对氨基苯甲酸生产废水的树脂吸附预处理

采用超高交联吸附树脂处理芳香两性化合物对氨基苯甲酸(PABA)生产废水,通过静态吸附、动态吸附-脱附实验,研究确定了最佳的吸附-脱附工艺条件。结果表明,在常温和2 BV/h的吸附流量条件下,原废水不用调节pH值,直接经JX-101树脂吸附处理20 BV后,CODC r可从6 000 mg/L左右降至700 mg/L左右,CODC r去除率达88%以上,PABA的吸附去除率达99%以上。采用1 BV 8%氨水溶液 1 BV 4%氨水溶液 2 BV水作脱附剂,在313 K脱附温度和1 BV/h脱附流量的条件下,树脂脱附性能良好。该工艺简单,运行稳定,操作简便,可回收有用物质,有望实现工业化。     

污泥含炭吸附剂的制备工艺优化及性能表征

采用先活化剂浸泡活化在干燥热解炭化的化学活化法制备污泥含炭吸附剂.实验结果表明,有机污泥在活化温度为450℃、ZnCl2药剂和干泥质量比为0.7:1、活化时间为1.5 h、锯末添加剂投加量为2%的条件下,制得的含炭吸附剂碘值在510 mg/g以上,收率>60%,比表面积>390 m2/g.由扫描电镜观察可见孔径分布以微孔和中孔为主.     

Minimization of organic chemical load in direct dyes effluent using low cost adsorbents

The work is carried out to minimize the organic chemical load (unexhausted dye contents) in direct dyes effluent using low cost adsorbents. The studies are made with different direct dyes, i.e. Direct Red 28, Direct Yellow 12, Direct Orange 26 and Direct Blue 1 with various adsorbents. Three different bio/natural materials have been selected as adsorbents. These includes, Sugarcane bagasse pith (SB), Saw dust (SD)—the plant origin products, and Brick powder (BP)—a silica based material obtained from earth's crust on thermal heating. These substances are almost discarded waste products with the possibility of use as adsorbents. Experimental work for the dye removal from the effluent by activated charcoal (AC) has also been carried out and the results are compared with other adsorbents. The amount of unexhausted organic dye present in the effluent is measured as chemical oxygen demand (COD) before and after the treatment. Adsorbent Sugarcane bagasse pith shows good performance as compared to Saw dust and Brick powder. For understanding the behaviour of adsorbents Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) has also been carried out.     

Radon emanation from radium specific adsorbents

Pilot studies were undertaken to quantify the total activity of radon that is eluted following no-flow periods from several Ra-226 adsorbents loaded to near exhaustion. The adsorbents studied included two types of barium sulphate impregnated alumina (ABA-8000 and F-1) and Dowex MSC-1 resin treated by either barium hydroxide or barium chloride. In parallel, radium loaded plain activated aluminas and Dowex MSC-1 resin were similarly investigated. The results revealed that radon was quantitatively eluted during the first few bed volumes of column operation after no-flow periods. Although similar radon elution profiles were obtained, the position of the radon peak was found to vary and depended on the adsorbent type. Radon levels up to 24 and 14 kBq dm⁻³ were measured after a rest period of 72 h from radium exhausted Dowex MSC-1 treated with barium chloride and F-1 impregnated alumina with barium sulphate, respectively. The eluted radon values measured experimentally were compared to those calculated theoretically from accumulated radium quantities for the different media. For plain adsorbents, an agreement better than 10% was obtained. For treated resin-types a consistency within 30% but for impregnated alumina-types high discrepancy between respective values were obtained.     

Evaluation of solid sorbents as a retrofit technology for CO2 capture

Processes based upon solid sorbents are currently under consideration for post-combustion CO₂ capture. Twenty-four different sorbent materials were examined on a laboratory scale in a cyclic temperature swing adsorption/regeneration CO₂ capture process in simulated coal combustion flue gas. Ten of these materials exhibited significantly lower theoretical regeneration energies compared to the benchmark aqueous monoethanolamine, supporting the hypothesis that CO₂ capture processes based upon solids may provide cost benefits over solvent-based processes. The best performing materials were tested on actual coal-fired flue gas. The supported amines exhibited the highest working CO₂ capacities, although they can become poisoned by the presence of SO₂. The carbon-based materials showed excellent stability but were generally categorized as having low CO₂ capacities. The zeolites worked well under dry conditions, but were quickly poisoned by the presence of moisture. Although no one type of material is without concerns, several of the materials tested have theoretical regeneration energies significantly lower than that of the industry benchmark, warranting further development research.     

Screening of Inorganic Adsorbents for Selective Adsorption of Thiophene from Model Gasoline

Hydrodesulfurization-treated (HDS-treated) gasoline with low sulfur content is an important source of primary fuel for fuel cells, although it contains sulfur compounds, thiophene (TP), benzothiophene (BTP), and thiophene alkylated derivatives, known as a poison for the reformer catalysts and the electrode catalysts of fuel cells. Adsorptive removal of TP from model organic liquid of HDS-treated gasoline was screened on different kinds of inorganic adsorbents: hydrous metal oxides, mixed metal oxides, aluminosilicates, acidic salts of multivalent metal, hetero polyacidic salt, and metal salts of iron hexacyanate. All the adsorbents showed very low TP uptake, less than 5% of the total TP amount when metal ions were not loaded on the adsorbent. On the other hand, some metal ion (Ag, Cu, and Ce) loaded adsorbents had good TP adsorptive properties. On simple metal oxides, Ag ion was better for the formation of adsorption center than Ce or Ni ions. In zeolite group, Ce-loaded Y-zeolite showed the largest TP uptake (99% of the total TP amount). Hydrous cerium oxide and the Ce-loaded adsorbents prepared from K₄[Fe(CN)₆], Silicagel, TiO₂, and ZrO₂ did not show TP selectivity. The effect of coexisting toluene on TP adsorption was studied from the TP solutions with and without toluene.     

THE WETTABILITY OF LOW COAL RANKS IN THE PRESENCE OF N-ALKANES AND DIACETONE ALCOHOL

ABSTRACT

Contact angle measurements were carried out in coal ranks of 32.1 and 32.2/n-alkane film - air bubble - aqueous diacetone solution systems. In these studies n-alkanes in homological series from n-hexane to n-hexadecane and aqueous diacetone alcohol solutions in concentration range from 0 to 10% were used. On the basis of obtained results the adhesion work of aqueous diacetone alcohol solutions to coal surface precovered with n-alkane film was calculated from the modified Young equation. These investigations showed that an increase of n-alkane film thickness causes a decrease of the wettability of low-rank coals as well ob a decrease of the adhesion work of aqueous diacetone alcohol solutions to coal/n-alkane film surface. An increase of the may be also stated, that an increase of the quantity of diacetone alcohol molecules adsorbed on coal surface precovered by a small amount of hydrocarbon causes a decrease of the adhesion work, but when the coal surface is precovered by a big amount of hydrocarbon the adhesion work is increased.

From the practical point of view it seems to be the most profitable circumstance when a thick n-alkane film occurs on coal surface and a small amount of diacetone alcohol is present in water. However, in order to confirm this more detailed studies in this field should be carried out.     

非金属矿物吸附剂在水处理方面的应用

粘土类非金属矿物具有良好的吸附和离子交换性能,在水处理方面有广阔的应用前景。各国研究者都对它们展开了大量的研究,以期取代价格昂贵的活性炭。本文介绍了几种常见矿物吸附剂的研究现状。     

表面离子印迹聚合物金属离子吸附材料研究进展

离子印迹聚合物吸附材料对模板离子具有强识别能力,对其可实现高选择吸附,因而离子印迹技术常用于制备高选择性吸附材料。但传统方法制备的离子印迹吸附材料,因识别位点容易被包埋导致其吸附容量小、吸附-脱附速率低,而表面离子印迹技术则是采用模板离子和聚合单体直接在载体表面或附近区域构筑选择性识别位点,所有活性位点均暴露,从而有效地解决了上述问题。本文从技术原理与合成原料、制备工艺方法以及载体材料类型等方面对表面印迹聚合物吸附材料近期研究进展情况进行了概述。针对相关研究现状,从载体材料、功能单体、目标离子等角度分析和讨论了表面离子印迹聚合物吸附材料当前发展中的不足及其所面临的挑战,并对表面离子印迹技术发展趋势和前景进行了展望。     

滴定-凝胶法制备球形水凝胶吸附材料及其在废水处理中的应用

滴定-凝胶法制备球形水凝胶吸附材料具有3D倒漏斗状微观形貌结构,孔径分布宽泛,对水体中重金属、染料等污染物具有快速响应机制,已被广泛用于水处理过程研究。综述了滴制法制备球形水凝胶吸附材料的主要过程机理、水凝胶具有的特殊形貌结构及其在水处理过程中的应用,分析了球形水凝胶吸附材料在水处理应用过程中存在的问题和局限,并指出了其在水处理领域的应用前景及发展方向。