2,4-二羟基苯甲酸在3种树脂上的吸附特性

通过静态和动态吸附实验, 研究了717(凝胶型,强碱)、D201(大孔型,强碱)和D301R(大孔型,弱碱)3种阴离子交换树脂对水溶液中2,4-二羟基苯甲酸的吸附特性. 结果表明,717和D201在pH 4~11时、D301R在pH 3~9时吸附能力最好. 在pH=5及温度293~313 K、初始浓度0.6488~6.488 mmol/L条件下,D301R, 717和D201对2,4-二羟基苯甲酸的等温吸附规律均符合Freundlich模型,最大平衡吸附量分别为2.98, 2.66和2.54 mmol/g(吸附未达饱和),均为物理性自发吸附的放热过程. 动力学实验数据用准一级模型方程拟合比准二级更接近实验值. 5%(w) NaCl+2%(w) NaOH脱附液100 mL均可有效洗脱3种树脂上吸附的2,4-二羟基苯甲酸,脱附率达99%. 相同条件下,D301R树脂对2,4-二羟基苯甲酸的吸附性能优于D201和717树脂.     

热解活化法制备高吸附性能椰壳活性炭

以椰壳为原料,采用高温直接热解活化法制备高吸附性能活性炭。研究了活化温度、活化时间对活性炭吸附性能的影响。研究结果表明,活化温度为 900 ℃,热解活化时间为 8 h,升温速率为 10 ℃/min,制得碘吸附值为 1 628.54 mg/g,亚甲基蓝吸附值为 375 mg/g 的高吸附性能椰壳活性炭,得率为 9.41 %。氮气吸附实验结果表明,该活性炭比表面积 1 723 m²/g、总孔容积 0.87 cm³/g、微孔容积 0.68 cm³/g、中孔容积0.18 cm³/g、平均孔径 2.03 nm。热解活化制备的椰壳活性炭样品性能优于市售水蒸气法椰壳净水活性炭国家标准。     

天然气吸附存储用高比表面积活性炭研究进展

综述了物理法、化学法和化学-物理法制备高比表面积活性炭的研究进展,归纳了多粒径混装、粘结剂压制和无粘结剂压制成型3种降低空间体积,提高活性炭颗粒密度的成型方法,介绍了成型活性炭在天然气吸附存储中国内外研究进展,讨论了天然气吸附剂存在的问题、不足以及相应的解决方法。     

水源水质受DEHP污染的粉末活性炭吸附处理工艺

采用含邻苯二甲酸二(2-乙基己基)酯(DEHP)的试验水样模拟城市取水水源发生DEHP水污染事故,测定粉末活性炭(PAC)对水样中DEHP的吸附性能,考察PAC炭种、吸附时间、DEHP初始浓度和PAC投加量等因素对DEHP的吸附量和脱除率的影响。试验结果表明:木屑PAC具有较大的比表面积,对DEHP具有良好的吸附效果,适用于DEHP水污染的应急处理。应急处理一般的DEHP水污染事故,DEHP污染浓度超标10～30倍时,PAC吸附DEHP的最佳条件为:吸附时间120 min,PAC投加量为20～80 mg/L,PAC对DEHP的吸附过程符合Henry等温式。     

载锌NaY分子筛对FCC汽油吸附脱硫性能的影响

采用液相离子交换法将锌离子负载到NaY分子筛上,得到ZnY分子筛脱硫吸附剂。考察了锌离子负载浓度和不同焙烧温度对ZnY分子筛吸附脱硫性能的影响。研究脱硫实验中吸附温度和吸附空速对FCC汽油脱硫性能的影响,样品中的硫含量通过微库仑综合分析仪进行测定。结果表明,Zn(NO₃)₂负载浓度0.30 mol·L^-1、焙烧温度500 ℃、吸附温度30 ℃和吸附空速0.5 h^-1条件下对吸附脱硫性能最有利,脱硫率超过80%。考察两种方法对吸附剂进行再生。     

异丙酚分子印迹聚合物的制备及其结合特性

采用分子印迹技术制备了异丙酚分子印迹聚合物,并考察其结合特性和选择性。以异丙酚为模板分子,甲基丙烯酸为功能单体,二甲基丙烯酸乙二醇酯为交联剂,偶氮二异丁腈为引发剂,甲苯、正己烷为溶剂合成异丙酚分子印迹聚合物。通过平衡吸附实验,研究了异丙酚分子印迹聚合物的结合特性和选择性。Scatchard模型分析表明,在该聚合物中存在对异丙酚有不同亲和力的两类作用位点。此聚合物与异丙酚的结合要优于麝香草酚。此方法可合成异丙酚分子印迹聚合物,通过结合实验和对底物选择性考察,表明该聚合物对异丙酚具有良好的选择性。     

Relation between the adsorbed quantity and the immersion enthalpy in catechol aqueous solutions on activated carbons

An activated carbon, Carbochem(TM)-PS230, was modified by chemical and thermal treatment in flow of H(2), in order to evaluate the influence of the activated carbon chemical characteristics in the adsorption of the catechol. The catechol adsorption in aqueous solution was studied along with the effect of the pH solution in the adsorption process of modified activated carbons and the variation of immersion enthalpy of activated carbons in the aqueous solutions of catechol. The interaction solid-solution is characterized by adsorption isotherms analysis, at 298 K and pH 7, 9 and 11 in order to evaluate the adsorption value above and below that of the catechol pK(a). The adsorption capacity of carbons increases when the solution pH decreases. The retained amount increases slightly in the reduced carbon to maximum adsorption pH and diminishes in the oxidized carbon. Similar conclusions are obtained from the immersion enthalpies, whose values increase with the solute quantity retained. In granular activated carbon (CAG), the immersion enthalpies obtained are between 21.5 and 45.7 J·g(-1) for catechol aqueous solutions in a range of 20 at 1500 mg·L(-1).     

Combining the Physical Adsorption Approach and the Covalent Attachment Method to Prepare a Bifunctional Bioreactor

Aminopropyl-functionalized SBA-15 mesoporous silica was used as a support to adsorb myoglobin. Then, in order to avoid the leakage of adsorbed myoglobin, lysozyme was covalently tethered to the internal and external surface of the mesoporous silica with glutaraldehyde as the coupling agent. The property of amino-functionalized mesoporous silica was characterized by N₂ adsorption-desorption and thermogravimetric (TG) analysis. The feature of the silica-based matrix before and after myoglobin adsorption was identified by fourier transform infrared (FTIR) and UV/VIS measurement. With o-dianisidine and H₂O₂ as the substrate, the peroxidase activity of adsorbed myoglobin was determined. With Micrococus lysodeilicus as the substrate, the antibacterial activity of covalently tethered lysozyme was measured. Results demonstrated that the final product not only presented peroxidase activity of the myoglobin but yielded antibacterial activity of the lysozyme.     

硫酸盐对聚羧酸减水剂吸附量及吸附动力学的影响

在研究聚羧酸减水剂在水泥颗粒表面的吸附量、吸附速率的基础上,运用不同吸附动力学模型对试验结果进行拟合。吸附量测试结果表明:掺0.5%、1.0%Na2SO4会显著降低聚羧酸减水剂在水泥颗粒表面的吸附量,但掺0.1%、0.2%的Na2SO4有利于聚羧酸减水剂的吸附;CaSO4·2H2O对聚羧酸减水剂的吸附量影响不显著。吸附速率测试及拟合结果表明:硫酸盐对聚羧酸减水剂在水泥颗粒表面吸附动力学的影响规律符合Langmuir准二级吸附动力学模型,Na2SO4通过改变聚羧酸减水剂在水泥颗粒表面的准二级吸附速率常数影响聚羧酸减水剂吸附达到平衡的时间,0.2%、1.0%掺量的Na2SO4均延迟了聚羧酸减水剂达到吸附平衡的时间。掺0.2%Na2SO4使准二级吸附速率常数较不掺硫酸盐时有所提高;掺1.0%Na2SO4的准二级吸附速率常数较不掺硫酸盐时大大降低;CaSO4·2H2O对准二级吸附速率常数的影响较Na2SO4要小。     

中性墨水颜料吸附性与分散稳定性研究

中性墨水的流变性和颜料分散稳定性是影响中性墨水品质的两个重要因素,这两个因素又直接受到分散树脂、增稠剂种类与稳态吸附量的影响。本文考查了不同颜基比下增稠剂吸附颜料粒子的量对墨水表观黏度及触变值的影响,并在理想条件下,选择复配碱溶胀型增稠剂对墨水流变性和稳定性进行研究。结果表明,分散树脂与增稠剂对颜料粒子存在动态竞争吸附;当墨水体系中颜基比为3:1,借助0.4% ALCOGUARD 5800与1.0% T-938复合增稠,所制备的中性墨水具有良好的流变性能与分散稳定性。