啶虫脒和苯胺双组分在树脂上的竞争吸附行为

[目的]研究水溶液中啶虫脒和苯胺双组分在树脂上的吸附行为、树脂对2组分的吸附选择性。[方法]以啶虫脒/苯胺为吸附质,以D201和ZH202树脂为吸附剂,研究啶虫脒和苯胺在单组分、双组分水溶液中2种树脂上288、303、313 K温度下的吸附行为。[结果]2种吸附剂对单组分2种吸附质的吸附等温线符合Freundlich方程,苯胺和啶虫脒在2种吸附剂上吸附过程均为放热过程。[结论]啶虫脒和苯胺双组分共存吸附体系下,呈现竞争吸附现象。     

D401树脂对铜镍废水的吸附特性

研究了D401树脂对铜和镍单组分及双组分的吸附行为。单组分实验结果表明,初始质量浓度为100mg/L时,D401树脂对铜、镍的吸附量分别是57.22mg/g、74.20mg/g。双组分实验结果表明,初始质量浓度均为100mg/L时,溶液中铜离子的存在使得D401树脂对镍的吸附量降低至26.75mg/g。从铜、镍离子的杂化方式及配合物的稳定常数两方面对双组分吸附行为进行了研究,为废水中铜、镍的分离提供理论依据。     

三辛胺萃取分离乳酸-醋酸

选择三辛胺为络合剂、正辛醇为稀释剂、乳酸和醋酸为被萃溶质 ,系统地研究了水相pH值及络合剂含量对单组分乳酸、醋酸及其混合物萃取特性的影响。在适当假设条件的基础上 ,建立了考虑络合萃取及物理萃取的单组分及双组分体系的相平衡分配系数表达式。在本文的实验条件下 ,随络合剂含量的升高 ,乳酸、醋酸的单组分及其混合物中各组分相平衡分配系数皆升高 ,分离因子 β增大 ;随水相平衡pH值的升高 ,相平衡分配系数均降低 ,分离因子也呈下降的趋势 .采用本文的模型进行模型参数拟合 ,其精度较好。利用单组分的络合反应平衡常数可成功地预测双组分体系中各组分的相平衡分配系数值     

噻吩、苯并噻吩二元组分在Cu（I）-13X上的吸附平衡

测E30和50℃下噻吩、苯并噻吩单组分及双组分在Cu（I）-13X上的吸附等温线．采用Langmuir模型对单组分平衡数据进行关联;采用修正的Langmuir模型对噻吩苯并噻吩二组分吸附平衡进行关联．结果表明：苯并噻吩在与噻吩的竞争吸附中占据优势,30℃时噻吩和苯并噻吩吸附平衡量的计算值与实验值的误差分别为3．6％和2．4％;N50℃时噻吩和苯并噻吩吸附平衡量的计算值与实验值误差分别为3．5％和2．2％;Langmuir模型在不同温度下对二元组分具有一定适用性．     

浸渍顺序对Mo-Ni加氢催化剂结构和性质的影响

以γ-Al2O3为载体,制备Mo、Ni单组分及双组分催化剂,考察浸渍顺序对催化剂结构的影响.通过氮物理吸附、TPR、和XPS等技术进行表征,结果表明,共浸渍法制备催化剂,有利于活性金属组分的还原,并能提高活性金属组分的分散度,同时使催化剂表面具有较高的Ni/Mo原子比.     

丙烯腈和丙烯酸甲酯在活性炭上的吸附平衡

研究了丙烯腈和丙烯酸甲酯在活性炭上的单组分和双组分吸附平衡。实验结果表明,丙烯腈和丙烯酸甲酯的纯组分吸附等温线为典型的Langmuir型。对双组分吸附平衡,用扩展的Langmuir(E-L)方程和理想吸附溶液理论(IAST)进行预测,并与实验结果进行比较。结果表明两种模型对总吸附量的预测都相当准确,但对丙烯腈吸附量的预测,E-L方程计算的平均相对误差达55．9％,而IAST只有9．4％;对丙烯酸甲酯吸附量的预测,E-L方程计算的平均误差为7．7％,IAST只有1．6％。IAST大大提高了预测精度。     

聚乙烯醇缩丁醛包膜活性炭对模拟血液的吸附

利用聚乙烯醇缩丁醛(PVB)对球形活性炭进行包覆,并分析PVB溶液质量分数及其分子量对肌酐、VB12和溶菌酶所构成的血液模拟体系吸附性能的影响。利用吸附动力学与吸附等温线对单组分及相对差异性双组分吸附过程进行分析。采用SEM、BET、压汞法孔隙率测定及FTIR对包覆活性炭形貌、结构进行表征。结果表明:包膜前后活性炭的吸附机理均为化学吸附,PVB质量分数对吸附量及吸附速率的影响最大,且随PVB质量分数的增大而显著下降;PVB分子量的改变则影响较小,但对增强炭表面亲水作用意义重大。双组分体系下,溶菌酶对VB12的竞争吸附作用明显,VB12的竞争吸附强度高达30%以上;肌酐与溶菌酶体系中,两者竞争吸附强度均低于8%,竞争吸附现象不明显。     

聚乙烯醇缩丁醛包膜球形活性炭对血液模拟体系的吸附

利用聚乙烯醇缩丁醛（PVB）对球形活性炭进行包覆并分析PVB溶液质量分数及其分子量，对肌酐、VB12和溶菌酶所构成的血液模拟体系吸附性能的影响。利用吸附动力学与吸附等温线对单组分及相对差异性双组分吸附过程进行分析。采用SEM、BET、压汞法孔隙率测定及FTIR对包覆活性炭形貌、结构进行表征。结果表明：包膜前后活性炭的吸附机理均为化学吸附，PVB质量分数对吸附量及吸附速率的影响最大，且随质量分数的增大而下降显著；PVB分子量则影响较小，但对增强炭表面亲水作用意义重大。双组分体系下：溶菌酶对VB12的竞争吸附作用明显，VB12的竞争吸附强度高达30%以上；肌酐与溶菌酶体系中，两者竞争吸附强度均低于8%，竞争吸附现象不明显。     

数据与物理信息混合驱动的固定床吸附穿透深度学习模型

提出一种基于数据与物理信息混合驱动的固定床吸附穿透深度学习模型(PINN＿MOD)，采用基于残差自适应网格加密策略联合惩罚因子增强外部数据约束方法，通过最小化损失函数逐步调整神经网络参数逼近固定床双组分气体动态吸附过程偏微分方程(PDE)的解。嵌入物理信息神经网络(PINN)模型可以高保真地求解一维单组分对流-扩散模型和一维单组分固定床吸附模型PDE的正向解和逆向解，但在求解长时间尺度一维双组分固定床吸附模型PDE时存在收敛困难。利用传统有限差分方法(FDM)首先计算一维双组分固定床吸附穿透PDE问题，然后将FDM模拟获得的时空区域内组分浓度数据作为外部约束，联合PINN模型一起求解一维双组分固定床吸附穿透PDE。以填充CALF-20和UTSA-16两种MOF材料的固定床吸附CO₂/N₂(摩尔比30∶70)混合物为例，采用PINN＿MOD模型计算出组分CO₂固定床出口穿透曲线，能够较好地复制FDM计算结果，证实了该模型仅依赖于少量外部数据就能有效地获得PDE高保真解。PINN＿MOD模型有望在开发面向气体分离应用的新型金...     

苯对二苯并噻吩在Cu(Ⅰ)-13X上吸附性能的影响

测定了30℃和50℃下,二苯并噻吩的吸附等温线.结果表明,在二苯并噻吩的质量分教为12 00μg/g时二苯并噻吩的平衡吸附量分别为81.1 mg/g和76.8 mg/g,采用Iangmuir模型进行关联,计算值与实验值的误差分别为7.55%和2.57%;实验还考察了苯对二苯并噻吩吸附的影响,发现二苯并噻吩双组分吸附平衡量比单组分分别降低了10.2%和12.1%.固定床穿透实验结果表明:苯存在情况下,二苯并噻吩的穿透容量较单组分降低了24.4%.     

Synthesis of MTBE in zeolite membrane reactors

A zeolite membrane was employed to selectively remove water from the reaction atmosphere during the gas-phase synthesis of methyl-tert-butyl ether (MTBE) from tert-butanol and methanol. This reaction was carried out over a bed of Amberlyst™ 15 catalyst packed on the inside of a zeolite tubular membrane. The results obtained with different hydrophilic membranes (mordenite or NaA zeolite) are presented. Prior to reaction, the zeolite membranes were characterized by measuring their performance in the separation of the equilibrium mixture containing water, methanol, tert-butanol, MTBE and isobutene. The results obtained with zeolite membrane reactors (ZMR) were compared with those of a fixed bed reactor (FBR) under the same operating conditions. MTBE yields obtained with the ZMR at 334 K reached 67.6%, under conditions where the equilibrium value without product removal (FBR) would be 60.9%.     

Synthesis of NaA zeolite from kaolin source

In this work, zeolite NaA was successfully synthesized by a hydrothermal method using kaolin as a combined source for silica and alumina. Zeolite NaA with high static water adsorption was synthesized from the low-cost raw material, kaolin, and the reaction parameters were optimized. Metakaolin was obtained by calcining kaolin at temperatures ranged from 953 K to 1173 K. The synthesis mixture was pre-crystallized at 343 K and crystallized at 373 K successively. Zeolite NaA was obtained, which was confirmed by SEM, XRD and the water adsorption analysis. The optimized metakaolinization temperature was found at 973 K. The influence of Na₂O/SiO₂ molar ratio, pre-crystallization time and seed on the crystallization of NaA zeolite was investigated. A thorough mixing of metakaolin and NaOH solution was favourable for the nucleation/crystallization rate. The obtained NaA zeolite under the optimized conditions shows excellent crystallinity and static water adsorption of 28.0 wt-%, which was higher than 25.9 wt-% of the commercial NaA zeolite. Kaolin was suggested to be a feasible and economical raw material for the practical industrial applications for NaA zeolite.     

PEA-NaA /α-Al2OPEA-NaA /α-Al2O3复合支撑分子筛膜的微波水热合成

采用微波水热合成法在聚醚酰亚胺(PEI)-NaA分子筛/α-Al2O3复合载体表面合成了具有高选择性的致密NaA型分子筛膜,重点考察了微波辐射时间对成膜的影响。采用X射线衍射图谱(XRD)和扫描电子显微镜(SEM)对NaA型分子筛膜进行了表征。XRD结果表明,复合载体表面生成的膜中只有NaA分子筛的晶相;SEM结果表明,复合载体基膜表面覆盖了一层致密连续的NaA型分子筛膜。合成的NaA型分子筛膜在不同质量分数乙醇中的渗透汽化性能结果表明,渗透通量随乙醇质量分数增大而减小,分离因子则反之,当乙醇质量分数为95%时,渗透通量仅0.05 kg/(m2.h),而分离因子高达13 000。     

Silane‐modified NaA zeolite/PAAS hybrid pervaporation membranes for the dehydration of ethanol

To improve the pervaporation selectivity of poly(acrylic acid) sodium (PAAS) membranes incorporated with NaA zeolite, the interface compatibility between zeolite nanocrystals and the polymer matrix was improved by modifying NaA zeolite using 3‐aminopropyltriethoxysilane (APTES). Both X‐ray photoelectron spectra and FTIR confirmed the chemical modification, while the results of zeolite particle size analysis and scanning electron microscopy revealed the improved dispersion of the modified zeolite. Transmission electron microscopy images of these hybrid membranes indicated that the interface between the polymer and modified zeolite phases had improved. The effects of loaded NaA zeolite on the pervaporation performance of hybrid membranes were investigated. The selectivity of hybrid membranes made from APTES‐modified zeolite was higher than that using the original zeolite under the same conditions, because fewer voids resulted from the incompatibility between the zeolite and PAAS and the structure was more homogenous. Based on the Arrhenius plots, the activation energies of water and the ethanol ratio were lower for modified zeolite hybrid membranes, because water molecules experienced less restrictive passage through the membranes compared with the original zeolite‐based hybrid membrane. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Prediction of adsorption and separation of water–alcohol mixtures with zeolite NaA

A new effective pair potential was parameterized for the prediction of the adsorption of mixtures of water and methanol or ethanol in zeolite NaA. The pressure dependence of the adsorption properties such as equilibrium amount of adsorption and isosteric heat of adsorption were calculated at 378 K by molecular simulations. Significantly higher adsorption selectivities were found for water in a wide range of pressure as compared with previous simulation results. The verification of the new model was made by calculating also some structural characteristics of the system.     

Scale-up of NaA zeolite membranes onα-Al2O3 hollow fibers by a secondary growth method with vacuum seeding

NaA zeolite membranes were prepared by secondary growth method on the outer surface ofα-Al2O3 hollow fiber supports. Vacuum seeding method was used for planting zeolite seeds on the support surfaces. Hydrother-mal crystallization was then carried out in a synthesis solution with molar ratio of Al2O3:SiO2:Na2O:H2O=1:2:2:120 at 100 °C for 4 h. Effects of seeding conditions on preparation of hollow fiber NaA zeolite membranes were extensively investigated. Moreover, hollow fiber membrane modules with packing membrane areas of ca. 0.1 and 0.2 m2 were fabricated to separate ethanol/water mixture. It is found that the thickness of seed layer is obviously affected by seed suspension concentration, coating time and vacuum degree. Close-packing seed layer is required to obtain high-quality membranes. The optimized seeding conditions (seed suspension mass concentration of 0.5%–0.7%, coating time of 5 s and vacuum degree of 10 kPa) lead to dense NaA zeolite layer with a thickness of 6–8μm. Typically, an as-synthesized hollow fiber NaA zeolite membrane exhibits good pervaporation performance with a permeation flux of 7.02 kg·m?2·h?1 and separation factor N 10000 for sepa-ration of 90%(by mass) ethanol/water mixture at 75 °C. High reproducibility has been achieved for batch-scale production of hollow fiber NaA zeolite membranes by the hydrothermal synthesis approach.     

管式支撑体内表面NaA分子筛膜的合成与表征

采用转动合成方式通过二次生长法在管式α-Al₂O₃支撑体内表面合成了NaA分子筛膜,采用X射线衍射仪（XRD）、场发射扫描式电子显微镜（FE-SEM）和渗透汽化分离技术对所合成的膜进行了系统表征。考察了合成釜转速对分子筛膜合成的影响,结果表明合成釜转速的提高有利于分子筛膜合成。在转速为4 r·min^-1时所合成NaA分子筛膜分离因子高达2370,渗透通量1.86 kg·h^-1·m^-2左右（乙醇/相似文献   

微波合成的NaA型分子筛膜在乙醇脱水中试及3万吨/年工业示范装置的蒸汽渗透性能研究

设计并搭建了分子筛膜脱水中试装置,对本课题组微波加热技术合成的工业级NaA型分子筛膜进行乙醇/水体系蒸汽渗透的性能研究,得到了NaA型分子筛膜的水渗透通量方程,水透量与原料液含水量、雷诺数之间的关系及变化规律。对精馏与膜分离耦合工艺进行流程模拟,提出了精馏与膜分离的最佳耦合点,并且给出了分子筛膜的价格和寿命对总费用的影响,为NaA型分子筛膜工业应用提供重要参考依据。根据中试结果,在江苏索普集团醋酸加氢制乙醇项目中建设完成了3万吨/年的分子筛膜乙醇脱水装置,是目前国内单套最大的分子筛膜脱水装置。目前,装置已连续运行超过1000h,运行结果良好。     

载银/铜NaA分子筛的制备及抗菌性能研究

探讨了液相离子交换法制备载银/铜NaA分子筛抗菌剂的实验条件,并对载银/铜NaA分子筛样品中载银、铜的含量,抗变色性能及对大肠杆菌、金黄葡萄球菌的抗菌性进行检测。结果表明,与单独载银的NaA分子筛相比,载银/铜NaA分子筛中银和铜含量分别达到5.5%和1.6%,色差更小,抗菌性显著提高。     

SEM–EDX and XRD characterization of zeolite NaA, synthesized from rice husk and aluminium scrap by different procedures for preparation of the initial hydrogel

A number of investigations have demonstrated that zeolite NaA could be synthesized using Si, extracted from rice husk ash; however, experiments on direct extraction of Si from rice husk (RH) are scarce. The main objective of the present study was to explore the possibility to synthesize high-quality zeolite NaA from RH and waste aluminium cans (as a source of Al), applying different procedures for the preparation of initial hydrogel and a unified procedure for crystallization of zeolite NaA. Products were characterized by SEM–EDX and XRD analyses. The investigation demonstrated that Si could be extracted directly from RH, avoiding the process of RH burning. Practically complete dissolution of Si from RH was achieved by alkali treatment (with 10 % NaOH for 7 h) at boiling temperature and atmospheric pressure, i.e. using refluxing system instead of autoclave for the preparation of Si-gel. Zeolite NaA samples synthesized from such Si-gels were pure, highly crystalline and white. Furthermore, it was found that the direct dissolution of Al in Si-gel did not affect the quality of the final product. Although this investigation was not focused on the mechanism of zeolite NaA crystallization, the results obtained indicated clearly that the history of Si-gel preparation played an important role in the nucleation and growth of zeolite NaA crystals and influenced their yield, size, and shape. Therefore, the optimization of Si-gel preparation procedure has to be considered as essential not only for the economy of the synthesis of NaA from RH, but also for the quality of the final product.