球形纤维素吸附剂对Cu~(2+)的吸附动力学与热力学研究

以离子液体([Bmim]Cl)为反应介质,丙烯酸为单体,对纤维素进行均相接枝共聚,并采用油包水反相悬浮技术制得球形纤维素吸附剂。采用静态吸附实验方法研究了该吸附剂对水溶液中Cu2+的吸附性能,包括各种因素(溶液pH值,溶液初始浓度,吸附时间,吸附温度)对吸附效果的影响。研究结果表明,适当提高溶液pH值,增加溶液初始浓度,以及延长吸附时间都有利于改善吸附效果;球形纤维素吸附剂对Cu2+的吸附符合Langmuir吸附等温式,吸附过程是自发的放热过程;吸附剂对Cu2+的吸附符合二级吸附动力学模型,吸附过程由膜扩散和颗粒内扩散联合控制。球形纤维素吸附剂对Cu2+的具有很好的吸附性并具有良好的再生性能,可以循环使用。     

多胺类螯合吸附剂对重金属离子吸附分离的研究进展?

综述了多胺类螯合吸附剂制备方法及其对微污染环境、复杂混合环境、高盐环境中重金属离子的特性吸附行为,重点总结了多胺类螯合吸附剂对重金属离子的吸附结合方式、高效分离机制及盐存在下的增强吸附机制,并进一步展望多胺类螯合吸附剂的应用前景、创新设计思路以及理论探索的研究方向,为拓宽多胺类螯合吸附剂在重金属离子无害化处理和资源化回收方面的应用范围,提供了理论和技术指导。     

纤维素基印迹吸附剂的制备及研究性能

以纤维素为原料,1-乙烯基咪唑为最佳功能单体,2,4-二氯苯酚(2,4-DCP)作为模板分子,采用分子印迹技术结合原子转移自由基聚合方法,制备纤维素基印迹吸附材料。利用红外光谱(FT-IR)及扫描电镜(SEM)对材料的结构及性能进行了表征,并对纤维素印迹吸附剂的选择性吸附性能进行研究。     

汽油活性炭基脱硫吸附剂的制备与评价

以250℃温度下浓硫酸改性后的活性炭为载体,采用浸渍法制备了以MnO₂为活性组分的活性炭基的汽油脱硫吸附剂MnO₂/AC,考察了吸附剂的制备条件及脱硫条件对脱硫效果的影响。研究结果表明,适宜的吸附剂制备条件为,以Mn(NO₃)₂为活性组分前驱物,Mn(NO)₂浸渍液浓度0.15mol/L、常温下浸渍24h、焙烧温度350℃、焙烧时间2h。该吸附剂在静态吸附温度120℃、吸附时间2h、剂油质量比0.10的条件下可使原料油硫的质量分数从628.6×10^-6降至221.5×10^-6,脱硫率达到64.8%;在动态吸附温度60℃、空速1.76h^-1的条件下,初始流出汽油硫的质量分数降至21.8×10^-6,初始脱硫率达到96.5%。     

凹凸棒土应用于重金属离子吸附剂的研究

以新型无机矿物材料凹凸棒土作为吸附剂处理废水中的重金属离子。通过扫描电镜、红外光谱及等温吸附-脱附曲线对凹凸棒土进行了表征,并阐述了凹凸棒土对重金属离子的可能吸附机理。在室温下,分别将0.05 g凹凸棒土投入初始质量浓度为500 mg.L-1的Cu(Ⅱ)、Cd(Ⅱ)、Ni(Ⅱ)和Cr(Ⅵ)的溶液中,凹凸棒土对上述离子的平衡吸附量分别高达99、56、117、198 mg.g-1。结果表明,用凹凸棒土吸附废水中的重金属离子切实可行、经济有效。     

天然气吸附剂的开发及其储气性能的研究——Ⅰ-吸附剂制备与体积法评定吸附剂的储气性能

报道了天然气吸附剂的基本制备技术,并采用体积法评定了吸附剂的储气性能。结果表明,采用作者开发的吸附剂制备工艺可获得性能优良的天然气吸附剂。以木质素为原料制备的粉状吸附剂,其比表面积可达２９１２ｍ２／ｇ,微孔体积可达１－４８ｃｍ３／ｇ,平均孔径为１－４８ｎｍ ,堆密度为０－３０ｇ／ｃｍ３ 。在６－０ＭＰａ、２５ ℃下,天然气的吸附储存量可达到１４０Ｖ／Ｖ。天然气吸附剂的储气性能与其比表面、微孔数量、填充密度等参数有重要关系     

负载二氧化锰球形吸附剂的制备及锂吸附性质的研究

将粉末状无机吸附剂MnO_2分散负载于交联聚丙烯酰胺,制成了球形吸附剂。以静态法和柱式法用LiOH(0.1mol/L),LiCl(0.1mol/L)混合溶液和实际盐湖卤水研究了吸附剂对Li~+的吸附性。对LiOH、LiCl等摩尔混合溶液和大柴旦湖水,锂吸附容量分别为5.90和3.40mmol/gMnO_2·HCl溶液(0.25mol/l)可将被吸附的锂近于完全洗脱,同时将吸附剂再生以重新使用。     

变温镁基CO_2吸附剂的制备及应用I.Na/Mg物质的量比

以Mg(NO3)2和Na2CO3为原料,采用正加沉淀法制备镁基CO2吸附剂,利用XRD、SEM-EDS和DTG等方法对吸附剂进行了表征,研究了n(Na)/n(Mg)比对吸附剂的物质组成、形貌和分解温度的影响;在此基础上,通过变温吸附脱附动态循环实验考察了不同吸附剂的CO2吸附性能。实验结果表明,当n(Na)/n(Mg)为8.15时,吸附剂颗粒粒径小、大小均匀、分解温度低,吸附容量达到9.584%(质量分数);经过20次变温吸附脱附循环后,吸附能力仍保持初始吸附量的95.8%,表现出良好的稳定性。     

寡肽吸附剂的制备及吸附机理

为清除尿毒症患者血清中分离出的八肽VVRGCTWW(V8), 制备了不同间隔臂长含苯环的吸附剂Phenc. 吸附实验结果显示, 吸附剂Phe3c具有非常好的吸附能力. 采用NMR和分子模拟技术对吸附剂的模型体系的吸附机理进行了研究. 结果显示, 配体中的苯环可与八肽形成π-π堆积, 而且间隔臂的增长可以克服空间位阻效应, 有效增加配体与V8的作用几率, 进而增强吸附剂与八肽的相互作用. 研究结果表明, 采用合理的分子模型及分子对接方法, 不仅可以合理解释吸附剂的吸附机理, 而且可用于吸附剂的虚拟筛选.     

碳质吸附剂的制备及其对二氯化汞的吸附研究

本文研究了大孔磺化苯乙烯—二乙烯苯共聚珠体在300～900℃的碳化物吸附二氯化汞前后的比表面变化过程,提出最佳吸附条件应选择在剩余比表面变化临界区或者临界区附近。     

Efficient carbon adsorbent for hydrogen sulfide produced from sugar cane bagasse

It was found that a carbon-containing adsorbent produced from sugar cane bagasse and activated by oxidative alkaline treatment has rather high adsorption activity towards H₂S     

Preparation and adsorption properties of PAA-grafted cellulose adsorbent for low-density lipoprotein from human plasma

A new low-density lipoprotein (LDL) adsorbent with good adsorption performance has been obtained by use of a simple preparation procedure. Graft copolymerization of acrylic acid (AA) on to macroporous cellulose beads was performed with cerium ammonium nitrate (CAN) as a redox initiator. The effects of initiator concentration, monomer concentration, and reaction time on grafting were examined. In adsorption tests, several factors affecting adsorption of lipoproteins were investigated in detail. In-vitro study showed that this adsorbent could remove total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), and triglyceride (TG) at levels of 5.55, 4.46, and 2.48 mg g⁻¹, respectively, from human plasma without substantially affecting high-density lipoprotein-cholesterol (HDL-C) and total proteins (TP). The adsorbent prepared in this work might be further studied for potential clinical application.     

低温一步法活性炭基脱硫剂的制备与评价

以木屑为原料,在低温条件下一步法制得活性炭基吸附剂,考察了吸附剂制备条件和液-固、气-固吸附条件对吸附剂脱硫性能的影响。结果表明,吸附剂的最佳制备条件为,浸渍液与木屑质量比为1：1,浸渍液中硝酸质量分率为30%、吸附剂表面NiO负载量为5%,常温下浸渍24 h,400℃焙烧3 h。该吸附剂在0.2 g吸附剂/10 mL模拟油、温度为40℃及时间为5 h的液-固吸附脱硫的条件下,脱硫率为28.36%,吸附四次后饱和吸附硫容量可达2.34 mgS/g;在气-固吸附温度为250℃、空速为6.3 h^-1的条件下,饱和吸附硫容量为2.37 mgS/g;高温气-固吸附脱硫对吸附剂的影响表明,与脱硫前相比,吸附剂在比表面积、总孔体积、微孔体积均有明显提高,这说明气-固吸附脱硫过程同时实现了活性炭的扩孔活化。甲苯溶剂再生实验表明,经五次再生后吸附剂的再生性能均可达90%以上。     

Adsorption of carbon dioxide on microporous carbon adsorbent PAU-10

Carbon dioxide adsorption on the microporous carbon adsorbent PAU-10 within the 177.8—423 K temperature and 0.1—5.13·10⁶ Pa pressure intervals was studied. The isosteres of absolute adsorption are well approximated by straight lines, which do not change their slope on going to temperatures higher than the critical temperature of CO₂. An increase in the differential molar isosteric heat of adsorption (q _st) at 0 < a < 1 mmol g^–1 is explained by the influence of the endothermic effect of adsorption expansion of the adsorbent. In the region of high pressures and nonideal gas phase, q _st is temperature-dependent.     

Influence of mechanical activation on the graft copolymerization of sugarcane bagasse and acrylic acid

Sugarcane bagasse (SCB) was mechanically activated by home-made high efficiency stirring mill. Graft copolymers (SCB-g-PAA) of SCB with different mechanical activation times (t_M) and acrylic acid (AA) have been synthesized by using ammonium persulfate/sodium sulfite redox pair as an initiator in aqueous solution. The effect of t_M on the graft co-polymerization was evaluated by grafting ratio (GR) and grafting efficiency (GE). In addition, scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) were used to characterize the granular morphology, functional groups, crystal structure and thermal properties of the product. It was found that the mechanical activation could split fiber bundles and decrease significantly the crystallinity. SCB degraded after the mechanical activation (MA) and its thermal stability declined. Moreover, the graft copolymerization was enhanced obviously by MA processing. And GR and GE increased with the increase of activation time.     

Adsorption of perfluoropropane on the PAC microporous carbon adsorbent

The adsorption of perfluoropropane (N₃F₈) on the PAC microporous carbon adsorbent, which is close in properties to monoporous adsorbents, was studied at temperatures of 216, 243, 295, 318, and 343 K in the pressure interval from 1 to 1·10⁵ Pa. The adsorption isosters are well approximated by straight lines in the studied interval of temperatures and pressures. The dependence of the isosteric heats of adsorption on filling is described by a curve with a maximum in the region of high fillings. Such a curve is characteristic of adsorbents with a narrow pore size distribution.     

Carbon dioxide adsorption on the microporous ACC carbon adsorbent

Adsorption isotherms of carbon dioxide on the microporous ACC carbon adsorbent and the adsorption deformation of the adsorbent were measured. The heats of adsorption at temperatures raising from 243 to 393 K and pressures from 1 to 5⋅10⁶ Pa were measured. In the low-temperature region (243 K), an increase in the amount adsorbed is accompanied by adsorbent contraction, and at high micropore fillings (a > 10 mmol g⁻¹) the ACC carbon adsorbent expands. At high temperatures, adsorbent expansion is observed in the whole region of micropore filling. At 243 K in the low filling region (a < 1 mmol g⁻¹), the heat of adsorption decreases smoothly from 27 to 24 kJ mol⁻¹. The heat of adsorption remains virtually unchanged in the interval 2 mmol g⁻¹ < a < 11 mmol g⁻¹ and then decreases to 8 kJ mol⁻¹ at a = 12 mmol g⁻¹. Taking into account the nonideal character of the gas phase and adsorbent deformation the heats of adsorption are strongly temperature-dependent in a region of high pressures. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1331–1335, June, 2005.     

功能化程序对笼形聚偕氨肟树脂吸附和吸留性质的影响

聚丙烯颗粒在水溶液中与丙烯腈和二乙烯基苯反应,得接枝交联产物（Ⅰ）。Ⅰ被氨肟化再经成笼反应．得笼形聚偕氨肟树脂（Ⅱ）。笼内仅吸留易于除去的溶剂丙酮。若Ⅰ成笼后再氨肟化,所得吸收剂（Ⅲ）将吸留大量的羟胺,它缓慢地释放出来,干扰吸收剂对酸、碱离子或分子吸附容量的测定。Ⅱ对一些离子例如Hg2+和MnO4-的吸附能力与Ⅲ不同,被认为是两者的网络结构不同所致。     

羧酸在笼形聚偕氨肟树脂上吸咐

碱处理笼形聚偕氨肟树脂（BCAO）对羧酸表现出强的吸附能力。一元羧酸在BCAO树脂上以多层吸附为主要特征。二元和三元羧酸则以单层吸附占优势。后者可能是以双阴离子的一个负极吸着在BCAO树脂表面，形成了对其他羧酸阴离子起排斥作用的负离子场。另外，双阴离子也有可能和两个氨基结合形成次级交联，妨碍着其他离子迁移和扩散。