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1.
Geochemical modeling of leaching from MSWI air-pollution-control residues   总被引:1,自引:0,他引:1  
This paper provides an improved understanding of the leaching behavior of waste incineration air-pollution-control (APC) residues in a long-term perspective. Leaching was investigated by a series of batch experiments reflecting leaching conditions after initial washout of highly soluble salts from residues. Leaching experiments were performed at a range of pH-values using carbonated and noncarbonated versions of two APC residues. The leaching data were evaluated by geochemical speciation modeling and discussed with respect to possible solubility control. The leaching of major elements as well as trace elements was generally found to be strongly dependent on pH. As leaching characterization was performed in the absence of high salt levels, the presented results represent long-term leaching after initial washout from a disposal site, that is, liquid-to-solid ratios above 1-2 L/kg. The leaching of Al, Ba, Ca, Cr, Pb, S, Si, V, and Zn was found influenced by solubility control from A12O3, Al(OH)3, Ba(S,Cr)04 solid solutions, BaSO4, Ca6Al2(SO4)3(OH)12 x 26H2O, CaAl2Si4O12 x 2H2O, Ca(OH)2, CaSiO3, CaSO4 x 2H2O, CaZn2(OH)6 x 2H2O, KAlSi2O6, PbCO3, PbCrO4, Pb2O3, Pb2V2O7, Pb3(VO4)2, ZnO, Zn2SiO4, and ZnSiO3. The presented dataset and modeling results form a thorough contribution to the assessment of long-term leaching behavior of APC residues under a wide range of conditions.  相似文献   

2.
《Food chemistry》2005,92(2):305-309
Avocado honey samples were analyzed by inductively coupled plasma optical emission spectrometric. First, the botanical origin of the honeys was confirmed by melissopalynological analysis. Twenty-four minerals were quantified for each honey sample. The elements Al, Ba, Ca, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, S, Se, Si and Zn were detected in all samples; seven elements were very abundant (Ca, K, Mg, Na, P, S and Si), six were not abundant (Al, Cu, Fe, Li and Zn) and 11 were trace elements (As, Ba, Cd, Co, Cr, Mo, Ni, Mo, Pb, Se, Sr and V).  相似文献   

3.
Coal utilization byproducts (CUB), such as fly ash, contain cations that may be released during exposure to fluids such as acid rain or acid mine drainage. Researchers at the Department of Energy's National Energy Technology Laboratory (DOE/NETL) have conducted a long-term column leaching study of 32 Class F fly ash samples from pulverized coal (PC) combustion, and quantified the release of 19 cations in four leachants with a pH between 1.2 and 12. The relative solubility (M(L/T)) of each cation was defined as the total mass leached (M(L)) relative to the concentration (M(T)) of that element in the fly ash sample. A frequency distribution of relative solubility values was computed with ranges defined as insoluble, slightly soluble, moderately soluble, and very soluble. On the basis of this sample set, Ba, Cd, Fe, Pb, Sb, and Se in PC fly ash are insoluble. The elements Al, Be, Ca, Co, Cr, Cu, K, Mg, Mn, Na, Ni, and Zn are slightly to moderately acid soluble. Only Ca and Na are water soluble; As and Ca are soluble in the basic solution, The results of this study indicate that the extent to which cations in Class F PC fly ash can be leached by naturally occurring fluids is very limited.  相似文献   

4.
Surface chemistry and dissolution kinetics of divalent metal carbonates   总被引:2,自引:0,他引:2  
A surface complexation model (SCM) for divalent metal carbonates (Ca, Mg, Sr, Ba, Mn, Fe, Co, Ni, Zn, Cd, and Pb) is developed based on new electrophoretic measurements and correlation between aqueous and surface reactions stability constants. This SCM postulates the formation of the following surface species: >CO3H0, >CO3-, >CO3Me+, >MeOH0, >MeO-, >MeOH2+, >MeHCO30, and MeCO3- within the framework of a constant capacitance of the electric double layer. It can be used to describe the surface-controlled dissolution kinetics of divalent metal carbonates and allows determination of the order of dissolution reactions with respect to rate-controlling protonated carbonate surface groups in acid solutions (>CO3H0) and hydrated metal groups (>MeOH2+) in neutral to alkaline solutions. The reaction order with respect to protonated carbonate groups increases from 2 for MnCO3 and ZnCO3 to 4 for NiCO3, whereas for hydrated surface metals, it augments from 2 for ZnCO3 to approximately 4 for MnCO3 and NiCO3. The dissolution rates at 5 < or = pH < or = 8 increase in the order Ni < Mg < Co < Fe < Mn < Zn < Cd < Sr < or = Ca approximately = Ba approximately = Pb and correlate nicely with water exchange rates from the aqueous solution into the hydration sphere of the corresponding dissolved cations. Such a correlation allows the generation for all carbonates of a model describing their dissolution/precipitation kinetics, including the effect of various ligands, provided that rate constants and their activation volumes for water exchange around Me(II)-ligand dissolved complexes are available.  相似文献   

5.
利用微波消解结合电感耦合等离子体质谱检测的方法测定泸州老窖浓香型白酒蒸馏过程中,蒸馏前后的酒糟、底锅水及所得的酒样样品中Na、K、As、Pb、Cd、Sn、Ti、Mg、Fe、Cu、Mn、Zn、Ca、Al、Ni、Cr和Ba 17 种金属元素的含量,并借助SPSS统计学软件采用t检验分析酒体中对应元素的来源。结果表明,蒸馏之后超过94%的金属元素仍保留在糟醅中,不到6%的金属元素转移至白酒及底锅水中。Pb、Mn、Cr等重金属元素的转移率显著低于Na、K、Ca和Mg等矿质元素,有效减少了酒中Pb、Mn、Cr等重金属的超标几率。酒样中的Ca、Cu、K、Mg、Na、Zn和Ba等元素主要来源于糟醅,而蒸馏使用的设备则会引入Fe、Ni、Al、Sn元素,Pb和Cr等有害重金属。  相似文献   

6.
Elemental determination was carried out on 36 grape juice samples (19 organic and 17 ordinary), with the goal of identifying significant differences between the two types of juice for classification purposes. Inductively coupled plasma-mass spectrometry was used for the determination of 24 elements, Al, As, Ba, Ca, Cd, Ce, Co, Cr, Cu, Fe, La, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, Se, Sn, Ti, V, and Zn. Ba, Ce, La, Mg, P, Pb, Rb, Sn, and Ti concentrations were found to be higher in organic versus ordinary samples, while Na and Va concentrations were higher in ordinary versus organic samples. The remaining investigated elements exhibited statistically equivalent concentration levels in both types of samples. Principal component analysis (PCA) and soft independent modeling of class analogy (SIMCA) statistical techniques of the elemental fingerprints were readily able to discriminate organic from ordinary samples and can be used as alternative methods for adulteration evaluation.  相似文献   

7.
The effect of dissolved Zn, Co, Pb, Mg, and Ca on the uptake of cadmium by biogenic aragonite was investigated. Experiments were performed in batch-reactors using metal-cadmium-bearing solutions and shell fragments with diameters in different ranges, the solid/liquid ratio being 10 grams per liter. Different initial concentrations of cadmium and metals (1.0-0.005 mM) were used. Uptake takes place via heterogeneous nucleation of metal-bearing crystallites onto the shell surfaces. Cadmium removal occurs by surface precipitation of otavite. Under the conditions used here, Co and Ca as well as Pb < or = 0.3 mM and Zn < or = 0.3 mM do not have a significant effect on the removal of cadmium. At higher concentrations, Pb and Zn outcompete Cd for the dissolving carbonate ions and thus decrease significantly the Cd removal rates. In contrast, Mg has a slight enhancing effect. Pb and Zn are removed faster than Cd, precipitating as PbCO3, Pb3(CO3)2(OH)2, and Zn5(CO3)2(OH)6. Within 24-72 h, the concentrations of lead, cadmium, and zinc decrease until approximately 0.5 microM, and the presence of aragonite buffers the solution to a pH above 8 avoiding redissolution. The study demonstrates the high effectiveness of biogenic aragonite in removing Cd and other metals from polluted waters.  相似文献   

8.
The concentrations of 23 chemical elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, Sb, Se, Sr, Th, Tl, U, Zn) were determined in 51 honey samples of different botanical origin produced in Siena County (Italy). K, Ca, Na and Mg were the most abundant elements, with mean contents of 1195, 257, 96.6 and 56.7 mg/kg, respectively. The Fe, Zn and Sr contents generally ranged from 1 to 5 mg/kg. Except for Ba, Cu, Mn and Ni, the trace element contents were below 100 μg/kg. The analytical data indicated a good level of quality of the honeys, especially with regard to the concentrations of toxic trace elements, such as As, Cd, Pb and Sb, and suggested a significant influence of the botanical origin on the element composition. Some local geological and geochemical features also seemed to affect the chemistry of the honey.  相似文献   

9.
采用硝酸-高氯酸对江西赣南8个县所产的脐橙样品进行消解,电感耦合等离子体原子发射光谱法(ICP-AES)同时测定试样中Al、As、Ba、B、Ca、Co、Cr、Cu、Fe、K、Li、Mg、Mn、Ni、P、Pb、Zn、Be、Cd、Se、Sr、La、Ce、Y、Sm、Lu等元素的含量。该法的相对标准偏差为0.42%~4.51%,加标回收率为87.7%~114.1%。实验结果表明:脐橙中含有丰富的K、Ca、P和Mg,不同县所产的脐橙各种微量元素含量存在一定差异。  相似文献   

10.
Contents of various elements in dyferent parts of the tea plant (shoot, mature leaf, small stem, thick wood and root), black tea manufactured by the crush-tear-curl and orthodox processes, and tea brew after 1 and 5 min of infusion were determined by inductively coupled plasma atomic emission spectrometry. From these, the amount of each element assimilated in the production of 1000 kg of marketable tea, as well as the quantity of each element brought into infusion and thus possib f y taken up through drinking tea, were calculated and discussed. Among the various elements assimilated by the tea plant, the shoot jraction (economically important for manufacturing commercial tea) contained high concentrations of N, P, K and Mg while the mature leaf accumulated Al, Bu, Ca, Cd, Mn, Pb and Sr. Of the dgerent elements brought into infusion while brewing black tea, the amount of K was found to be the largest (> 10000 μg g−1 tea) followed by P (700–1200 μg g−1), Mg (300–700 μg g−1), Ca and A1 (each 150–300 μg−1), Mn (60–150 μg g−1), Cu, Na, Si and Z n (each 6–50 μg g−1), B, Ba, Cr, Fe, Ni and Pb (each Id μg g−1), and Sr, Co and Gd (each <1μg g−1). The proportion of the totalamount of an element brought into infusion showed that the elements Ba, Ca, Fe and Sr were less soluble (<10 % of total amount), Al, B, Cd, Co, Cr, Cu, Mg, Mn, P, Pb, Si and Zn were moderately soluble (10–50 %), and K, Nu and Ni were highly soluble (>50%). The overall mean of the extent of solubility of all elements in 1 and 5 min showed that, out of the amount soluble in 5 min, about 68% was dissolved within 1 min.  相似文献   

11.
以云南省8 种野生牛肝菌为对象,研究子实体不同部位矿质元素含量、吸收和积累特征。采用微波消解处理样品,以电感耦合等离子体质谱法测定云南省8 种野生牛肝菌子实体菌柄、菌盖中Mg、Mn、Fe、Ni、Cu、Zn、Cr、As、Cd、Pb、Li、Ba 12 种矿质元素的含量,并用SPSS软件进行方差分析,从元素的角度对其进行安全性评价,分析牛肝菌中矿质元素的含量水平。结果显示,标准品(GBW 10015)中12 种矿质元素回收率在88%~105%之间,检出限在0.036~9.456 μg/L之间,表明该方法准确、可靠;8 种野生牛肝菌菌柄与菌盖中含有丰富的Fe、Mg、Mn、Zn和Cu元素;Zn、Mg、Cu、Cr和As元素在多数子实体内菌盖的含量高于菌柄,Li和Ba在多数牛肝菌样品中菌柄含量较高;有毒重金属元素Pb、As、Cd、Ni和Cr含量均高于GB 2762-2012《食品中污染物的限量》的规定,对人体健康有潜在风险。通过数据分析表明,野生牛肝菌中12 种矿质元素含量具有显著差异,同一元素在不同牛肝菌中的含量差异较大,相同子实体菌柄与菌盖中含量差异显著,对矿质元素和重金属元素有较好的吸收和富集能力。  相似文献   

12.
The inorganic constituents of fresh and cured jellyfish (Rhopilema esculentum), including Zn, Co, Ni, Ba, Mn, Fe, Mg, Ca, Cu, Al, Sr, Mo, Cr, Cd, Pb, Si, V, Ti, Na, K, Li, and Rb, were determined by using inductively coupled plasma optical emission spectrometry. The fresh and cured jellyfish were treated by lyophilization and microwave digestion in turn. Zn, Co, Fe, Mg, Ca, Al, Sr, Cr, Li, and K were used as the added standards to evaluate accuracy. The results show that different parts of jellyfish, such as the umbrella, oral arms, and gonads, contain different amounts of inorganic elements. The relative standard deviation values (RSD) of all elements range from 0.8% to 8.6%. For most of determined elements, RSD values are under 5%. All inorganic elements of the jellyfish can be determined simultaneously after once dissolution. The method is accurate, rapid, and convenient to determine inorganic constituents of the biological sample containing high water content.  相似文献   

13.
采用电感耦合等离子体原子发射光谱仪,对全国7 个主要产地的26 个山银花样品中的10 种金属元素的 含量进行定量分析,应用主成分分析和聚类分析对山银花资源中金属元素进行评价。结果表明:Pb、As、Fe、 Ca、Zn、Mg、Mn、Cu、Cd、Cr的平均含量分别为0.25、0.065、77.9、3 277.1、31.0、2 244.7、319.9、14.6、 0.31、0.217 mg/kg;主成分分析得出3因子模型,可解释实验数据的88.58%;主成分分析将26 个山银花样品划分 为4 类,聚类分析显示了相似的结果。研究得出山银花中金属元素的含量分布特征,为山银花资源的品质评价和 质量控制提供实验依据。  相似文献   

14.
利用元素分析建立四个产地香米的鉴别方法。利用电感耦合等离子体质谱法和电感耦合等离子体光谱法对来自泰国、越南、柬埔寨、巴基斯坦四个地区的220份香米进行包括钙、铁、钾、镁、锌、硼、铝、铬、锰、钴、镍、铜、砷、锶、硒、镉、铯、钡、铅19种元素在内的含量分析。通过判别分析建立判别模型。判别模型自校验交叉校验准确率100%,拥有极高的准确率。  相似文献   

15.
王莹  刘忠和  康万利  吴英  赵丹  张京京 《食品科学》2009,30(22):328-330
采用高压密封硝化罐消解样品,应用ICP-AES 法测定百香果果汁、果皮、种仁中20 种矿物元素 (Na、K 、C a 、Mg、Z n 、F e 、S r 、Cu 、Co 、Mn、Ge 、S e 、S n 、B a 、A l 、P b 、Hg、As 、C r 、Cd) 的含量,设计正交试验方案,通过方差分析选择最佳的试验操作条件,其回收率在95.0%~104.0% 之间,相对标准偏差小于2.15%。实验结果表明:百香果果汁、果皮、种仁中均含有丰富的Na、K、Ca、Mg、Zn、Fe、Ge等对人体有益的矿物元素,而对人体有害的元素均未检出,营养价值高,极具开发价值。  相似文献   

16.
Several polish herbal medicaments were studied to determine trace elements and their bioavailable forms by the use of the ICP-AES method. The contents of Al, B, Ba, Bi, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, P, Pb, Se, Si, Ti, V and Zn were determined. The total concentrations were measured in samples mineralised with concentrated nitric acid and hydrogen peroxide in a microwave system. The one-step extraction was applied, using, as extractants: deionised water, diluted hydrochloric acid and buffer solution containing pepsin. Efficiencies of the leaching versus time were investigated. The extraction efficiencies were analysed, taking into account bioavailability of elements under conditions simulating digestion processes in the alimentary system. The contents of the examined elements in prescribed amounts of medication, were compared to the nutritional requirements and daily permissible dose. The results are considered in terms of the utility of the natural herbal medicaments as a source of minerals indispensable for proper functioning of the human organism. Some points of merit (precision of measurements, accuracy by Standard Reference Material analysis) are also considered.  相似文献   

17.
Fine particles emitted from vehicles have adverse health effects because of their sizes and chemical compositions. Therefore, this study attempted to characterize the metals in nano (0.010 < Dp < 0.056 microm), ultrafine (Dp < 0.1 microm), fine (Dp < 2.5 microm), and coarse (2.5 < Dp < 10 microm) particles collected near a busy road using a microorifice uniform deposition impactor (MOUDI) and a Nano-MOUDI. The nano particles were found to contain more of traffic-related metals (Pb, Cd, Cu, Zn, Ba, and Ni) than particles of other sizes, although crustal metals accounted for over 90% of all the particulate metals. Most crustal metals, Ba, Ni, Pb, and Zn in ultrafine particles displayed Aitken modes due to their local origins. The Ag, Cd, Cr, Ni, Pb, Sb, V, and Zn were 37, 50, 28, 30, 24, 64, 38, and 22% by mass, respectively, in < 0.1-microm particles, with submicron mass median diameters (MMDs) in PM(0.01-18) (except Zn) (particularly the < 0.1-microm MMDs for Cd and Sb). These levels raise potential health issues. Particle-bound Zn was more abundant in the accumulation mode than in the nucleation/condensation mode, but the opposite was true for Ag, Cd, and Sb. The Ag, Ba, Cd, Pb, Sb, V, and Zn contents in nano particles were strongly associated with diesel fuel, while the Cu, Mn, and Sr in particles < 0.1 microm were more strongly associated with gasoline. The high content of Si in nano particles, more associated with diesel soot than with gasoline exhaust, is another health concern.  相似文献   

18.
研究采用螯合剂及超滤技术脱除岩藻聚糖中重金属元素的方法。在提取岩藻聚糖工艺中添加不同浓度的EDTA 二钠和植酸溶液,对所制备的岩藻聚糖采用电感耦合等离子体- 质谱技术(ICP-MS)及氢化物- 原子荧光光谱法(HGAFS)检测其Mg、Ca、Fe、Mn、Cu、Zn、Ag、Cd、Ba、Pb、As、Hg 元素的含量。研究表明,在提取工艺中加入1.0 × 10-2mol/L EDTA 二钠可以有效地降低岩藻聚糖中Mg、Ca、Mn、Zn、As、Ag、Cd、Pb等元素的残留量,但没有减少Hg、Fe、Cu、Ba 元素的残留量;而提取工艺中加入0.10mol/L 植酸仅对减少Ag、Cd 和Zn 元素的残留量有一定的效果。通过对岩藻聚糖进行As、Hg 富集处理,研究在酸处理后采用超滤脱除重金属元素的效果,结果表明,各实验组均未检出As 元素,但对Hg 元素没有效果。因此,在提取岩藻聚糖的工艺中添加一定浓度的EDTA 二钠或在纯化过程中经酸处理后采用超滤脱除技术均可显著减少岩藻聚糖制品中重金属元素的残留量,从而制备高质量的岩藻聚糖。  相似文献   

19.
A method for the determination of Na, K, Ca, Mg, P, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn levels in high saline food products (instant soups and seasoning mixtures) using ICP–OES was developed. The results of the direct determination with multi-elemental water standards were compared with the internal standardisation, the standard addition methods and the allowable limits of the above mentioned elements in food. The method was shown to be sensitive with limits of detection: Na 1.50, K 12, Ca 0.32, Mg 0.13, P 1.1, Cd 0.16, Cr 0.21, Cu 0.32, Fe 0.30, Mn 0.17, Ni 0.42, Pb 2.1 and Zn 0.21 (in mg kg−1). The method exhibited RSD 2–8%.  相似文献   

20.
Precipitation of Ca phosphates, an important process in controlling P stability and activity in P-fertilized soils and P-rich wastewater, is often affected by other components. The purpose of this study was to document interactive effects of CO3(2-) and Mg2+ on Ca phosphate precipitation under conditions simulating (i) dairy manure-amended soil leachate (system I; pH 7.1) and (ii) P recovery from flushed dairy manure wastewater (system II; pH 9.2). Hydroxyapatite (HAP) and more soluble amorphous Ca phosphate (ACP) were formed in the control solutions of system I and system II, respectively. Carbonate only slightly affected the crystallinity of the precipitate, but significantly reduced the precipitation rate via CO3(2-) competition for PO4(3-) (system I) or preemptive CaCO3 precipitation (system II). Magnesium severely inhibited both precipitate crystallinity and precipitation rate, allowing formation of ACP in both systems, presumably due to Mg2+ incorporation into the Ca phosphate structure to form Mg2+ -substituted structure that crystallized to whitlockite upon heating. Coexistence of CO32- and Mg2+ in system I showed a synergistic inhibitory effect, compared to their individual presence, probably because both CO3(2-) and Mg2+ were incorporated into the precipitate. However, in system II, the individual inhibitory effect of CO3(2-) or Mg2+ was eliminated when both were present. The likely mechanism involves formation of aqueous MgCO3 (aq) which reduces free CO3(2-) and Mg2+ activities, resulting in less preemptive CaCO3 formation and enhanced Ca phosphate precipitation.  相似文献   

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