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1.
通过对直接进样离子色谱测定高氯酸盐的分析条件进行优化,最终采用IonPac AS20(250mm×4mm)色谱柱,40mmol/LKOH淋洗液,1.20mL/min流速,1mL进样体积,对成都市面上几种鞭炮中高氯酸盐含量进行了分析测定。方法线性范围宽,精密度好,用于鞭炮中高氯酸盐的测定,回收率在91.0%~114%之间,结果满意。  相似文献   

2.
通过实验研究建立了自动固相萃取-高效液相色谱测定炼化废水中16种多环芳烃(PAHs)的方法。研究结果表明,利用Agilent Eclipse XDB-C18色谱分离柱,以乙腈和水为流动相,采用梯度淋洗和变化波长的紫外、荧光程序可测定炼化废水中痕量的16种PAHs。最优固相萃取条件为:15mL甲醇改进剂、10mL萃取柱活化溶剂、5mL/min的萃取流速、分3次共计15mL洗脱溶剂、0.5mL/min洗脱速率。在此优化条件下,方法检出限低于HJ 478—2009《水质多环芳烃的测定液液萃取和固相萃取高效液相色谱法》,精密度相对标准偏差(RSD)小于10%,标准曲线线性系数r≥0.999。  相似文献   

3.
铵与碱性酚和次氯酸钠反应生成靛蓝化合物,其色度与铵的浓度成正比,亚硝基氰化物使蓝色增强,在660nm处测量吸光度值;采用Flow Solution-IV^+(FS-IV^+)流动注射仪测定地表水中氨氮,检测范围0~10.00mg/L,检出限0.008mg/L,分析速率51个样S/h;对方法精密度、准确度、加标回收进行了实验,结果令人满意。该方法具有自动进样、分析速率快、试剂耗量低等优点,可应用于大批量常规地表水分析。  相似文献   

4.
本文建立了活性炭管吸附CS2解析气相色谱法测定车间空气中微量O,O-二乙基硫代磷酰氯含量的方法,柱温1400c、汽化室温度为250℃、检测器温度250℃,氮气流量为50mL/min,用150mg活性炭管,采样流速为100-200mL/min时,其吸收效率为100%,解析效率为92.5%。方法的相对标准偏差小于10%(n=5),方法检出限为0.3mg/m^3。  相似文献   

5.
通过测定不同采收期和不同部位川楝子中川楝素的含量,为确定川楝子最佳采收期提供依据。采用高效液相色谱法,色谱柱Agilent Zorbax SB-C18(4.6mm×150mm,5μm),流动相乙腈—水(28∶72),流速1.0mL/min,检测波长210nm,柱温35℃。不同采收期川楝子中川楝素以1—2月间采收的含量最高;同一采收期的川楝子果核和果肉中川楝素含量最高,外果皮次之,种子中未检出川楝素。  相似文献   

6.
高效液相法测定牡丹皮药材中丹皮酚的含量   总被引:1,自引:0,他引:1  
用高效液相色谱法测定5个产地丹皮药材的丹皮酚含量。色谱柱为菲罗门LunaC18柱(5μm,4.6mm×250mm),流动相为甲醇—水(45∶55),流速1mL/min,检测波长274nm,柱温25℃。结果表明,丹皮酚在0.432—4.32μg线性良好,相关系数r=0.9997,平均回收率为100.08%,RSD为2.85%(n=5)。丹皮酚含量按其平均值为安徽丹皮>陕西丹皮>山东丹皮>河南丹皮>重庆丹皮。该方法快速简便,结果准确可靠。  相似文献   

7.
针对含油污泥危害性大、难处理的环保难题,以实现含油污泥资源化利用为目标,开展了含油污泥热解实验研究,优化了热解工艺,并对热解产物进行了分析。在催化剂加量1.2%、热解温度为420℃、停留时间3.0 h、加热速率12℃/min、N2流速为90 mL/min条件下对含油污泥进行热解,结果表明:热解油回收率 可达72.35%;热解回收油品质有较大的改善,产生的不凝气体组分可用于燃烧供热,热解残渣热值较高,可制成燃料重复利用,实现了含油污泥的资源化利用。  相似文献   

8.
随着社会工业化进程的不断加快与发展,化工废水量也大幅增加,对环境的危害日益加剧。利用微波液相放电产生等离子体氧化处理难降解有机废水是一种有效的新技术。文章阐述了微波液相放电产生等离子体氧化技术的反应机理及技术优势,通过实验验证了该技术处理难生物降解有机废水的影响因素,并针对 这项技术应用中需要深化探索的关键点给出建议。实验结果表明:输入功率1000W,水体流速250mL/min,pH值6.0,H2O2加量为0.8%的条件下, 微波液相放电氧化反应能在20min内,对有机废水(COD原值5000mg/L)的COD去除率达98%;在最佳条件下反应10min后,B/C值从0.12提高到0.31以上,废水性质由难生物降 解转变为可生物降解,处理成本为41.00元/m3。  相似文献   

9.
按国际标准方法 ISO 14403:2002与《海洋监测规范》GB 17378.4-2007的原理,对海水氰化物的实际样品与加标样品分别使用连续流动分析法和分光光度法同时进行测定。结果显示,两种方法对海水氰化物的测定没有显著差异,但采用连续流动分析法的加标回收率在92.9%~95.6%之间,优于分光光度法(85.9%~91.9%),由此说明连续流动分析法对海水氰化物测定的准确度和精密度优于分光光度法,可以代替常规方法用于海水氰化物的测定。  相似文献   

10.
本文建立了超高效液相色谱-串联四极杆质谱分析环境水样中对苯二胺的分析方法。方法使用C18反相柱为分离柱,柱温30℃,流速0.3ml/min,80%甲醇+20%纯水作流动相,保留时间1.92min,使用具ESI(+)源的质谱作检测器。在此条件下,水样过0.45μm滤膜后可直接进样,进样体积10μl,检出限可达0.028μg/L,在0.10~4.00μg/L范围内线性良好(R=0.9998);相对标准偏差在0.7%~4.9%之间,样品加标回收率在88.2%~118%之间,应用到实际环境水样分析中也具有令人满意的结果。该方法灵敏度高,快速简单,适用于环境水样中对苯二胺的分析。  相似文献   

11.
In the present work, characteristics of ethanol production from a single particle composing of pretreated rice straw, cellulase, and β-glucosidase were invesitgated by simultaneous saccharification and fermentation (SSF). The experiment experienced a start-up stage for S. cerevisiae biofilm formation, which was operated at an initial pH value of 4.8 for yeast solution, culture temperature of 30°C, flow rate of 0.8 mL/min for yeast solution, and stably operating stage for ethanol production at a culture temperature of 30°C. Investigations found that the maximal ethanol yield of 9.7 mg/g and the biofilm thickness of 0.37 mm were obtained at 30 mL/min of carrier gas flow rate. Also, the optimal interval time of water supplement was 4 h for SSF. The results show that the appropriate gas flow rate and the interval time of water supplement can keep the high activities of biofilm and enzymes during SSF and result in a high ethanol yield.  相似文献   

12.
The fast growth of the palm oil industry in Malaysia is associated with various waste products, namely the empty fruit bunches (EFB), which have a negative impact on the environment. Therefore, these wastes were utilized as a cheap raw material for the production of activated carbon (AC) with less energy consumption. One-step steam pyrolysis was used to produce AC from oil palm empty fruit bunch fibers (EFBF) by varying the operating parameters of temperature, steam flow rate, and activation time using two-level full factorial experimental design (FFD). Ten samples of AC were prepared and the optimized production conditions were chosen based on the ability to adsorb and remove cadmium. Physical activation comprised of carbonization for 30 min using nitrogen gas (N2), followed by activation with steam at different flow rates (2.0, 3.0, and 4.0 ml/min), temperatures (600, 750, and 900°C) and times (15, 30, and 45 min). The AC sample produced at an activation temperature of 900°C with a steam flow rate of 2.0 ml/min and activation time of 15 min was selected as the best adsorbent with a total yield of 21.7%. It had adsorbed more than 97% of total cadmium from aqueous solution within 2 min of the contact time. Characterization of EFBF-based AC by SEM and BET surface area analysis had shown a good-quality adsorbent with highly active sites and well-developed pores with BET surface area of 635.16 m2/g. Experimental results indicated that the prepared AC from EFBF provide a promising solution in water and wastewater treatment.  相似文献   

13.
采用TG研究溶剂型聚氨酯涂料废物在不同升温速率、N2气氛影响下的热解特性规律。升温速率取5,10,20,30℃/min;气氛取N2气氛(50 m L/min);实验温度范围为20~800℃。研究表明,随着升温速率的增大,涂料废物热解反应各阶段起始温度、终止温度、最大失重速率温度均向高温方向移动。在500℃时,涂料废物的热分解已基本完成。运用Kissinger法和Flynn-Wall-Ozawa法进行热解动力学分析,得到溶剂型聚氨酯涂料废物热解阶段的表观活化能为196.053 3 kJ/mol。  相似文献   

14.
Continuous flow transesterification of waste frying oil (WFO) with methanol for the biodiesel production was tested in a laboratory scale jacketed reactive distillation (RD) unit packed with clam shell based CaO as solid catalyst. The physiochemical properties of the clam shell catalysts were characterized by X-ray Diffraction (XRD), Brunauer–Emmett–Teller (BET), Scanning Electron Microscopy (SEM), and Energy Dispersive Atomic X-ray Spectrometry (EDAX). The effects of the reactant flow rate, methanol-to-oil ratio, and catalyst bed height were studied to obtain the maximum methyl ester conversion. Reboiler temperature of 65°C was maintained throughout the process for product purification and the system reached the steady state at 7 hr. The experimental results revealed that the jacketed RD system packed with clam shell based CaO showed high catalytic activity for continuous production of biodiesel and a maximum methyl ester conversion of 94.41% was obtained at a reactant flow rate of 0.2 mL/min, methanol/oil ratio of 6:1, and catalyst bed height of 180 mm.  相似文献   

15.
萃取预处理苯胺基乙腈生产废水试验研究   总被引:2,自引:0,他引:2  
在苯胺基乙腈生产过程中会产生含苯胺、苯胺基乙腈、氰化物等高浓度高毒性高氨氮有机废水,可生化性较差。本试验以甲苯为萃取剂,保持原水的pH值不变,相比为0.33,经三级逆流萃取处理后,苯胺、总氰化物、氨氮和COD的萃取率可分别达到约91%、93%、42%和52%,BOD/COD由0.23提高到0.27,提高了废水的可生化性,甲苯可采用酸洗再生加蒸馏再生联合的处理方式。  相似文献   

16.
Turkey has a drastic potential in terms of biomass energy and it would be of utmost importance for our energy mix if this huge amount of energy is to be utilized. Thermochemical conversion is the most dominant one among the energy conversion processes. The carbonization process is the key point in determining the kinetic parameters of the fuels utilized. Thereafter, the kinetic parameters obtained from carbonization would be utilized in designing the thermochemical conversion equipments. In this study, the thermal decomposition behavior of hazelnut shells was investigated via dynamical thermogravimetry (TG) under N2 atmosphere. In order to determine the effects of heating rate and gas flow rate, the experiments were performed in four different heating rates of 5, 20, 50, and 100 K/min and two different nitrogen flow rates of 50 and 100 cm3/min. As the heating rate was increased, peak temperature was increased, maximum temperature shifted to the right (higher T zones) and the maximum rate of weight loss was increased. In addition, lignin decomposition temperature interval was decreased whereas; cellulose decomposition temperature interval was increased. Increasing the heating rate from 5 to 20 K/min, hemicellulose decomposition temperature interval was increased. Total weight loss was slightly increased by the increase of gas flow rate. Kinetic parameters were calculated according to Coats Redfern method. It was found that activation energies of thermal decomposition reactions of hazelnut shell varied between 1.30 and 32.19 kJ/mol.  相似文献   

17.
Continuous fixed-bed studies were undertaken to evaluate the efficiency of jackfruit leaf powder (JLP) as an adsorbent for the removal of methylene blue (MB) from aqueous solution under the effect of various process parameters like bed depth (5–10 cm), flow rate (30–50 mL/min) and initial MB concentrations (100–300 mg/L). The pH at point of zero charge (pHPZC) of the adsorbent was determined by the titration method and a value of 3.9 was obtained. A FTIR of the adsorbent was done before and after the adsorption to find the potential adsorption sites for interaction with methylene blue molecules. The results showed that the total adsorbed quantities and equilibrium uptake decreased with increasing flow rate and increased with increasing initial MB concentration. The longest breakthrough time and maximum MB adsorption were obtained at pH 10. The results showed that the column performed well at low flow rate. Also, breakthrough time and exhaustion time increased with increasing bed depth. The bed-depth service time (BDST) model and the Thomas model were applied to the adsorption of MB at different bed depths, flow rates, influent concentrations and pH to predict the breakthrough curves and to determine the characteristic parameters of the column that are useful for process design. The two model predictions were in very good agreement with the experimental results at all the process parameters studied indicating that they were very suitable for JLP column design.  相似文献   

18.
为实现2000年污染源达标排放和污染物总量控制目标,大庆油田制定了“工业污染源达标计划”、“污染物排放总量控制计划”;提出了2000年超标企业排污总量削减方案;对化工助剂总厂和腈纶工程的化工污水、三次采油工程新增化工含氰污水的治理提出了具体措施  相似文献   

19.
Because organic sorption in soil may never reach equilibrium, a thin-disc flow nonequilibrium method may be helpful in understanding herbicide-soil interactions. This research was conducted to (i) determine the influence of incubation time on imazaquin [2-(4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl)-3-quinolinecarboxylic acid] desorption from soil, (ii) examine the influence of solution flow velocities on desorption, and (iii) elucidate the most appropriate kinetic model to describe imazaquin leaching. Soil at 7.5% moisture w/w was treated with imazaquin and incubated for 24, 72, and 168 h. Treated soil was sealed in an in-line filter apparatus and rinsed with 5.0 mM CaCl2 at 0.33, 0.67, or 1.0 mL min(-1). Effluent was collected as 1.0-mL fractions for a total of 50 mL. Flow was stopped for 24 h. When flow resumed, fractions were collected for an additional 15 mL. After the initial desorption, 79% of the imazaquin incubated for 24 h was leached. Increasing incubation time beyond 24 h reduced imazaquin leaching. After both desorption events, 13% of the initially applied imazaquin remained in the soil incubated for 168 h, compared with 7% with soil incubated for 24 h. Elovich and Freundlich kinetics accounted for 98% of the variance observed in the imazaquin desorption curves. First-order and diffusion kinetics accounted for 91% of the variance. Incubating soil for 72 h before desorption reduced the rate of imazaquin desorption by approximately 12%, compared with the 24-h incubation treatment. Imazaquin desorption was not affected by wash solution flow rate. These data suggest that the kinetics of desorption in prolonged desorption events are limited by transport phenomena (i.e., particle and film diffusion).  相似文献   

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