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《无机盐工业》2017,(2)
以内蒙古准格尔煤田煤矸石为原料,采用450℃低温碱融法对原料进行预处理,添加晶化导向剂,在原料配比为n(Na_2O)∶n(SiO_2)∶n(Al_2O_3)∶n(H_2O)=4∶2∶1∶123、晶化温度为50℃、晶化时间为24 h的水热合成条件下,制备了结晶度较高、平均粒径为2μm的4A分子筛。通过静态实验法测定了4A分子筛对罗丹明B的吸附特性,分析了吸附剂用量、初始浓度、溶液pH、吸附温度和吸附时间对吸附降解性能的影响。结果表明,当4A分子筛吸附剂加入量为7.5 g/L、罗丹明B初始质量浓度为0.5 mg/L、pH=8、吸附温度为50℃、吸附时间为2 h时,吸附率可达72.78%。该研究为4A分子筛的应用提供了重要的依据。 相似文献
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《现代化工》2017,(8)
采用共沉淀-煅烧法制备Mg-Al-Zr金属复合物,并用扫描电镜和X射线衍射对其进行表征,考察了吸附剂质量浓度、吸附时间、pH、初始氟质量浓度和共存阴离子对除氟影响。结果表明,在初始溶液pH=4~10,吸附剂质量浓度为3 g/L,氟初始质量浓度为40 mg/L时,对溶液中的氟去除效果最佳,吸附平衡时间为300 min。等温吸附数据分析显示其等温吸附特征可用Langmuir等温吸附方程描述,由其计算饱和吸附量为48.90 mg/g。共存阴离子对吸附材料除氟效率影响力大小为:PO_4~(2-)CO_3~(2-)SO_4~(2-)NO_3~-。吸附剂再生循环3次后,除氟效率仍在70%以上。 相似文献
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树脂吸附法回收焦化废水中的酚 总被引:7,自引:0,他引:7
通过静态吸附实验确定处理焦化废水中酚的最佳吸附树脂是NDA-99超高交联吸附树脂,并通过动态实验确定了树脂吸附法处理焦化废水中酚的最佳工艺条件是:pH为4.0,吸附流量为40mL/h,单柱废水处理量为300mL/批;在50℃下用10mL质量分数为8%的NaOH 10mL质量分数为4%的NaOH 20mL水脱附,流量为10mL/h;处理后废水中挥发酚质量浓度从1380mg/L降到12mg/L,COD从15500mg/L降到650mg/L。低浓度脱附液套用,高浓度脱附液用异丙醚萃取—蒸馏法回收杂酚,实现了焦化废水中酚的资源化。 相似文献
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以粉煤灰中的未燃炭粒(UC)和粉状活性炭(PAC)为吸附剂,研究对水体中残余煤油吸附性能。结果表明,UC和PAC的吸附过程符合Freundlich等温式和准2级反应动力方程,在吸附初期主要由边界层扩散为主,后期主要以微孔内扩散为主,并最终达到平衡状态。在搅拌转速190 r/min、吸附剂的质量浓度0.5 g/L时适宜吸附,且升温有利于吸附。对于初始煤油的质量浓度250 mg/L的水体,PAC在任何pH下,去除率都在70%以上;UC在pH=2时,吸附能力为佳,去除率为74.24%。AC能直接用于浮选废水处理,而UC需要进一步活化处理,提高吸附能力和适应性。 相似文献
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利用N-羧甲基壳聚糖吸附锰矿废水中Mn2+,通过考察吸附剂质量浓度、溶液pH、吸附温度及时间的影响,采用L16(45)正交试验确定吸附10.6 mg/L Mn2+废水的最佳工艺条件为:30.0 mg/m L N-羧甲基壳聚糖,在溶液pH=5.5、65℃下,振摇吸附8.5 h,Mn2+去除率99.1%,吸附后废水中Mn2+浓度0.095 mg/L,满足国家规定地表水锰含量要求,吸附过程符合Langmiur吸附特征,属于单分子层吸附。由于N-羧甲基壳聚糖吸附锰矿废水中Mn2+工艺简便、吸附效率高,从而可为相关行业的水污染处理提供理论基础。 相似文献
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采用氢氧化钠改性的硅藻土作为吸附材料,研究了吸附剂用量、搅拌时间、pH值以及废水浓度等因素对吸附效果的影响。结果表明,在100 mL Cu2+的质量浓度为10.49 mg/L,改性硅藻土投加量为3.5 g,pH值为8.5,吸附时间为30 min的条件下,废水中Cu2+的去除率最高可达97.93%,出水Cu2+的质量浓度低于0.22 mg/L,达到了GB 8978—1996《污水综合排放标准》一级标准的要求。 相似文献
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低温吸湿复合吸附剂的制备及吸湿性能 总被引:1,自引:0,他引:1
针对冷库结霜严重制约其经济性的问题,化学固体吸附除湿防霜技术逐渐得到重视。本文将对水吸附能力较强的金属卤化物与容易定型且传热传质性能较好的分子筛相结合,制成复合吸附剂,建立了低温情况下吸附材料的吸湿性能测试系统,并进行了大量测试,给出了多种材料在-5℃、-10℃、-15℃下的吸湿量及吸湿速率变化,实验结果表明复合吸附剂的吸附性能与单纯的分子筛相比有了明显的改善,13X型分子筛浸渍浓度20%的Na Br溶液所得试样吸湿量和吸湿速率性能优越,复合过程中损失较少,成本低,可作为复合吸附剂应用于冷库除湿系统中。 相似文献
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Friedel盐对废水中低浓度Cd2+的吸附动力学 总被引:1,自引:0,他引:1
以合成的Friedel盐(FS, 3CaO×A12O3×CaCl2×10H2O)为吸附剂,研究了FS去除废水中Cd2+的反应动力学和等温吸附特性. 考察了FS盐用量、温度及Cd2+初始浓度对Cd2+去除的影响. 结果表明,FS用量为0.03 g/L时,在室温下对废水中初始浓度为10 mg/L的Cd2+的去除率大于94.34%,吸附容量可达301.9 mg/g,吸附主要以离子交换吸附为主,最终形成Cd4Al2(OH)12Cl2(H2O)4×xH2O及Cd4Al2(OH)12Cl2×4H2O化合物. 利用一级动力学模型关联了反应动力学数据,得到速率常数k=0.049 min-1,吸附行为较符合Langmuir等温吸附方程. 相似文献
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为回收工业废气中的磷化氢(PH3)并资源化,采用浸渍法制备了一种CaCl2改性13X分子筛吸附剂,通过容积法研究了25—70℃PH3气体在改性13X分子筛上的等温吸附行为。结果表明,在实验条件范围内25,40,55,70℃下PH3的饱和吸附量(质量分数)分别为2.528,1.901,1.591,0.925mg/g。Freundlich吸附等温方程很好地模拟了改性13X分子筛对PH3的等温吸附,Langmuir和Henry吸附等温方程对吸附平衡数据的拟合效果不佳表明了改性13X分子筛表面吸附位的不均匀分布。当初始吸附量为0.10mg/g时,等量吸附热值最大,为17.81353kJ/mol,即等量吸附热不超过18kJ/mol,过程为物理吸附,便于PH3气体的解吸。 相似文献
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利用吸附等温线获得动力学参数,建立了CFD模型,模拟了氢气/氮气在结构化5A分子筛吸附床中的吸附过程,研究了吸附剂层片间距、吸附剂厚度等结构参数和吸附压力、进气流量等工艺参数对混合气吸附效果的影响。结果表明:减小层片间距和吸附剂厚度可显著提高传质系数和床层利用率。增大吸附压力可提高床层利用率,但会减小传质系数。进气流量对传质系数的影响不明显,但当流量较大时,吸附容量和床层利用率均呈减小趋势。结构化5A分子筛吸附剂吸附性能良好。 相似文献
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Air conditioning systems that are incorporating desiccant based dehumidifiers are finding increased applications over traditional vapor compression refrigeration systems due to their efficient handling of latent heat loads. Generally, silica gel, molecular sieves, or activated alumina coaled on a rotating honeycomb type desiccant matrix is used as a dehumidifier in these systems. However, shapes of the isotherm for water vapor adsorption on these materials are not favorable for optimal performance of desiccant cooling systems. Theoretical studies have shown that a material having a type I isotherm for water vapor, whose shape lies between that on molecular sieve 13X and silica gel would lower installation and operating costs of desiccant based air-conditioning systems.
An adsorbent was prepared by mixing a silica gel, molecular sieve 13X, and a hydrophobic molecular sieve. The mixed adsorbent was mixed with a binder and was further coated on both sides of a 0.0014“ thick aluminum foil. Both plain and corrugated foils were used in preparing a desiccant matrix. A plain sheet was inserted in between two corrugated sheets and then they were rolled into a cylinder. The shape of water adsorption isotherm and equilibrium water adsorption capacity were obtained for this desiccant matrix. The shape of the water isotherm in the temperature range of 288-308 K was found to be more favorable than that on silica gel or molecular sieve 13X. However, the total water adsorption capacity of the new mixed adsorbent was significantly lower than these materials. The water adsorption data on the mixed adsorbent could be correlated according to Polyani's potential theory 相似文献
An adsorbent was prepared by mixing a silica gel, molecular sieve 13X, and a hydrophobic molecular sieve. The mixed adsorbent was mixed with a binder and was further coated on both sides of a 0.0014“ thick aluminum foil. Both plain and corrugated foils were used in preparing a desiccant matrix. A plain sheet was inserted in between two corrugated sheets and then they were rolled into a cylinder. The shape of water adsorption isotherm and equilibrium water adsorption capacity were obtained for this desiccant matrix. The shape of the water isotherm in the temperature range of 288-308 K was found to be more favorable than that on silica gel or molecular sieve 13X. However, the total water adsorption capacity of the new mixed adsorbent was significantly lower than these materials. The water adsorption data on the mixed adsorbent could be correlated according to Polyani's potential theory 相似文献
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以静电纺丝制备的壳聚糖(CS)/聚乙烯醇(PVA)纳米纤维膜为吸附剂,研究了反应时间、甲基橙初始质量浓度、膜吸附剂用量和pH值对吸附甲基橙染料的影响,并通过吸附动力学行为和吸附等温线研究了其吸附机制。结果表明:当pH值在5~9之间、甲基橙初始质量浓度为100 mg/L、吸附剂用量为30 mg、反应时间为60~120 min之间时,吸附效果最佳且吸附平衡时间为3 h;CS/PVA膜对甲基橙的吸附既有物理吸附也有化学吸附,化学吸附占主导作用,CS/PVA膜对甲基橙的吸附符合Langmuir等温线和拟二级动力学模型。 相似文献