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基于Aspen Adsorption模拟软件解析二塔六步变压吸附工艺 认领
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作者 李常艳 刘鹰 张晓红 《当代化工研究》 2021年第3期114-116,共3页
变压吸附作为一种新型的气体分离技术,在煤化工气体净化过程中受到化工技术人员的广泛关注。《化学工艺学》教材中针对变压吸附技术只做了简单的文字说明,没有分析其工艺流程。本文利用Aspen Adsorption模拟软件,以二塔六步式吸附工艺... 变压吸附作为一种新型的气体分离技术,在煤化工气体净化过程中受到化工技术人员的广泛关注。《化学工艺学》教材中针对变压吸附技术只做了简单的文字说明,没有分析其工艺流程。本文利用Aspen Adsorption模拟软件,以二塔六步式吸附工艺流程为例,对变压吸附工艺过程进行解析,以便学生深入了解变压吸附工艺的基本原理和过程。 展开更多
关键词 变压吸附 Aspen Adsorption 二塔六步式
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Hydrous cerium oxides coated glass fiber for efficient and long-lasting arsenic removal from drinking water 认领
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作者 Ronghui Li Weiyi Yang +2 位作者 Shuang Gao Jianku Shang Qi Li 《先进陶瓷:英文版》 SCIE CAS CSCD 2021年第2期247-257,共11页
A novel arsenic adsorbent with hydrous cerium oxides coated on glass fiber cloth(HCO/GFC)was synthesized.The HCO/GFC adsorbents were rolled into a cartridge for arsenic removal test.Due to the large pores between the ... A novel arsenic adsorbent with hydrous cerium oxides coated on glass fiber cloth(HCO/GFC)was synthesized.The HCO/GFC adsorbents were rolled into a cartridge for arsenic removal test.Due to the large pores between the glass fibers,the arsenic polluted water can flow through easily.The arsenic removal performance was evaluated by testing the equilibrium adsorption isotherm,adsorption kinetics,and packed-bed operation.The pH effects on arsenic removal were conducted.The test results show that HCO/GFC filter has high As(Ⅴ)and As(Ⅲ)removal capacity even at low equilibrium concentration.The more toxic As(Ⅲ)in water can be easily removed within a wide range of solution p H without pre-treatment.Arsenic contaminated ground-water from Yangzong Lake(China)was used in the column test.At typical breakthrough conditions(the empty bed contact time,EBCT=2 min),arsenic researched breakthrough at over 24,000 bed volumes(World Health Organization(WHO)suggested that the maximum contaminant level(MCL)for arsenic in drinking water is 10 mg/L).The Ce content in the treated water was lower than 5 ppb during the column test,which showed that cerium did not leach from the HCO/GFC material into the treated water.The relationship between dosage of adsorbents and the adsorption kinetic model was also clarified,which suggested that the pseudo second order model could fit the kinetic experimental data better when the adsorbent loading was relatively low,and the pseudo first order model could fit the kinetic experimental data better when the adsorbent loading amount was relatively high. 展开更多
关键词 hydrous cerium oxide(HCO) glass fiber cloth(GFC) column test adsorption kinetics adsorption mechanism
SO2在成型活性炭表面吸附脱附性能实验研究 认领
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作者 何佳豪 崔梦祺 +4 位作者 季雷 於克良 刘妍 刘少俊 宋印东 《江苏科技大学学报:自然科学版》 CAS 2021年第1期51-57,共7页
工业上通常采用成型活性炭用于SO2的脱除及硫资源回收,在这一过程中SO2的吸附脱附特性对于系统运行具有重要的影响.文中采用适于工业应用的大颗粒活性炭,研究了SO2在其表面的吸附脱附性能.研究结果表明:活性炭的吸附特性受烟... 工业上通常采用成型活性炭用于SO2的脱除及硫资源回收,在这一过程中SO2的吸附脱附特性对于系统运行具有重要的影响.文中采用适于工业应用的大颗粒活性炭,研究了SO2在其表面的吸附脱附性能.研究结果表明:活性炭的吸附特性受烟气组分、空速及再生的影响,在O2和H 2O存在条件下,低空速有利于SO2的吸附,而SO2的浓度则对活性炭的吸附存在负面影响;在经历第一次再生循环后,活性炭的SO2吸附量显著减少,但随后的两个循环吸附量无明显损失,表明活性炭理化性质趋于稳定.基于实验结果,分别采用Elocivh、Bangham和LDF模型对活性炭吸附过程进行了拟合,结果显示3种模型都具有较高的相关性,其中Elocivh模型能拟合出活性炭的吸附速率,Bangham和LDF模型用于预测活性炭的平衡吸附量. 展开更多
关键词 活性炭 吸附 烟气脱硫 吸附动力学模型
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CS/PVA微球的制备及其对重金属离子吸附研究 认领
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作者 郑学成 颜玉如 +1 位作者 罗维 唐嘉 《安全与环境工程》 CAS CSCD 北大核心 2021年第2期196-203,共8页
利用聚乙烯醇和戊二醛通过化学交联对壳聚糖进行改性,制备了壳聚糖/聚乙烯醇(CS/PVA)微球,采用傅里叶变换红外光谱、X射线衍射和扫描电镜对CS/PVA微球进行了表征,考察了pH值、吸附时间和重金属离子(Cu2+、Fe3+、Pb2+、Cd2+... 利用聚乙烯醇和戊二醛通过化学交联对壳聚糖进行改性,制备了壳聚糖/聚乙烯醇(CS/PVA)微球,采用傅里叶变换红外光谱、X射线衍射和扫描电镜对CS/PVA微球进行了表征,考察了pH值、吸附时间和重金属离子(Cu2+、Fe3+、Pb2+、Cd2+)溶液初始浓度对CS/PVA微粒吸附性能的影响,并进行了吸附动力学研究。结果表明:CS/PVA微球吸附溶液中重金属离子的最佳pH值为7;准二级动力学模型较好地拟合了4种重金属离子的吸附试验数据,表明其吸附过程以化学反应为主,其中金属螯合作用占主导作用;利用Langmuir等温线模型拟合得到的CS/PVA微球对溶液中Cu2+和Cd2+的最大吸附容量分别为52.33 mg/g和57.81 mg/g,CS/PVA微球对溶液中Fe3+、Pb2+的吸附更符合Freundlich等温吸附模型,其对Pb2+的吸附率最大。 展开更多
关键词 CS/PVA微球 重金属离子 吸附 等温吸附模型
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在多孔有机聚合物中构筑广谱性重金属离子吸附活性位 认领
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作者 赵开庆 吴若雨 +2 位作者 罗翌峰 石春红 胡军 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2021年第3期834-842,共9页
以三维刚性结构的三蝶烯为单体,通过简单的Friedel-Crafts烷基化反应制备得到高比表面积的三蝶烯基多孔有机聚合物(TPOP),在TPOP中接枝乙二胺和氯乙酸钠,构建了广谱重金属离子吸附剂(TPOPCH2EDTA).获得的TPOP-CH2EDTA具有微孔/介... 以三维刚性结构的三蝶烯为单体,通过简单的Friedel-Crafts烷基化反应制备得到高比表面积的三蝶烯基多孔有机聚合物(TPOP),在TPOP中接枝乙二胺和氯乙酸钠,构建了广谱重金属离子吸附剂(TPOPCH2EDTA).获得的TPOP-CH2EDTA具有微孔/介孔结构,其微孔尺寸为1.6 nm,BET比表面积为634 m2/g,利于重金属离子传递和配位作用的强化.TPOP-CH2EDTA对重金属离子具有吸附广谱性,其对Ag(Ⅰ),Cu(Ⅱ),Ni(Ⅱ),Zn(Ⅱ),Co(Ⅱ),Sn(Ⅳ),Pb(Ⅱ),Cd(Ⅱ),Fe(Ⅲ)和Cr(Ⅲ)等10种重金属离子的去除率均高于98%.以Pb(Ⅱ)为典型的重金属污染物,通过Langmuir模型计算得到Pb(Ⅱ)的最大吸附容量高达184.5 mg/g;具有拟二级吸附动力学特征,吸附速率快,动力学常数k2为0.0173 g·mg‒1·min‒1;经过5次循环使用后,Pb(Ⅱ)的去除效率仍高达95.8%.TPOPCH2EDTA对混合溶液中Pb(Ⅱ)和Cu(Ⅱ)的去除率均高于99%,且对含有大量无机盐[如Ca(Ⅱ),Mg(Ⅱ),K(Ⅰ)和Na(Ⅰ)离子]和有机化合物的复杂真实水体系,Pb(Ⅱ)和Cu(Ⅱ)的去除效率仍高于90%.因此,通过调控多孔有机聚合物微观结构(如比表面积、孔径和吸附位点密度)而构筑的广谱性重金属吸附材料,为协同去除复杂水系统中混合重金属离子提供了方案. 展开更多
关键词 重金属离子 吸附 多孔有机聚合物 广谱性 吸附性能
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Estimating soil ammonium adsorption using pedotransfer functions in an irrigation district of the North China Plain 认领
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作者 Chunying WANG Defeng WU +3 位作者 Xiaomin MAO Jingming HOU Lei WANG Yuping HAN 《土壤圈:英文版》 SCIE CAS CSCD 2021年第1期157-171,共15页
Extensive use of chemical fertilizers in agriculture can induce high concentration of ammonium nitrogen(NH4+-N) in soil. Desorption and leaching of NH4+-N has led to pollution of natural waters. The adsorp... Extensive use of chemical fertilizers in agriculture can induce high concentration of ammonium nitrogen(NH4+-N) in soil. Desorption and leaching of NH4+-N has led to pollution of natural waters. The adsorption of NH4+-N in soil plays an important role in the fate of the NH4+-N. Understanding the adsorption characteristics of NH4+-N is necessary to ascertain and predict its fate in the soil-water environment, and pedotransfer functions(PTFs) could be a convenient method for quantification of the adsorption parameters. Ammonium nitrogen adsorption capacity, isotherms, and their influencing factors were investigated for various soils in an irrigation district of the North China Plain. Fourteen agricultural soils with three types of texture(silt, silty loam, and sandy loam) were collected from topsoil to perform batch experiments. Silt and silty loam soils had higher NH4+-N adsorption capacity than sandy loam soils.Clay and silt contents significantly affected the adsorption capacity of NH4+-N in the different soils. The adsorption isotherms of NH4+-N in the 14 soils fit well using the Freundlich, Langmuir, and Temkin models. The models’ adsorption parameters were significantly related to soil properties including clay,silt, and organic carbon contents and Fe2+ and Fe3+ ion concentrations in the groundwater. The PTFs that relate soil and groundwater properties to soil NH4+-N adsorption isotherms were derived using multiple regressions where the coefficients were predicted using the Bayesian method. The PTFs of the three adsorption isotherm models were successfully verified and could be useful tools to help predict NH4+-N adsorption at a regional scale in irrigation districts. 展开更多
关键词 adsorption capacity adsorption isotherm ammonium nitrogen groundwater quality soil properties
等级孔MFI分子筛的合成及高效吸附结晶紫性能研究 认领
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作者 姬亚军 李甜甜 +2 位作者 高培林 邓汝涵 殷群伟 《信阳师范学院学报:自然科学版》 CAS 北大核心 2021年第2期277-282,共6页
针对传统ZSM-5分子筛孔径小,阻碍大分子吸附的缺陷.通过水热法合成微介孔复合片状MFI分子筛(MFI),用于吸附水中结晶紫(CV)染料.MFI与ZSM-5具有相同的MFI型分子筛晶体结构.与ZSM-5相比,MFI的比表面积更大、孔容更多、平均孔径更大,有利... 针对传统ZSM-5分子筛孔径小,阻碍大分子吸附的缺陷.通过水热法合成微介孔复合片状MFI分子筛(MFI),用于吸附水中结晶紫(CV)染料.MFI与ZSM-5具有相同的MFI型分子筛晶体结构.与ZSM-5相比,MFI的比表面积更大、孔容更多、平均孔径更大,有利于吸附大分子染料.然后,详细考察了溶液pH、吸附时间、染料浓度以及温度对MFI吸附效果的影响,并与ZSM-5进行对比.结果表明:ZSM-5和MFI吸附CV的最优pH为7.吸附过程在10 min内即可达到平衡,符合准二级动力学模型和Langmuir等温模型.MFI的最大吸附量为195.97 mg/g,是ZSM-5的3.58倍,主要归因于MFI优异的等级孔结构特性. 展开更多
关键词 ZSM-5分子筛 等级孔分子筛 吸附 结晶紫 吸附量
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Activated Carbon Based on Acacia Wood (<i>Auriculeaformis</i>, Côte d’Ivoire) and Application to the Environment through the Elimination of Pb<sup>2+</sup>Ions in Industrial Effluents 认领
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作者 Drissa Ouattara Kra Grah Patrick Atheba +2 位作者 N’da Arsène Kouadio Patrick Drogui Albert Trokourey 《封装与吸附期刊(英文)》 2021年第1期18-43,共26页
The objective of this study is to develop carbon, that of <i></span><i><span style="font-family:Verdana;">Acacia auriculeaformis</span></i><span style="font-family... The objective of this study is to develop carbon, that of <i></span><i><span style="font-family:Verdana;">Acacia auriculeaformis</span></i><span style="font-family:Verdana;"></i></span><span style="font-family:Verdana;"> through its activation in order to eliminate lead in an aqueous medium. A series of activated carbon has been prepared by chemical activation with phosphoric acid, sodium hydroxide and sodium chloride. The determi</span><span style="font-family:Verdana;">nation of the physico-chemical properties of the prepared carbon guided the choice of phosphoric acid activated carbon as the best adsorbent for the</span><span style="font-family:Verdana;"> elimination of lead(II) in </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">an </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">aqueous solution. Pb</span><sup><span style="font-family:Verdana;">2+</span></sup><span style="font-family:Verdana;"> adsorption tests in batch mode have shown that the adsorption capacity is influenced by various parameters such as mass, pH, concentration of Pb<sup>2+</sup> ions and contact time linked to the medium and the adsorbent. Adsorption isotherms, kinetic models and thermodynamics have been used to describe the adsorption process. The equilibrium data for activated charcoal correspond well to the model of Freundlich, </span><span style="font-family:Verdana;">Langmuir, Temkin and Kiselev. The kinetic adsorption data proved to be </span><span style="font-family:Verdana;">better described by the pseudo-second order model with </span><span style="font-family:Verdana;">external and intraparticle diffusion which are two decisive steps in the</span><span style="font-family:Verdana;"> adsorption process of Pb<sup>2+</sup> ions. Thermodynamics and adsorption isotherms predict a spontaneous exothermic surface reaction, of the chemisorption type, with ion </span><span><span style="font-family:Verdana;">retention 展开更多
关键词 Acacia auriculeaformis Activated Carbon Lead(II) Ion Adsorption Isotherms Kinetics
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海藻酸钠基吸附材料去除水中重金属离子的研究进展 认领
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作者 郭成 高翔鹏 +3 位作者 李明阳 郝军杰 龙红明 赵卓 《过程工程学报》 CAS CSCD 北大核心 2021年第1期3-17,共15页
重金属污染是当今工业发展所面临的一个重要环境问题之一,由于吸附法具有原材料来源广泛、价格低廉、可循环利用等特征,被认为是一种绿色环保的重金属离子去除方法。海藻酸钠是一种天然多糖,其表面存在大量对重金属离子吸附能力优良的... 重金属污染是当今工业发展所面临的一个重要环境问题之一,由于吸附法具有原材料来源广泛、价格低廉、可循环利用等特征,被认为是一种绿色环保的重金属离子去除方法。海藻酸钠是一种天然多糖,其表面存在大量对重金属离子吸附能力优良的羟基和羧基,目前已被广大科研人员用于实验室吸附材料的制备及研究。通过表面嫁接、交联等改性手段制备的海藻酸钠基吸附材料对重金属离子吸附容量大、去除彻底,拥有较好的工业应用前景。但由于海藻酸钠分子稳定性低、耐热性较差,目前在工业中尚无大规模应用。本工作综述了海藻酸钠基吸附材料的发展现状,介绍了海藻酸钠的结构特点和理化性质,分析了物理、化学改性的海藻酸钠去除重金属离子的吸附特性和影响因素,总结了这些材料对于重金属离子的吸附机理并指出当前研究在工业应用方面尚存的不足之处。在后续研究中,若能有效结合材料科学与环境科学的优势,制备出结构稳定、吸附性能优良的海藻酸钠基吸附材料,对于提升海藻酸钠及其他天然生物质材料的工业价值有重要意义。要点:(1)分析了海藻酸钠基吸附材料去除重金属离子的吸附特性和影响因素。(2)介绍了接枝、交联、复合对海藻酸钠进行改性的方法。(3)分析和总结了海藻酸钠基吸附材料对重金属离子的吸附机理。(4)指出了目前海藻酸钠基材料的应用局限性,提出了潜在的发展方向。 展开更多
关键词 海藻酸钠 吸附 吸附机理 重金属离子 改性
Adsorption of Phosphate and Nitrate Using Modified Spent Coffee Ground and Its Application as an Alternative Nutrient Source for Plant Growth 认领
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作者 Aisyah Humayro Hiroyuki Harada Kanako Naito 《农业化学和环境(英文)》 2021年第1期80-90,共11页
Phosphate (PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup><span style="font-family:Verdana;">) and Nitrate (NO<sub>3</sub><sup style="margin-... Phosphate (PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup><span style="font-family:Verdana;">) and Nitrate (NO<sub>3</sub><sup style="margin-left:-9px;">-</sup></span><span style="font-family:Verdana;">) are two main nutrients that cause wa</span><span style="font-family:Verdana;">ter eutrophication. In the other hand, the presence of PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup></span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">and NO<sub>3</sub><sup style="margin-left:-9px;">-</sup></span><span style="font-family:Verdana;"> is </span><span style="font-family:Verdana;">needed for plant growth. The aims of this study </span><span style="font-family:Verdana;">are </span><span style="font-family:Verdana;">to recycl</span><span style="font-family:Verdana;">e</span><span style="font-family:Verdana;"> Spent Coffee Ground (SCG) modified with calcium hydroxide for adsorption PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup></span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">and NO<sub>3</sub><sup style="margin-left:-9px;">-</sup></span><span style="font-family:Verdana;">. The optimum adsorption capacity for PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup></span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">and NO<sub>3</sub><sup style="margin-left:-9px;">-</sup></span><span style="font-family:Verdana;"> is 36.74 mg/L and 20.21 mg/L, respectively. The Freundlich isotherm model was suitable for PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup></span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">and NO<sub>3</sub><sup style="margin-left:-9px;">-</sup></span><span style="font-family:Verdana;"> adsorption. The kinetic model for adsorption was linear using Pseudo-second order. The application of modified SCG after enrich</span><span style="font-family:Verdana;">ment with PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup></span><span style="font-family:Verdana; 展开更多
关键词 Spent Coffee Ground ADSORPTION Calsium Hydroxide Phosphate and Nitrate Plant Growth
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Adsorption of Tartrazine onto Activated Carbon Based Cola Nuts Shells: Equilibrium, Kinetics, and Thermodynamics Studies 认领
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作者 Dantio Nguela Christian Brice Ngomo Horace Manga +5 位作者 Bénédoué Serge Arnold Kouotou Daouda Abega Aimé Victoire Ndongo Ndongo Alain Giresse Che Randy Nangah Ndi Julius Nsami 《无机化学期刊(英文)》 2021年第1期1-19,共19页
The uptake of tartrazine from its aqueous solution by powdered activated carbon prepared from cola nut shells chemically activated with potassium hydroxide (ACK) and phosphoric acid (ACP) has been investigated using k... The uptake of tartrazine from its aqueous solution by powdered activated carbon prepared from cola nut shells chemically activated with potassium hydroxide (ACK) and phosphoric acid (ACP) has been investigated using kinetics models. Batch isotherm data were analysed with the pseudo-first order, pseudo-second order model as well as the intraparticle diffusion model. For structural elucidation, the materials were characterized using FTIR, XRD and SEM. These analyses revealed that the activated carbons (ACK and ACP) were predominantly mesoporous with several oxygen-containing functional groups dispersed on their surface. The reaction was systematically investigated under various experimental conditions such as contact time, adsorbent dose and pH. For the two adsorbents, the quantity adsorbed of 19.256 mg/g and 18.196 mg/g respectively for ACP and ACK at respective contact times of 5 and 10 min were obtained. The adsorption data were tested with the Langmuir, Freundlich models. Langmuir model was found to best describe the adsorption of tartrate ions with maximum monolayer adsorption capacities of 24.57 and 21.59 mg/g for ACP and ACK, respectively. Results analysis indicated clearly that the pseudo-second order kinetic rate model best fitted the experimental data and therefore was the adsorption controlling mechanism for both adsorbents. Thermodynamic studies revealed that the adsorption process was spontaneous and exothermic for ACP with increased randomness at the solid solution interface, then exothermic but non-spontaneous for ACK. The results show that these activated carbons could be an alternative for more costly adsorbents for the purpose of tartrate ions elimination. 展开更多
关键词 Cola Nuts Shells Activated Carbon ADSORPTION TARTRAZINE
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Preparation of Polymer-Mineral Nanocomposites Based on Vinyl Monomers and Dispersed Inorganic Oxides 认领
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作者 Volodymyr Dutka Yaroslav Kovalskyi +1 位作者 Olena Aksimentyeva Nataliya Oshchapovska 《化学工程与科学期刊(英文)》 2021年第1期18-28,共11页
The polymer-mineral composites were synthesized using vinyl monomers styrene<span "="" style="font-size:10.5pt;"><span style="font-size:12px;">, methyl acrylate, and buty... The polymer-mineral composites were synthesized using vinyl monomers styrene<span "="" style="font-size:10.5pt;"><span style="font-size:12px;">, methyl acrylate, and butyl acrylate with nano dispersed oxides Fe</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">3</span></sub><span style="font-size:12px;">, Cr</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">3</span></sub><span style="font-size:12px;">, V</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">5</span></sub><span style="font-size:12px;"> and SiO</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;"> in the presence of benzoyl peroxide and other peroxide initiators. Benzoyl peroxide adsorption on Fe</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">3</span></sub><span style="font-size:12px;">, Cr</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">3</span></sub><span style="font-size:12px;">, and V</span><sub><span style="font-size:12px;">2</span></sub><span style="font-size:12px;">O</span><sub><span style="font-size:12px;">5</span></sub><span style="font-size:12px;"> surfaces was studied. The adsorption parameters were found: adsorption-desorption equilibrium constants, maximum adsorption, and the area occupied by the molecule benzoyl peroxide on the surface of the adsorbent. The molecular weights of the polymers in the composites and the degree of grafting of the macromolecules of the polymer to the surface of oxides were studied. It has been found that the surface of the dispersed oxides influences the rate of thermal decomposition of the peroxide initiators and the polymerization parameters of the vinyl monomers.</span></span> 展开更多
关键词 Polymer-Mineral Composites Organic Peroxides Radical Polymerization Peroxide Thermal Degradation Metal Oxides ADSORPTION Effect of Surface
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Adsorption and Kinetic Study of Activated Carbon Produced from Post-Consumer Low-Density Polyethylene (LDPE) Wastes 认领
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作者 Olajumoke Alabi-Babalola Elizabeth Aransiola Toyin Shittu 《化学工程与科学期刊(英文)》 2021年第1期38-64,共27页
Post-consumer polymeric wastes in form of low-density polyethylene (LDPE) can now be considered suitable as a precursor for the synthesis of low-cost activated carbon (AC). This study produced AC from LDPE using sulph... Post-consumer polymeric wastes in form of low-density polyethylene (LDPE) can now be considered suitable as a precursor for the synthesis of low-cost activated carbon (AC). This study produced AC from LDPE using sulphuric acid (H<sub>2</sub>SO<sub>4</sub>) and potassium hydroxide (KOH) as the activating agent. The reaction conditions for pyrolysis were varied in the range of 0.50 - 2.00 M, 400<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#ffffff;"="">°</span>C - 500<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#ffffff;"="">°</span>C, and 45 - 60 minutes. Physico-chemical investigations reveal that AC yield is significantly dependent on both carbonization temperatures and time. The obtained optimum values of 446.50<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#ffffff;"="">°</span>C and 51.09 mins gave a yield of 24% for the base-activated carbon. The high iodine numbers obtained strongly indicate the presence of large surface area and pore volumes is further confirmed using the Scanning Electron Microscopy (SEM) analysis which reveals the presence of pores on the external surface of the carbons. Fourier Transform Infrared Technique (FTIR) analysis further shows that the synthesized compounds are purely carbon with rich oxy-gen-surface complexes on the surface which is as a result of the introduction of the chemical oxidizing agents. The produced carbons were found to have high adsorption affinity for selected inorganic ions which are: Mn<sup>7+</sup>, Co<sup>2+</sup>, and Cr<sup>6+</sup>. Adsorption isotherm results show the adsorption process to be favourable with the Langmuir isotherm parameter RL having values of <1, while the Freudlich adsorption model was found to perfectly fit the data at selected adsorbent dosages and adsorbate concentrations. The pseu-do-second-order model provides the best correlation for the kinetic analy 展开更多
关键词 Activated Carbon Low-Density Polyethylene Wastes PYROLYSIS Chemical Activation Optimization ADSORPTION
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Analysis of CO<sub>2</sub>Pressure Swing Adsorption Simulation by Considering the Transport Phenomena in the Adsorber 认领
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作者 Takehiro Esaki Hideaki Kuronuma Noriyuki Kobayashi 《材料科学与化学工程(英文)》 2021年第3期39-54,共16页
This study focused on CO<sub>2</sub> separation technology with adsorption. This paper describes the analysis carried out by a CO<sub>2</sub> pressure swing adsorption simulation to scale up th... This study focused on CO<sub>2</sub> separation technology with adsorption. This paper describes the analysis carried out by a CO<sub>2</sub> pressure swing adsorption simulation to scale up the absorber. An unsteady one-dimensional balance model was constructed by considering the material, energy, and momentum. In the CO<sub>2</sub> breakthrough test, the beginning time and CO<sub>2</sub> concentration at outlet of CO<sub>2</sub> breakthrough in the calculation were almost equivalent to that of experiment results. The correlation consistency of the calculation results with the analysis model and the experimental results obtained by a bench scale experiment was evaluated. The transport phenomena in the adsorber were investigated at the adsorption, rinse, and desorption steps according to the calculation results. The starting time of CO<sub>2</sub> breakthrough obtained by the analysis is equal to that obtained by the adsorption breakthrough experiment. This confirms that the CO<sub>2</sub> adsorption, and the temperature and velocity distribution in the adsorber, change as a function of the adsorption, rinse, and desorption steps, respectively. Additionally, the CO<sub>2</sub> concentration of the captured gas and the amount of CO<sub>2</sub> quantity were 93.4% per day and 2.9 ton/day, respectively. These values are equal to those obtained by the bench scale experiment. 展开更多
关键词 Carbon Dioxide Separation Pressure Swing Adsorption Numerical Analysis
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文章速递片状纳米铁氧化物吸附性能的研究 认领
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作者 郑楠 何梦瑶 严静雯 《韶关学院学报》 2021年第3期53-58,共6页
为了减少染料废水对环境的污染,以片状纳米羟基氧化铁(s-FeOOH)为吸附剂,研究其对水中甲基橙染料的吸附性能.采用电子扫描显微镜(SEM)、傅里叶红外光谱(FTIR)、X射线衍射(XRD)、氮气吸附脱附等手段对吸附剂进行了表征.结果表明:片状纳... 为了减少染料废水对环境的污染,以片状纳米羟基氧化铁(s-FeOOH)为吸附剂,研究其对水中甲基橙染料的吸附性能.采用电子扫描显微镜(SEM)、傅里叶红外光谱(FTIR)、X射线衍射(XRD)、氮气吸附脱附等手段对吸附剂进行了表征.结果表明:片状纳米羟基氧化铁可以有效提高甲基橙的吸附量,比块状羟基氧化铁(FeOOH)提高了50.5%.吸附量随甲基橙溶液初始浓度、吸附剂添加量的升高而增大.弱酸性和中性条件对吸附更有利.吸附过程是放热过程,温度对吸附效果的影响不大.吸附等温模型更符合Freundlich模型,吸附过程更符合拟一级动力学方程. 展开更多
关键词 羟基氧化铁 纳米材料 甲基橙 吸附 吸附动力学
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乳酸菌对重金属离子吸附能力的研究进展 认领
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作者 白英 孙悦 王纯玮 《中国乳品工业》 CAS 北大核心 2021年第1期39-45,共7页
重金属是环境污染的主要污染物之一,其特点是在环境中难以分解,并且能够通过食物链进行生物富集。因此,重金属的有效处理是当前面临的首要问题。研究发现,乳酸菌具有吸附重金属的能力。此外,作为食品安全级别的益生菌,乳酸菌可以安全有... 重金属是环境污染的主要污染物之一,其特点是在环境中难以分解,并且能够通过食物链进行生物富集。因此,重金属的有效处理是当前面临的首要问题。研究发现,乳酸菌具有吸附重金属的能力。此外,作为食品安全级别的益生菌,乳酸菌可以安全有效地去除重金属。本文介绍了重金属和乳酸菌的相关知识,重点阐述了乳酸菌作为生物吸附剂的潜力以及对重金属吸附的研究进展,并探究了重金属被吸附的机理以及相关影响因素。以期为今后乳酸菌吸附重金属的研究提供有效的参考。 展开更多
关键词 乳酸菌 重金属 吸附
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活性炭-高岭土混合吸附剂对亚甲基蓝吸附性能研究 认领
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作者 李维鑫 曹向禹 田俊阳 《皮革与化工》 CAS 2021年第1期1-3,25,共4页
以亚甲基蓝为模拟污染物,采用混合吸附剂处理废液,考察投加量、pH值、温度、时间等因素对亚甲基蓝去除率和吸附量的影响。结果表明:活性炭与高岭土的质量比为2∶1,吸附剂投加量为0.2 g/150 mL,温度为35℃,时间为60 min,此时亚甲基蓝的... 以亚甲基蓝为模拟污染物,采用混合吸附剂处理废液,考察投加量、pH值、温度、时间等因素对亚甲基蓝去除率和吸附量的影响。结果表明:活性炭与高岭土的质量比为2∶1,吸附剂投加量为0.2 g/150 mL,温度为35℃,时间为60 min,此时亚甲基蓝的去除率可达95%,pH变化对此吸附行为的影响不大;吸附等温线及动力学研究表明,此吸附满足Freundlich等温线模型,吸附符合准二级动力学模型,为化学吸附。 展开更多
关键词 吸附 亚甲基蓝 活性炭 高岭土
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核桃壳炭的制备及其对氨氮废水的吸附性能研究 认领
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作者 靳珂 陆倩 +2 位作者 马来九 李惠娟 史正军 《生物质化学工程》 CAS 北大核心 2021年第1期63-69,共7页
为解决当前氨氮废水污染问题,以自制核桃壳炭为吸附剂,以NH+4为模型吸附分子,考察了核桃壳预处理方式、焙烧温度、焙烧时间和铵根离子初始浓度等对氨氮废水吸附的影响,并采用多种手段对核桃壳炭进行表征。研究结果表明:经H3PO4预处理后... 为解决当前氨氮废水污染问题,以自制核桃壳炭为吸附剂,以NH+4为模型吸附分子,考察了核桃壳预处理方式、焙烧温度、焙烧时间和铵根离子初始浓度等对氨氮废水吸附的影响,并采用多种手段对核桃壳炭进行表征。研究结果表明:经H3PO4预处理后于700℃焙烧2 h制备的核桃壳炭对低浓度的NH+4具有优异的吸附能力;当铵根离子初始质量浓度为8 mg/L,100 mL NH+4溶液中加入核桃壳炭2 g,吸附时间为240 min时,NH+4去除率达93.41%;核桃壳炭吸附氨氮符合准二级动力学模型。比表面积和孔径分析结果表明:经H3PO4预处理后制备的核桃壳炭的比表面积为269.18 m^2/g,总孔容积为0.1736 cm^3/g,微孔容积为0.125 cm^3/g,平均孔径为5.46 nm。FT-IR、XRD和SEM分析表明:经H3PO4预处理制备的核桃壳炭为石墨碳晶相,表面呈现石墨片层结构,从而使其具有良好的NH+4的吸附性能。 展开更多
关键词 核桃壳炭 氨氮 吸附性 废水
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CH4在PVDF中渗透行为及机理的分子模拟研究 认领
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作者 张学敏 王品 +4 位作者 李厚补 周腾 肖春红 冯金茂 钟明强 《中国塑料》 CAS CSCD 北大核心 2021年第3期97-104,共8页
采用巨正则蒙特卡洛法(GCMC)和分子动力学法(MD)相结合的方法模拟研究了典型气体CH4在聚偏氟乙烯(PVDF)中的吸附扩散行为,探讨了温度及压力对气体吸附扩散能力的影响,分析了CH4在PVDF中的吸附位点及扩散轨迹。模拟结果表明,CH4... 采用巨正则蒙特卡洛法(GCMC)和分子动力学法(MD)相结合的方法模拟研究了典型气体CH4在聚偏氟乙烯(PVDF)中的吸附扩散行为,探讨了温度及压力对气体吸附扩散能力的影响,分析了CH4在PVDF中的吸附位点及扩散轨迹。模拟结果表明,CH4在PVDF中的溶解系数、渗透系数随温度的升高先增大后减小,随压力的升高而增大;扩散系数和自由体积分数均随温度和压力的升高而增大;吸附过程中,CH4在PVDF内呈现有选择性地聚集吸附,且多吸附于模拟晶胞中的低势能区;随后,PVDF内的CH4分子在以空穴形式存在的自由体积之间进行扩散,温度越高、压力越大,扩散能力越强。 展开更多
关键词 聚偏氟乙烯 渗透 吸附 扩散 分子模拟
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常用吸附剂及其回收再生技术研究 认领
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作者 左雨欣 任晓聪 《当代化工研究》 2021年第6期41-42,共2页
吸附法在处理环境污染中具有特殊地位,吸附剂可以有效的吸附各种污染物,在处理有害或难降解的杂质上更能体现其优越性。吸附剂吸附大量污染物后,其吸附位点会逐渐减少直至失去吸附能力,为了吸附剂的循环利用,需要对其进行再生处理。本... 吸附法在处理环境污染中具有特殊地位,吸附剂可以有效的吸附各种污染物,在处理有害或难降解的杂质上更能体现其优越性。吸附剂吸附大量污染物后,其吸附位点会逐渐减少直至失去吸附能力,为了吸附剂的循环利用,需要对其进行再生处理。本文介绍了几种常见的吸附剂,并总结了多种常用的吸附剂回收再生技术,并对这几种技术的优缺点进行了简单的阐述。 展开更多
关键词 吸附剂 再生技术 吸附 环境治理
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