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1.
协同—络合萃取法回收含酚废水中的酚类   总被引:2,自引:0,他引:2  
葛宜掌  金红 《环境化学》1996,15(2):112-117
在现有的各种收处理高浓度含酚废水的方法中,溶剂萃取法最为有效,但现有常用脱酚萃取剂分别存在着萃取效能低等诸多缺点,萃残液中一般尚存有几十至几百mg.l^-1的酚类,本文提出了协同-络合萃取法,并按该法原理研制HC-1-HC-4四类新型协同-络合萃取剂,其中HC-3和HC-4对苯酚稀溶液的萃取平衡常数分别为KHC-3=612.4和KHC4=483.7,单级萃取可将两组中高浓度的含酚废水中酚浓度降至1  相似文献   

2.
本研究以锌镀层退底废液中锌配备顺收为例探讨从盐酸体系中分离酸-金属的工艺特点,选取了高效又价廉的国产萃取剂(N-235)和反萃剂(生石灰),建立了新的回收处理工艺路线,中试结果证明此工艺在技术上和设备上是可行的。  相似文献   

3.
白光月  王玉洁 《环境化学》1994,13(4):323-327
用乙基纤维素作膜材将三辛胺(简称TOA)微胶囊化,用于萃取酸性水溶液中的Cr2O7^2-离子。通过搅拌法萃取实验表明,TOA被微胶囊化后对铬离子仍具有较高的萃取速度,实验测定渗透系数为6.78×10^-6m/min,并能有效地防止乳化现象。将微胶囊制备成填充柱对Cr2O7^2-进行萃取实验。对外相水的流速、微胶囊粒径、柱的重复使用次数与萃取容量的关系进行了研究。当粒径为100-200μm,流速为3  相似文献   

4.
超高浓度萘系磺酸染料中间体废液资源化   总被引:1,自引:0,他引:1  
本文介绍了胺盐萃取回收率液中萘磺酸染料中间体的方法,回收率达95%以上,回收浓缩液工艺套用,10t/d废液量的资源化年净效益达580万元,投资费用两个月即可全部收回,采用Langmuir等温方程描述体系中萃取剂用量,待萃物含量和萃取率的关系,使工艺参数的确立和工程设计完全处理指导之下。  相似文献   

5.
陈树榆  张敏 《环境化学》1995,14(2):169-173
本文建立了一个流动注射在线萃取-火焰原子吸收测定人发中微量镉和铅的方法,对含Cd和Pb分别为0.02μg/ml和0.20μg/ml的溶液,其相对标准偏差分别为3.4%和3.8%(n=9),Cd和Pb的灵敏度分别提高21倍和23倍,分析速度达36次/h,Cd和Pb的回收率分别在87.3%-97.0%和91.9%-107.3%之间,文中还详细研究了各种实验参数的选择,测定人发样的结果与文献值相符。  相似文献   

6.
周黎明  顾惠芬 《环境化学》1995,14(5):449-453
本文对水样中的塔崩及其降解产物磷酸乙酯的提取方法进行了研究,试验了不同的萃取剂及萃取时溶液的pH值,优化了萃取条件,在pH=9时,二氧甲烷萃取塔崩的回收率较高,三次测定的变异系数小于3.0%,用气相色谱-质谱(EI方式)法测定了水样中的塔崩和磷酸乙酯。  相似文献   

7.
酸化—吹气—吸收法测定水及废水中的硫化物   总被引:1,自引:0,他引:1  
文志明  林大泉 《环境化学》1994,13(2):170-175
本文设计了硫化物测定的酸化-吹气-吸收装置,验证了装置对硫化的回收效果,对硫化物标准溶液的配制及其稳定性进行了研究,对分析条件进行了最佳选择,建立了亚甲基监光度法测定硫化物的分析方法,并对实际样品进行了测定。本方法的检出限为0.005mgS^2-/l,线性范围为0.005-0.700mgS^2-/l,可应用于水和废水样品中微量硫化物的测定。  相似文献   

8.
从土样中筛选得到20支可将富马酸转化为L-苹果酸垢细菌菌株。经摇瓶复筛,得到一株富马酸酶活力较高的ZG-4菌株。以改性PVA为载体,制备得到固定化细胞。其较佳转化条件为:1经mol/L Na2Fu为底物,pH7.0,40转化。固定化细胞经胆酸ρ=4g/L或TPCρ=0.6g/L预处理后,可有效抑制琥铂酸副产物的生成。添加没食子单宁ρ=1gL,可使富马酸酶比活力达1.95mmol g^-h^-。固定  相似文献   

9.
研究表明Ce^3+在pH〈6.2KCl介质中以254.0nm紫外光激发时,在352.0nm处发出具有恒定强度的荧光。因而可选择pH5-6作为测定酸度条件,利用Al2(SO4)3消除Fe^3+等离子的干扰,建立起Ce^3+的流动注射荧光分析法。方法的线性范围是2.0×10^-7—2.0×10^-6mol/l,一元回归方程△F=663600C-0.041(n=10,r=0.9997),检测限6.0×1  相似文献   

10.
罗孟飞  朱波 《环境化学》1996,15(3):193-198
本文考察了An-Mn,Ag-Co和Ag-Ce复合氧化物上CO,丙酮和吡啶的催化氧化性能,结果表明,双组分Ag-Mn/Al2O3和Ag-Co/Al2O3催化剂的氧化活性均高于单组分Ag/Al2O3.在Ag-Ce/Al2O3催化剂上,CO氧化反应的速率言程可用r=kPo2^mPCO来表示,随着催化剂中氧化铈含量的增加,对氧的反应级数明显下降。  相似文献   

11.
The leather industry uses conventional tanning methods which cause environmental pollution due mainly to the presence of chromium. This study suggests a treatment for solid leather waste containing chromium as an ecological alternative to the pollution generated by tanneries. The study uses an original approach to the optimisation of chromium recovery by mathematical and statistical treatment of the experimental data. Several factors that influence recovery, such as temperature, concentration, time and solid/liquid ratio through acid and basic hydrolysis were analysed with the aid of experimental design. Tanning liquor was obtained by adjusting pH, alkalinity and concentration when hydrolysis finished. An appropriate response surface model was constructed using alkaline hydrolysis experiments with sodium hydroxide, leading to conditions for maximum recovery of Cr2O3. The optimal NaOH concentration (1.58%), temperature (63.7 °C), time (3 h) and solid/liquid ratio (1/70 g·mL?1) were established. The results indicate that sodium hydroxide as an hydrolysis agent is a highly efficient means of recovering chromium from solid leather waste in order to produce tanning liquor.  相似文献   

12.
Liming materials have been used to immobilize heavy metals in contaminated soils. However, no studies have evaluated the use of eggshell waste as a source of calcium carbonate (CaCO?) to immobilize both cadmium (Cd) and lead (Pb) in soils. This study was conducted to evaluate the effectiveness of eggshell waste on the immobilization of Cd and Pb and to determine the metal availability following various single extraction techniques. Incubation experiments were conducted by mixing 0-5% powdered eggshell waste and curing the soil (1,246 mg Pb kg?1 soil and 17 mg Cd kg?1 soil) for 30 days. Five extractants, 0.01 M calcium chloride (CaCl?), 1 M CaCl?, 0.1 M hydrochloric acid (HCl), 0.43 M acetic acid (CH?COOH), and 0.05 M ethylendiaminetetraacetic acid (EDTA), were used to determine the extractability of Cd and Pb following treatments with CaCO? and eggshell waste. Generally, the extractability of Cd and Pb in the soils decreased in response to treatments with CaCO? and eggshell waste, regardless of extractant. Using CaCl? extraction, the lowest Cd concentration was achieved upon both CaCO? and eggshell waste treatments, while the lowest Pb concentration was observed using HCl extraction. The highest amount of immobilized Cd and Pb was extracted by CH?COOH or EDTA in soils treated with CaCO? and eggshell waste, indicating that remobilization of Cd and Pb may occur under acidic conditions. Based on the findings obtained, eggshell waste can be used as an alternative to CaCO? for the immobilization of heavy metals in soils.  相似文献   

13.
Green liquor dregs is the biggest waste fraction at sulphate pulp mills. It is commonly landfilled. Here we demonstrate that the utilization of green liquor dregs as a neutralizing agent for acidic wastewaters is a potential alternative and an environmentally friendly method in contrast to its landfill disposal. The liming effect value of 39.6% for green liquor dregs, expressed as Ca equivalent, is similar to the liming effect value of 38% of a commercial limestone product. In addition, the pH value of 10.7 indicates a strong liming effect.  相似文献   

14.
The leaching characteristics of heavy metals in products of cement stabilization of fly ash from a municipal solid waste incinerator were investigated in this paper. The stabilization of heavy metals such as Cd, Pb, Cu, and Zn in fly ash from such incinerators was examined through the national standard method in China based on the following factors: additive quantity of cement and Na2S, curing time, and pH of leaching liquor. The results showed that as more additives were used, less heavy metals were leached except for Pb, which is sensitive to pH of the leachate, and the worse effect was observed for Cd. The mass ratio of cement to fly ash = 10% is the most appropriate parameter according to the national standard method. When the hydration of cement was basically finished, stabilization of heavy metals did not vary after curing for 1 d. The mixtures of cement and fly ash had excellent adaptability to environmental pH. The pH of leachate was maintained at 7 when pH of leaching liquor varied from 3 to 11.  相似文献   

15.
LFG控制利用工程基本参数的试验研究   总被引:5,自引:0,他引:5  
通过深圳市玉龙坑垃圾填埋场的现场抽气试验。本文进行了填埋气本安全控制与回收利用工程基本参数的研究。  相似文献   

16.
Catalase activity of mixed liquor suspended solids of aeration tank of activated sludge plants in Milwaukee, WI, was measured in sonicated samples. Catalase activity varied in the samples of mixed liquor suspended solids collected from the head and end of the aeration tanks; in return activated sludge; and in waste activated sludge. Catalase activity decreased in mixed liquor suspended solids, on prolonged aeration (8 days), in the absence of added sewage. Volatile suspended solids and catalase activity seemed to bear a relationship.  相似文献   

17.

The adverse effects of climate change calls for the rapid transformation of manufacturing processes to decrease the emissions of carbon dioxide. In particular, a lower carbon footprint can be achieved by capturing carbon dioxide at the site of emission. Here we review the use of industrial effluents, waste and residues to capture carbon dioxide. Waste include steelmaking slag, municipal solid waste incinerator ashes, combustion fly ash, black liquor, paper mill waste, mining waste, cement waste, construction and demolition waste, waste from the organic industry, and flue gas desulfurization gypsum waste. Capture capacities range from 2 to 800 kg of carbon dioxide per ton of waste, depending on processes, waste type and conditions. Cement waste and flue gas desulfurization gypsum waste show the highest capture capacity per ton of waste.

  相似文献   

18.
● Au, Ag and Pd were recovered from WPCBs with high efficiencies. ● Au leaching is strictly dependent on WPCB size and reagent concentration. ● High Ag extraction efficiencies are achieved regardless of the WPCB size. ● Pd leaching works better with small and medium WPCB sizes. ● The leaching results suggest the possibility of selective recovery of metals. The work presented here focused on the extraction of gold (Au), silver (Ag) and palladium (Pd) from electronic waste using a solution of ammonium thiosulfate. Thiosulfate was used as a valid alternative to cyanide for precious metal extractions, due to its non-toxicity and high selectivity. The interactions between sodium thiosulfate, total ammonia/ammonium, precious metal concentrations and the particle size of the waste printed circuit boards (WPCBs) were studied by the response surface methodology (RSM) and the principal component analysis (PCA) to maximize precious metal mobilization. Au extraction reached a high efficiency with a granulometry of less than 0.25 mm, but the consumption of reagents was high. On the other hand, Ag extraction depended neither on thiosulfate/ammonia concentration nor granulometry of WPCBs and it showed efficiency of 90% also with the biggest particle size (0.50 < Ø < 1.00 mm). Pd extraction, similarly to Au, showed the best efficiency with the smallest and the medium WPCB sizes, but required less reagents compared to Au. The results showed that precious metal leaching is a complex process (mainly for Au, which requires more severe conditions in order to achieve high extraction efficiencies) correlated with reagent concentrations, precious metal concentrations and WPCB particle sizes. These results have great potentiality, suggesting the possibility of a more selective recovery of precious metals based on the different granulometry of the WPCBs. Furthermore, the high extraction efficiencies obtained for all the metals bode well in the perspective of large-scale applications.  相似文献   

19.
本研究建立气相色谱/质谱来测定电子垃圾拆解区土壤中四溴双酚 A(TBBPA)的方法。该化合物通过超声波辅助萃取,溶剂选择V(丙酮)﹕V(正己烷)=1﹕1或乙酸乙酯;净化柱选择酸化的氟罗里硅土和无水硫酸钠混合物或CleanertC18-SPE进行净化;净化液浓缩后经衍生反应,衍生试剂选用N,O-双(三甲基硅烷基)三氟乙酰胺(BSTFA)和含1%的三甲基氯硅烷(TMCS)。该方法测定电子垃圾拆解区土壤中TBBPA的检出限为(S/N=3)0.1μg·kg^-1加标回收率平均值为92.7%(n=5),重现性RSD为2.52%(n=5);线性范围是20~400μg·kg^-1相关系数0.999。该方法用于调查电子垃圾拆解区土壤中四溴双酚A,范围值为5.17~218.00μg·kg^-1其周围农田土壤中四溴双酚A,范围值为0.312~4.170μg·kg^-1  相似文献   

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