy-carbamazepine (3OH-CBZ), carbamazepine-10,11-dihydro-10,11-epoxide (EP-CBZ), and 10,11-dihydro-10-hydroxycarbamazepine (10OH-CBZ), in three Mediterranean soils was evaluated using single-solute and four-solute experiments. The highest adsorptions were measured for 3OH-CBZ, followed by CBZ, EP-CBZ, and 10OH-CBZ, in that order. A high influence of the physicochemical characteristics of the compounds, pH, and soil characteristics in the adsorption of the studied compounds was observed and corroborated by the statistical analysis of the results. Moreover, a good fit was observed in the three isotherm models evaluated (linear, Freundlich, and Langmuir) in single-solute experiments (R2 > 0.90). However, a decrease of the measured adsorptions and a worse fit to the isotherm models were observed in the case of multiple-solute experiments. This could be mainly due to the competition established between the studied compounds for the active sites of the soils. 相似文献