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1.
以硝酸锌、硫化钠和活性炭为原料,采用化学沉淀法制备活性炭(AC)负载纳米硫化锌的复合材料Zn S/AC。利用SEM、EDS、XRD、FTIR、BET等对其进行了表征。考察了Zn S/AC对水溶液中铀酰离子(UO_2~(2+))的吸附性能,探讨了吸附时间、初始铀酰离子质量浓度、pH、吸附剂投加量、温度等对吸附性能的影响,并对吸附过程进行了热力学和动力学模拟,探讨了吸附机理。结果表明,Zn S/AC的比表面积为201.1961m~2/g,明显大于活性炭的比表面积(165.0240 m~2/g),平均孔径为4.70 nm,孔容为0.038 cm~3/g。在初始铀酰离子质量浓度为35 mg/L、pH=6、吸附时间为120 min、Zn S/AC投加量为0.01 g、处理温度为50℃下,吸附剂对铀酰离子的吸附量为63.75 mg/g。吸附过程符合准二级动力学方程和Langmuir吸附等温模型,热力学参数?G<0、?S>0、?H>0,表明该吸附是一个自发的吸热过程。  相似文献   

2.
《应用化工》2022,(2):219-223
以亲铀真菌黑曲霉和纳米Fe_3O_4为原料,制备了一种新型黑曲霉磁性生物吸附剂(Nano-Fe_3O_4 modified Aspergillus niger,NFAN)。研究了初始p H值、吸附时间、吸附剂投加量以及铀初始浓度等对NFAN吸附铀酰离子的影响,分析了吸附铀过程的动力学及热力学规律。结果表明,NFAN在初始浓度为6 mg/L,p H=7,NFAN的用量为0.15 g/L,吸附4 h。在此条件下,NFAN的铀吸附量为60.05 mg/g,铀吸附率可达76.36%,吸附过程符合准二级动力学模型。  相似文献   

3.
以亲铀真菌黑曲霉和纳米Fe_3O_4为原料,制备了一种新型黑曲霉磁性生物吸附剂(Nano-Fe_3O_4 modified Aspergillus niger,NFAN)。研究了初始p H值、吸附时间、吸附剂投加量以及铀初始浓度等对NFAN吸附铀酰离子的影响,分析了吸附铀过程的动力学及热力学规律。结果表明,NFAN在初始浓度为6 mg/L,p H=7,NFAN的用量为0.15 g/L,吸附4 h。在此条件下,NFAN的铀吸附量为60.05 mg/g,铀吸附率可达76.36%,吸附过程符合准二级动力学模型。  相似文献   

4.
活性炭吸附处理化学镀镍废液的研究   总被引:1,自引:0,他引:1  
研究了粉状活性炭对水溶液中低质量浓度柠檬酸络合镍离子的吸附行为,在静态吸附条件下,考察了柠檬酸络合剂质量浓度、吸附剂投加量、pH、温度等因素对粉状活性炭吸附镍离子的影响.试验结果表明,溶液pH和粉状活性炭投加量是影响镍离子吸附的重要因素.溶液初始pH为11.0,ρ(活性炭)为10.0g/L时,镍离子的去除率达到72.3...  相似文献   

5.
《应用化工》2022,(12):2838-2842
以橘子皮、碱性氧化橘子皮的吸附废水中Pb(2+),研究吸附剂投加量、pH、吸附时间等对Pb(2+),研究吸附剂投加量、pH、吸附时间等对Pb(2+)去除率的影响吸附。结果表明,在初始离子浓度50 mg/L,投加量为1.0 g/L,pH 5.5,温度30℃,吸附时间2 h时,碱性氧化改性的橘子皮比普通橘子皮对Pb(2+)去除率的影响吸附。结果表明,在初始离子浓度50 mg/L,投加量为1.0 g/L,pH 5.5,温度30℃,吸附时间2 h时,碱性氧化改性的橘子皮比普通橘子皮对Pb(2+)的吸附效果更佳,去除率达到98.52%。准二级动力学方程和Langmuir吸附等温模型更加符合吸附过程。吸附过程是单分子层吸附,以化学吸附为主。  相似文献   

6.
以污泥热解半焦为吸附剂,研究其对模拟罗丹明B(RhB)染料废水的吸附行为。考察了吸附剂投加量、RhB溶液初始浓度、温度、pH对半焦吸附RhB结果的影响。结果表明,半焦投加量、温度及pH的升高均可提高RhB的去除率,SiO_2的骨架作用、较大的比表面积及良好的孔隙结构为吸附RhB提供了更多的吸附点位。随着RhB初始浓度的增加,更高的浓度差推动RhB分子由吸附剂表面向其内部迁移,提高了RhB的吸附量。准二级动力学模型和颗粒内扩散模型能较准确地描述吸附动力学过程。吸附平衡研究表明,Langmuir模型比Freundlich模型能更好地拟合吸附过程,最大饱和吸附量为46.51 mg/g。热力学计算结果显示,污泥热解半焦吸附水中RhB为自发的吸热过程。  相似文献   

7.
热改性废茶叶吸附刚果红性能的研究   总被引:1,自引:0,他引:1  
采用热改性废茶叶吸附刚果红染料,考察了pH、吸附剂投加量、染料液浓度和温度对热改性废茶叶吸附染料性能的影响。采用SEM和BET研究了热改性茶叶的基本物理化学特性,最后采用伪一阶动力学模型和伪二阶动力学模型拟合了改性废茶叶对刚果红染料的吸附动力学过程,并对其吸附热力学进行分析。结果表明,热改性废茶叶表面出现了形状各异的小孔,其比表面积、总孔容和平均孔径比改性前增加较多;当溶液质量浓度为50 mg/L、pH为4、吸附剂投加量为0.4 g/L、温度为35℃时,染料的吸附率达到最佳,为98.4%,吸附量为123 mg/g;热改性废茶叶对刚果红吸附动力学符合伪二阶动力学模型,吸附过程是由物理吸附和化学吸附共同决定的。热力学分析表明,吸附过程是自发进行的吸热过程。  相似文献   

8.
以污泥热解半焦为吸附剂,研究其对模拟罗丹明B(RhB)染料废水的吸附行为。考察了吸附剂投加量、RhB溶液初始浓度、温度、pH对半焦吸附RhB结果的影响。结果表明,半焦投加量、温度及pH的升高均可提高RhB的去除率,SiO_2的骨架作用、较大的比表面积及良好的孔隙结构为吸附RhB提供了更多的吸附点位。随着RhB初始浓度的增加,更高的浓度差推动RhB分子由吸附剂表面向其内部迁移,提高了RhB的吸附量。准二级动力学模型和颗粒内扩散模型能较准确地描述吸附动力学过程。吸附平衡研究表明,Langmuir模型比Freundlich模型能更好地拟合吸附过程,最大饱和吸附量为46.51 mg/g。热力学计算结果显示,污泥热解半焦吸附水中RhB为自发的吸热过程。  相似文献   

9.
利用十六烷基三甲基溴化铵(CTAB)对颗粒活性炭进行改性。用红外光谱(FT-IR)、X射线衍射(XRD)、场发射扫描电子显微镜(FESEM)和氮吸附脱附法对改性活性炭的结构和组成进行表征。用单一变量法研究了CTAB的质量浓度和初始pH值对CTAB活性炭改性的影响,研究了吸附时间、吸附温度、苯酚初始质量浓度、苯酚pH、CTAB改性活性炭投加量等对苯酚去除率的影响,并对吸附过程进行了动力学研究。得到了最佳吸附条件为:以质量浓度为2g/L的CTAB改性活性炭为吸附剂,CTAB改性活性炭投加量为7g/L、吸附温度为35℃、吸附时间为90min、苯酚初始质量浓度为200mg/L、初始pH=6时,苯酚去除率达到94.76%,CTAB改性活性炭的吸附量为27.07mg/g。Langmuir等温吸附模型可较好地描述CTAB改性活性炭对水中苯酚的等温吸附过程,通过Langmuir模型计算得到吸附剂对苯酚的最大单位吸附量为72.62mg/g。CTAB改性活性炭对苯酚的吸附过程符合拟二级动力学方程。  相似文献   

10.
采用硝酸-高锰酸钾活化法对制备的柚子皮生物炭进行改性处理,并将其作为吸附剂探究了其对亚甲基蓝的吸附性能。通过静态吸附实验考察了亚甲基蓝溶液的pH、初始浓度、吸附时间、吸附温度、吸附剂投加量等条件对吸附效果的影响,并确定了该吸附过程的吸附动力学、吸附等温线和吸附热力学。实验结果表明,在改性生物炭投加量为0.6 g/L、pH 7、亚甲基蓝溶液浓度为100 mg/L、50℃吸附180 min的条件下,改性生物炭对亚甲基蓝的吸附容量为68.28 mg/g。通过准二级动力学方程和Freundlich方程更好的描述了该吸附过程,同时吸附热力学表明该吸附过程是一个自发吸热过程。  相似文献   

11.
陈建文 《广东化工》2006,33(6):79-81
乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。  相似文献   

12.
阐述并比较了几种加压设备在乙炔加压清净过程中的性能和特点。  相似文献   

13.
本文通过三个厂家提供的三种煤样燃烧热的测定,由测定结果综合得出3号煤样燃烧最完全、燃烧热也最大,是三个煤样中最好的一种。  相似文献   

14.
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3. __________ Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008.  相似文献   

15.
水泥水化热是中、低热水泥和核电工程用水泥的一项关键的技术指标。全球范围内测定水泥水化热的方法有溶解法、直接法/半绝热法、等温传导量热法三种。本文总结了中、美、欧相关方法标准,对其测试原理、仪器设备、试验过程等方面进行了比对,并对其在领域的应用做了简单的概括。  相似文献   

16.
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out.  相似文献   

17.
我国聚碳酸酯工业发展概况   总被引:5,自引:2,他引:3  
房梅华  夏冶 《塑料工业》1999,27(3):46-47
介绍我国聚碳酸酯生产能力和消费需求,对聚碳酸酯在信息工业中的应用作了简短介绍  相似文献   

18.
论述了涂装工艺设计对涂装设备投资、涂装生产成本的影响。  相似文献   

19.
The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003  相似文献   

20.
A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%.  相似文献   

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