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1.
通过FTIR、SEM、XPS、zeta电位和粒度测试研究了双梳型共聚物AgrilanTM 752对吡虫啉悬浮剂分散稳定性的影响。结果表明AgrilanTM 752分子中存在羧基、酯基和聚氧乙烯醚侧链,通过氢键、范德华力和疏水作用力结合吡虫啉,从而有效地分散吡虫啉颗粒;AgrilanTM 752用量与悬浮剂的分散稳定性密切相关,实验条件下得出其最佳用量为3%(质量分数),此用量下AgrilanTM 752的吸附层厚度和zeta电位负值最大;初始pH值超过6后AgrilanTM 752的吸附层厚度逐渐降低,zeta电位在初始pH=10处存在最大负值,初始pH值在2~10范围内悬浮hina剂的分散稳定性普遍较高,pH值超过10后分散稳定性明显降低;电解质离子(Na+、Mg2+和Ca2+)浓度越高则AgrilanTM 752的吸附层厚度和zeta电位负值越低,悬浮剂的分散稳定性越差,相同浓度下电解质离子对悬浮剂的分散稳定性影响程度顺序为Ca2+Mg2+Na+。  相似文献   

2.
为降低离子对聚合物溶液黏度的影响,研究了K+、Na+、Ca2+、Mg2+、Fe2+、Fe3+、S2-离子溶液对聚合物黏度的影响规律。研究表明,二价阳离子的影响比一价阳离子的影响大,阳离子中Fe2+的影响最大,阴离子中S2-的影响最大。随着阳离子K+、Na+、Ca2+、Mg2+浓度增加聚合物溶液黏度降低,当K+、Na+、Ca2+、Mg2+离子质量浓度分别为40,1 000,60,50 mg/L时对母液黏度稳定性影响最大,此时1 500 mg/L聚合物溶液黏度降到110 mP·s。因此,对于油田选用配聚用水时,需要严格控制Fe2+和S2-的出现并保证K+、N...  相似文献   

3.
通过快速氯离子迁移系数法(RCM法)和自然扩散法研究了钾、钠、钙、镁四种阳离子类型的氯盐对粉煤灰混凝土氯离子扩散性能的影响,基于分子动力学模拟,对比分析了K+、Na+、Ca2+、Mg2+、Cl-五种离子在水溶液中的径向分布函数和均方位移曲线。结果表明:粉煤灰混凝土的氯离子扩散系数主要受阳离子价态的影响,价态越高,扩散系数越大;扩散系数随着氯离子浓度增加先增大后减小,随着粉煤灰掺量增加先减小后增大;阳离子类型影响氯离子扩散性能的原因是离子扩散能力不同,其中各离子水合能力强弱顺序为Mg2+>Ca2+>Na+>K+>Cl-,自扩散系数大小顺序为Mg2+>Ca2+>Cl->K+>Na+。MgCl2中的Mg2+和Cl-对粉煤灰混凝土都有侵蚀作用,且Mg2+会抑制粉煤灰活性的激发。  相似文献   

4.
分子筛对重金属废水吸附性能的实验研究   总被引:1,自引:0,他引:1  
为验证分子筛对重金属废水的处理效果,以实际含锰废水为研究对象,采用13X分子筛,通过实验研究了吸附材料用量、吸附时间、搅拌转速和溶液pH对Ca2+、Mn2+、Mg2+吸附效果的影响。结果表明:吸附材料用量增加对Mn2+、Mg2+的吸附影响较大;随着吸附时间增长,各金属离子去除率增加;适当的转速有利于金属离子的吸附,但各金属离子对应的最佳转速各不相同;pH提高,能够促进分子筛对金属离子的吸附。13X分子筛对金属离子的吸附机理为离子交换吸附和表面吸附。研究表明,13X分子筛在处理低浓度含锰重金属废水方面表现出良好的应用前景。  相似文献   

5.
为了寻求性能良好的环保型吸附剂,用于去除海水中重金属Cu(Ⅱ),以柚子皮对Cu(Ⅱ)的吸附率和吸附容量为指标,研究不同质量浓度的氢氧化钠和柠檬酸对柚子皮改性后的吸附效果,并探究反应时间、反应温度、pH值、海水中共存主要金属离子(Na+、Ca2+、Mg2+)、Cu(Ⅱ)浓度与柚子皮用量对改性柚子皮吸附海水中Cu(Ⅱ)性能的影响。实验结果表明:柚子皮被5%柠檬酸改性后的吸附率较好,比未改性柚子皮对Cu(Ⅱ)的吸附率高出约一倍;当Cu(Ⅱ)质量浓度为10 mg/L时,在反应温度为25℃、吸附时间为60 min、改性柚子皮投加量10.0 g/L时,改性柚子皮对Cu(Ⅱ)的吸附效果比较好,吸附率为97.0%;随着Na+、Mg2+、Ca2+质量浓度的变大,改性柚子皮对Cu(Ⅱ)的吸附率减小,但减少幅度不大,仍均保持在90%左右,说明改性柚子皮可以很好地用于海水中Cu(Ⅱ)去除,对于取样于天津附近海水中的Cu(Ⅱ),平均吸附率可达83.03%。  相似文献   

6.
矿物表面性质是影响其分散聚集和浮选行为的主要因素,通过溶液化学分析计算、浊度、接触角及Zeta-电位测试分析,研究了矿浆中,Mg2+,Al3+,Fe3+等金属离子对氟磷灰石(FAP)表面性质的影响。结果表明:金属离子在溶液中的存在形式随pH值的变化而改变,FAP是亲水性矿物,添加Fe3+对FAP的润湿性影响受pH的影响较大,在酸性环境中,Fe3+对FAP的亲水起促进作用,在中性及碱性环境下,Fe3+能较好地抑制FAP的亲水。Mg2+和Al3+受pH的影响较小,在中性环境下Mg2+,Al3+离子均抑制FAP的润湿性。在pH=3~11范围内,Mg2+主要以+2价的离子存在,压缩FAP表面双电层;Al3+和Fe3+主要是通过水解的作用生成氢氧化物沉淀覆盖在FAP表面,并且Mg2+,Al  相似文献   

7.
利用变异系数分析、Stiff图分析及Piper图分析等方法综合研究了某煤矿内矿井水的化学特征。评价结果表明,该工区内大部分地层水表现为溶液中阳离子Ca2+、Mg2+含量均显著低于(K++Na+)含量。该类地层水主要包括了太灰水、煤系砂岩水、老空水和新生界水,前三者均具有较高的溶液TDS值,而新生界水的样本结果普遍表现出较低的TDS值。地层水中阳离子Ca2+、Mg2+的来源较为复杂,其中硫酸盐岩和硅铝酸盐岩类矿物的溶解占比较大,而碳酸盐类矿物的溶解占比较小;这两种阳离子与Na+存在阳离子交换,进而导致水溶液中阴离子Cl-的含量明显低于阳离子Na+。煤矿井水化学特征演化的研究可为矿区安全生产提供依据。  相似文献   

8.
邹啁 《辽宁化工》2022,(11):1505-1508
采用高温高压稠化法在稳态剪切条件下模拟凝胶溶液自井口注入地层时的升温加压过程,研究高温高压下成胶环境即溶液初始p H值、温度、金属盐离子对PAM/PEI体系的凝胶化过程和成胶强度的影响。通过高温高压稠化曲线,可将高温高压下PAM/PEI体系的凝胶化过程分为诱导期、加速反应期、平衡期3个阶段。结果表明:引入H+改变凝胶溶液初始p H值,发现凝胶溶液初始黏度先增加后降低,体系可在碱性和中性条件下稳定成胶,而在酸性条件下,体系无法凝胶化。凝胶体系中引入Na+、Ca2+后,成胶时间被不同程度的延长,且Ca2+对凝胶体系的影响远大于Na+。体系中Na+质量浓度增加,其缓交联作用有限,且不会大幅度降低凝胶成胶强度;Ca2+质量浓度增加,凝胶成胶时间明显延长,但其对凝胶成胶强度影响较大,Ca2+质量浓度过高,会导致凝胶脱水。  相似文献   

9.
地矿样品中硼的测定难点在于既要将样品完全分解还不能造成硼的损失,本文选择强碱过氧化钠(Na2O2)作为熔剂能够完全有效地分解样品。碱熔带入试液中大量的钠会影响仪器测定,采用强酸性阳离子交换树脂,在振荡器上交换吸附溶液中Na+,降低试液含盐量,减小Ca2+、Mg2+、Al3+、Fe3+、K+等阳离子的干扰,同时也可以降低溶液的pH值到中性。使用柠檬酸溶液络合试液中的重金属离子,进一步降低基体干扰。使用电感耦合等离子体发射光谱仪(ICP-OES)进行测定。通过实验,选择出合适的分析谱线,确定最佳的树脂用量和交换吸附时间。对国家标准物质和地矿样品进行测定,确定方法的检出限为50μg·g-1,相对标准偏差(RSD,n=7)为1.90%~8.36%,相对误差为-1.67%~5.20%。与其他测试方法进行比对,测定结果没有明显偏差。  相似文献   

10.
采用UV/Na2CO5技术去除水中24种咪唑类离子液体,探究了过碳酸钠(Na2CO5)浓度、不同初始pH、无机离子种类、腐殖酸(HA)浓度和不同真实水体等对降解的影响,并通过自由基淬灭实验推断了反应体系中起作用的自由基。实验结果表明,24种咪唑类离子液体的光降解均符合假一级动力学,但光降解速率常数与其自身结构性质未呈现明显相关性。离子液体的光降解速率随着Na2CO5浓度的升高而增加,当Na2CO5与1-辛基-3甲基咪唑溴盐(IL-5)的摩尔浓度比为10:1时,IL-5在5 min之内几乎可以100%被降解。反应体系的pH对IL-5的降解有重要影响,当pH=8时,IL-5的降解速率常数最高,为0.011 4 s-1。Na+、K+、Ca2+、Mg2+和Cl-对IL-5的光降解无影响,SO...  相似文献   

11.
Recovery of alginate extracted from aerobic granular sludge (AGS) has given rise to a novel research direction. However, these extracted alginate solutions have a water content of nearly 100%. Alternately, ultrafiltration (UF) is generally used for concentration of polymers. Furthermore, the introduction of multivalent metal ions into alginate may provide a promising method for the development of novel nanomaterials. In this study, membrane fouling mitigation by multivalent metal ions, both individually and in combination, and properties of recycled materials were investigated for UF recovery of sodium alginate (SA). The filtration resistance showed a significantly negative correlation with the concentration of metal ions, arranged in the order of Mg2+ < Ca2+ < Fe3+ < Al3+ (filtration resistance mitigation), and the moisture content of recycled filter cake showed a marked decrease. For Ca2+, Mg2+, Fe3+, and Ca2++Fe3+, the filtration resistances were almost the same when the total charge concentration was less than 5 mmol·L-1. However, when the total charge concentration was greater than 5 mmol·L-1, membrane fouling mitigation increased significantly in the presence of Ca2+ or Fe3+ and remained constant for Mg2+ with the increase of total charge concentration. The filtration resistance mitigation was arranged in the order of Fe3+ > Fe3+ + Ca2+ > Ca2+ > Mg2+. Three mechanisms were proposed in the presence of Fe3+, such as the decrease of SA concentration, change in pH, and production of hydroxide iron colloids from hydrolysis. The properties of recycled materials (filter cake) were investigated via optical microscope observation, dynamic light scattering, Fourier transform infrared, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy. The results provide further insight into UF recoveries of alginate extracted from AGS.  相似文献   

12.
针对饱和卤水直接制碱过程需要去除硫酸根、钙离子、镁离子(SO42-、Ca2+、Mg2+)等杂质离子的问题,探索了利用纳滤膜分离精制饱和卤水新工艺。通过考察NF270、DL2540、ESNA1 3种类型纳滤膜的透过通量和离子截留率,确定了选用DL2540为实验用膜;分析了DL2540纳滤膜对离子的截留性能和对盐田饱和卤水的分离性能及其对饱和卤水精制的效果。结果表明,增加同离子浓度、降低压力有利于不同价态阳离子、阴离子间的分离,DL2540纳滤膜对盐田饱和卤水中SO42-、Ca2+、Mg2+截留率分别达到95%以上、30%~50%、30%~70%,对Na+、Cl-截留率均低于15%,进一步证明DL2540纳滤膜具有较好的稳定性和二价离子截留效果,在饱和卤水精制上展示出较好的应用前景。  相似文献   

13.
The objective of this study was to evaluate the use of cheap carbon-based adsorbents from sewage sludge pyrolysis to remove Na+, K+, Ca2+ and Mg2+ from saline water. Four model solutions of NaCl, KCl, CaCl2 and MgCl2 that simulated seawater composition were used. The model solutions were 456.54 mmolc L−1 NaCl, 9.72 mmolc L−1 KCl, 19.96 mmolc L−1 CaCl2 and 111.09 mmolc L−1 MgCl2. Two carbon adsorbents, one with chemical activation, were prepared by a new method and evaluated for ion adsorption. The results indicated that carbon adsorbent without chemical activation was the most effective in removing ions from different solutions and the removal of metals followed the sequence: Na+ (76.78−69.66) >K+ (66.0−57.80) >Mg2+ (44.84−42.85) >Ca2+ (35.12−12.38). Results showed that it is to possible prepare carbon-based adsorbents from sewage sludge following inexpensive and environmentally acceptable methods.  相似文献   

14.
Eu3+ ion was adopted as a probe to detect the probability of entrance of alkali elements into the crystal lattice of MgO, CaO and La2O3 by means of its characteristic emission. Based on the experimental data it is concluded that Li+ and Na+ ions can substitute Mg2+ and Ca2+ ions and only a small amount of K+ ion can enter into the lattice of CaO. Whilst Li+ ion can not enter into the lattice of lanthana. The conclusion of this investigation is in good agreement with that obtained by Lunsford by ESR studies.  相似文献   

15.
通过自然蒸发实验,对鸭湖背斜构造深部卤水进行了研究,得到了该卤水在自然蒸发过程中各元素富集规律及析盐规律。受高含量钙影响,卤水蒸发路线在K+,Na+,Mg2+∥Cl--H2O(25℃)介稳相图中偏移比较明显,可与Na+,K+,Mg2+,Ca2+∥Cl--H2O(25℃,对NaCl饱和)介稳相图相结合对实验数据进行分析。卤水自然蒸发过程中矿物析出顺序为:石膏→石盐→光卤石→南极石→溢晶石;光卤石产量较小并且质量不高;锂最终浓缩至质量浓度约为2.9 g/L时,硼、锶、溴、碘、铷、铯等微量元素均有析出。实验数据和结论为针对该类型卤水进行更深入的综合开发利用研究提供了依据,如前期除钙后梯度提取硼酸、碳酸锂、溴素等产品。  相似文献   

16.
目前,开发绿色高效的重金属吸附材料受到人们的广泛关注。以硅藻土为原料,经水热法选择性地制备了2类硅酸盐材料即麦羟基硅钠石和方沸石。吸附测试结果表明,麦羟基硅钠石层间的钠离子能够与锂离子、镁离子、锌离子、钴离子、镍离子、铜离子等进行阳离子交换且能保持层状母体框架的稳定性。以钴离子、镍离子为例深入研究其吸附动力学和吸附机制发现,钴离子和镍离子的嵌入分别将麦羟基硅钠石的层间距由本征的1.56 nm减小到0.24、0.23 nm;室温下,对钴离子、镍离子的最大吸附量分别可达45、39 mg/g,均符合Langmuir单层吸附模型;钠离子的置换量大约是吸附的钴离子、镍离子量的两倍,证实层间离子交换主导吸附化学过程。因此,麦羟基硅钠石材料在多金属硅酸盐功能材料的合成以及环境吸附净化领域具有较大的应用潜力。  相似文献   

17.
分别用3-氨基-1,2-丙二醇(3-APD)和2-氨基-1,3-丙二醇(2-APD)对多孔氯甲基聚苯乙烯树脂(CMPS)进行修饰,制备得到含邻、间位二羟基官能团的硼螯合树脂:PS-3-APD和PS-2-APD。用傅里叶红外光谱仪(FTIR)、元素分析仪(EA)、压汞仪(MIP)和激光粒度仪(LPS)对材料进行表征,确认功能单体成功接枝于氯球上。对两种树脂进行了静态提硼性能研究,分别考察了原料液pH、初始硼酸浓度、外来金属离子对硼酸吸附量的影响,当溶液pH为9.15~9.20时,两种树脂对硼酸吸附量最大;溶液中Na+、Mg2+、Ca2+的存在会一定程度削弱树脂对硼酸吸附性能。吸附动力学表明其吸附速率较快,且均满足准二级动力学模型。与Freundlich相比,吸附等温线更符合Langmuir模型,拟合得到的理论最大吸附量分别为0.730mmol/g和0.868mmol/g。本文对未来新型硼螯合树脂的开发及工业化应用提供参考和指导。  相似文献   

18.
In this paper, the influence of two typical ionic impurities (Na+ and Mg2+) is investigated with the focused beam reflectance measurement (FBRM) technique. In this system, the on-line FBRM is used as a tool for monitoring the crystallization process of cobalamin by measuring the chord length distribution of particles and the particle counts. It is noted that impurity Mg2+ has a more significant effect than Na2+ in crystal growth of the whole crystallization process. From the microscopic observation of crystals, Mg2+ has an obvious effect on the crystal habit, while Na2+ has little effect. In addition, the crystal habit changes can be monitored by particle vision measurement (PVM). Understanding these effects is helpful to aid optimization and improve process control.  相似文献   

19.
The separation of Ca2+ and Mg2+ ions from phosphoric acid-nitric acid aqueous solution is very significant for the neutralization process of nitrophosphate fertilizer. This paper studied the adsorption equilibrium, kinetics, and dynamic separation of Ca2+ and Mg2+ ions by strong acid cation resin, and the effects of phosphoric acid and nitric acid on the adsorption process were investigated. The results reveal that the adsorption process of Ca2+ and Mg2+ ions in pure water on resin is in good agreement with the Langmuir isotherm model and their maximal adsorption capacities are 1.86 mmol·g-1 and 1.83 mmol·g-1, respectively. The adsorption kinetics of Ca2+ and Mg2+ ions on resin fits better with the pseudo-first-order model, and the adsorption equilibrium in pure water is reached within 10 min contact time, while at the present of phosphoric acid, the adsorption rate of Ca2+ and Mg2+ ions on resin will go down. The dynamic separation experiments demonstrate that the designed column adsorption is able to undertake the separation of metal ions from the mix acids aqueous solution, but the dynamic operation should control the flow rate of mix acid solution. Besides nitric acid solution was proved to be effective to completely regenerate the spent resin and achieve the recyclable operation of separation process.  相似文献   

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