Elimination of surfactants and small dyes from water with silica-supported dendritic amphiphiles

Silica-supported branched polyethylenimine(Sil@PEI) is a conventional adsorbent and shows a limited affinity to anionic surfactants and small dyes(K = 106?107 L/mol). If the PEI is alkylated with cetyl groups(C16), the K of the resulting adsorbents(Sil@PEI@C16-x, where x is the fraction of PEI units being alkylated) is significantly improved. Optimization shows that Sil@PEI@C16-0.15 can best reduce aqueous surfactants to a residue around 10?10 mol/L; while Sil@PEI@C16-0.6 can reduce even small aqueous dyes to a residue below 10?10 mol/L, nearly 105-fold lower than that by Sil@PEI. The adsorbents are well recyclable. It is believed that in the case of dyes, the dense cetyl shell can isolate the PEI from the bulky water and thus suppress the competitive binding by water; while in the case of surfactants, the semiclosed cetyl shell can simultaneously meet electrostatic complement and hydrophobic complement to the surfactants.     

结晶硅酸盐/硅铝酸盐介孔材料MCM-41的结构特征与应用性能

由于独特的结构特征及表面性质，MCM－41一问世即受到广泛的关注。但由于结构稳定性不足等原因，近年来关于MCM－41的研究骤然降温。本文从“扬长克短”和“扬长避短”的角度出发，对MCM－41作为催化剂、载体材料、吸附材料及在无机－有机复合材料中的潜在应用进行了综述。     

以赖氨酸为配基的内毒素吸附剂的研究

内毒素血症可出现于多种疾病中,如大面积烧伤、重症肝炎、肝硬化等疾病,使机体免疫功能严重受损,引起多器官功能衰竭等一系列严重的病理变化,最终导致不可逆休克和死亡,在美国每年都有超过10万人死于此病,临床上尚无有效的治疗方法,因此,及时、有效地清除或破坏患者体内的内毒素,     

Studies on Thermodynamic Properties of Adsorption of Theophylline by Phenolic Resin Adsorbents

In the present work, the equilibrium adsorption of theophylline was studied by phenolic resin adsor-bents: JDW-2 (made by ourselves) and Duolite S-761 within a temperature range of 303--323 K. The experi-mental results show that the Freundlich adsorption law is applicable to the adsorption of theophylline on thetwo adsorbents, the exponents n＞l indicate that they are favorable to the adsorptions; the negative values ofall the isosteric adsorption enthalpies for the theophylline indicate the exothermic process of the adsorption,while the range(10—40 kJ/mol) of their magnitudes manifests the physisorption process; other thermody-namic properties, the free energy changes and the entropy change associated with adsorption have been calcu-lated from the Gibbs adsorption equation and the Gibbs-Helmholtz equation.     

尿毒症中分子毒物吸附剂的研究(Ⅲ)——酸性氨基酸修饰交联壳聚糖

以球状壳聚糖为载体,酸性氨基酸为配体,合成了尿毒症中分子毒物吸附剂,并测试了其血液相容性.为了研究吸附剂对尿毒症患者体内多肽蓄积物的吸附性能,选取分子量不同的6种多肽作为体内蓄积多肽的模拟物进行吸附实验.研究表明,吸附剂对多肽模拟物产生一定的吸附作用.在此基础上又对尿毒症患者血清超滤液进行了吸附实验,结果显示,吸附剂对血清中分子级分的清除率为10.3%.     

Regeneration of thiol-functionalized mesostructured silica adsorbents of mercury

The regeneration of thiol-functionalized SBA-15 adsorbents of mercury is presented in this article. The influence of temperature and pH on the adsorption process was studied. The effect due to the presence of complexing agents in aqueous solution on the desorption step was also evaluated. Hg(II) maximum adsorption capacities at different temperatures ranging from 20 °C to 60 °C were obtained and it was found that temperature does not affect the adsorption process. Mercury adsorption capacity was also determined in the presence of HNO₃ and HCl up to 3 M concentration. The comparison of the results showed that whereas hydrochloric acid exhibits an appreciable capacity to regenerate the thiol-functionalized SBA-15 adsorbent, the nitric acid results inefficient. The difference was attributed to the mercury complexing ability of chloride anion. Four complexing compounds, KBr, KSCN, (NH₂)₂CS, and HBr were tested for desorbing mercury in regeneration experiments. All agents were able to remove significant amounts of adsorbed mercury, being hydrobromic acid the complexing compound that yields the best results.     

Screening of Factors Influencing the Adsorption of Methylene Blue Aqueous Solution onto Raw Maize Cobs Using Fractional Factorial Design

Fractional factorial design is used to identify the significant variables that have large effects on the COD reduction and decolorization of methylene blue dye aqueous solution, through adsorption process. Four factors (pH, adsorbent dosage, temperature, and contact time) were screened by using the 2⁴ fractional factorial designs. The results showed that all the main factors have first-order interaction effects and second-order interaction effect, which were significantly affecting decolorization and COD reduction. Results obtained indicated that fractional factorial design can be used as a method to screen a large number of factors and to reduce the number of experimental runs.     

生物大分子的传质与分离

创建了 ＲＳＡ－ＬＲＳ理论，建立起新的吸附动力学方程，应用到涉及特殊生物大分子吸附 的数学模型中去．计算结果与实验测定值相吻合，表明适用于描述类似于ＬＤＬ及ＶＬＤＬ这类 生物大分子的吸附过程．     

球型木质素碳化树脂的制备及性能研究

利用酸法制浆的木质素磺酸盐废液合成的球形木质素阳离子交换树脂，直接制备水质素碳化树脂；考察了碳化条件，运用电子显微镜、热重分析、Ｘ射线衍射等仪器对木质素碳化树脂的结构、碳化失重、孔结构、比表面和吸附量等性能进行了研究。研究结果表明：氯化锌法制备球状木质素碳化树脂的最优工艺条件为，碳化时间０．５ｈ、碳化温度４００℃、活化时间１ｈ、活化温度５００℃。碳化树脂的比表面为 ３８２．３ｍ２／ｇ，亚甲基兰吸附量为 １３２．６ｍｇ／ｇ。球形木质素碳化树脂具有丰富的孔结构，物理化学性能良好。     

Biochar derived from waste bamboo shoots for the biosorptive removal of ferrous ions from aqueous solution

With the ongoing global demands for modern commodities, anthropogenic activities by industries and humans have brought a colossal pressure to the natural water bodies. Though numerous scientific interventions or treatment techniques have been proposed, the need for a viable low-cost method has been a quest for many researchers. Adsorption as such has been in the limelight as an effective method in recent times using various feedstock biomass waste. Our present piece of research aims to use the non-edible biomass waste generated from bamboo shoots as a sustainable low-cost biochar adsorbent and examine its efficiency in the removal of ferrous (Fe²⁺) ions from an aqueous solution. The batch adsorption study was conducted and the optimum dose and concentration were found to be 0.2 g and 7 mg L^?1 with the Langmuir isotherm model best describing the experimental data. Furthermore, kinetic study suggests that the overall sorption rate predominantly follows the chemisorption pathway. Multiple studies suggest bamboo is an excellent adsorbent for treating various inorganic & organic contaminants; here we have highlighted the multifaceted applications of waste bamboo shoots as an effective adsorbing material. The obtained results can lead to additional benefits and usage of bamboo shoots (waste) with future research prospects.