蜡梅花头香的富集及其化学成分研究

用顶空和不同吸附剂吸附法收集蜡梅花的头香,并用GC-MS法对其进行了化学成分研究。对比了不同吸附剂在相同条件下对蜡梅花头香的吸附量与吸附成分。结果表明,不同吸附剂吸附的头香量和化学成分不同。大孔树脂的吸附量是0.22 g,且不具有蜡梅花香味,是自身分解物;阳离子交换树脂、凹凸棒石、活性炭、分子筛吸附量分别是0.52、0.42、0.26、0.29 g,检测出的化学成分种类分别是27、24、12、10种,且与蜡梅花的香味相似;后4种吸附剂所吸附的头香总成分约39种。凹凸棒石和阳离子交换树脂是蜡梅花头香成分的适宜吸附剂。     

Nontraditional method for the preparation of carbon sorbents from composites based on phenol-formaldehyde resins

A technology for the preparation of high-strength carbon sorbents based on phenol-formaldehyde resins with the use of microwave energy at the stages of the carbonization of starting raw materials, the activation of carbonization products, and the regeneration of spent sorbents was developed. These sorbents were effective in a pulp countercurrent process for the recovery of noble metals. The physicomechanical, structural, and adsorption characteristics of the resulting sorbents were tested.     

Porous carbon/carbon composites produced from carbon black and petroleum pitch

Granular porous carbon/carbon composites were prepared by mixing carbon black, petroleum pitch and a solvent, followed by granulating the mixture and carbonization of the resulting pellets in an inert atmosphere. The pore structure of this material is studied by mercury porosimetry and scanning electron microscopy. Based on the obtained results, a model for it is proposed. The effects of carbon black type used, filler/binder ratio, heat treatment temperature and mixing time on surface area, total pore volume and strength of the finished pellets were investigated. Comparison with activated carbons indicates that the investigated material can find industrial applications as a catalyst support and as an adsorbent for adsorption of large molecules due to the meso- and macroporous structure and low ash content.     

大孔树脂对金银花中绿原酸的纯化研究

考察不同型号的大孔吸附树脂对金银花中的绿原酸的提取纯化效果,为进一步开发金银花的相关产品提供参考。采用HPLC法测定绿原酸含量;选用5种不同型号的大孔树采用静态吸附法,筛选出吸附效果和解吸效果较好的大孔吸附树脂;采用动态吸附法,考察大孔树脂的吸附、解吸附性能和纯化效果。NKA-9大孔树脂综合性能最佳,提取液在酸性条件下吸附量最佳。NKA-9大孔树脂对绿原酸的提取纯化效果较好,可用于工业化生产。     

Preparation of carbon sorbents from certain types of biomass

An integrated study of olive pits and walnut shells as raw materials for conversion into carbon sorbents was performed. The results of thermogravimetric studies and proximate and ultimate analyses of the raw materials allowed us to choose a processing technique and the performance characteristics of carbonization. The sorbents based on the test plant waste materials were found to exhibit high strength and well-developed pore structure with a high specific surface area of micropores and sufficiently developed mesoporosity. These sorbents were superior to high-quality active carbons in terms of adsorption capacity for substances with various molecular sizes.     

Preparation of macroporous carbons from phase-inversion membranes

Preparation of porous carbons from phase-inversion membranes was investigated as a control method of pore structure in carbon materials. The structure in carbon films was estimated by means of electron microscopy, mercury porosimetry, and gas-adsorption methods. When phase-inversion membranes of Kapton-type polyimide were carbonized, they maintained the film form and gave macroporous carbon films having high porosity. However, micro- and mesopore structures in the carbon films were not influenced by phase inversion in the polymer stage, and, thus, the macroporous carbons had a molecular sieve property similar to that of carbons prepared from nonporous polyimide films. A macroporous structure in cellulose membranes was similarly maintained through the carbonization step, but some of these were fractured or deformed owing to the large shrinkage. Polymer membranes have a capability as porous carbon precursors if they satisfy two requirements: solid-state carbonization and relatively high carbon yield. A composite membrane of a macroporous carbon with a dense carbon having an impervious ability was readily produced by shaping at the precursor stage. © 1995 John Wiley & Sons, Inc.     

Adsorption method for the recovery of hydrocarbons from natural gas and associated petroleum gas

Carbon sorbents were prepared based on various raw materials, and their sorption capacities for gasoline fraction were studied under static and dynamic conditions. A pilot batch of the most efficient sorbent was tested in a pilot plant under conditions similar to the operating parameters of commercial natural gas-gasoline processing plants. The dynamic adsorption capacity of a carbon sorbent was higher than this characteristic of imported silica gel, which is commonly used for natural gas stripping.     

Peat-based sorbents for the purification of contaminated environments: A review

The review surveys the most interesting published data on the development of sorbents based on peat and the applicability of these sorbents to the removal of petroleum, petroleum products, metals, surfactants, etc., from contaminated environments. Peat is an inexpensive, accessible, and effective sorbent for a wide range of biosphere pollutants. It can be used either individually or as a constituent of combined sorbents and complex composite materials.     

Carbon adsorbents from shale tars and phenols

Carbon sorbents were prepared in a commercial process based on shale tars and phenols. The sorption properties of these sorbents were better than those of commercial sorbents in the sorption of various products: 95–98% for refinery molasses, 311–315 mg/cm³ for benzene, 326 mg/g for phenol, and 40 cm³/cm³ for carbon monoxide.     

纳米结构多孔固体在二氧化碳吸附分离中的应用

二氧化碳（CO2）的双重角色（温室气体及一碳化工原料）使其吸附分离研究具有重要学术及社会经济意义。本文以多孔吸附材料为主线,系统评述了多孔炭、分子筛、有机金属骨架类材料及多孔聚合物等的CO2吸附分离最新研究进展。这些吸附材料的特点：多孔炭的微观及宏观形貌可控,孔结构可调,稳定性好;分子筛的具有丰富的微孔,孔径分布集中;有机金属骨架及多孔聚合物的种类多样,代表一类新兴的CO2吸附材料。分析了多孔固体应用于CO2吸附分离所涉及的关键科学问题,即高效吸附材料立体设计及影响选择性和吸附量等重要参数。提出澄清微孔/介孔/大孔比例以及表面基团种类和数量对CO2吸附贡献的定量关系的必要性,对材料的定向合成与优化有重要指导意义。     

壳聚糖/活性炭复配水处理剂制备及应用研究

采用微波法制备了交联壳聚糖,与活性碳复配得到复合吸附剂,并研究其对水中卤化物的吸附效果。结果表明,微波法制备复合交联壳聚糖吸附剂简化了制备工艺,且吸附效果较好。     

Modification of CaO-based sorbents prepared from calcium acetate for CO2 capture at high temperature

CaO-based sorbent is considered to be a promising candidate for capturing CO_2 at high temperature. However,the adsorption capacity of CaO decreases sharply with the increase of the carbonation/calcination cycles. In this study, CaO was derived from calcium acetate(CaAc_2), which was doped with different elements(Mg, Al,Ce, Zr and La) to improve the cyclic stability. The carbonation conversion and cyclic stability of sorbents were tested by thermogravimetric analyzer(TGA). The sorbents were characterized by N_2 isothermal adsorption measurements, scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results showed that the cyclic stabilities of all modified sorbents were improved by doping elements, while the carbonation conversions of sorbents in the 1st cycle were not increased by doping different elements. After 22 cycles, the cyclic stabilities of CaO–Al, CaO–Ce and CaO–La were above 96.2%. After 110 cycles, the cyclic stability of CaO–Al was still as high as 87.1%. Furthermore, the carbonation conversion was closely related to the critical time and specific surface area.     

粉末活性炭应急处理水源石油类污染的试验研究

针对城市水源可能突发的水体石油类含量超标,以小试试验为基础,模拟珠江广州段西航道水源石油类超标进行城市供水应急处理试验研究。结果表明:在原水中石油类含量超标约3倍时,给水厂常规工艺与粉末活性炭吸附单独处理两者效果均不理想,而在原有常规工艺前投加粉末活性炭进行吸附预处理,FeCl3投加量60mg/L,活性炭投加5mg/L,吸附10min条件下,石油类去除率达75.5%,处理后出水石油类的质量浓度低于0.05mg/L,可达地表水环境质量Ⅲ类标准。     

Dithiocarbamate-incorporated monodisperse polystyrene microspheres as specific sorbents: Adsorption of cadmium ions

In this study, adsorption of cadmium ions from aqueous solutions by using dithiocarbamate-incorporated monodisperse crosslinked polystyrene (PS)-based sorbents was investigated. Monodisperse PS microspheres with a diameter of 2 μm were produced by dispersion polymerization of styrene in isopropyl alcohol/water by using polyvinylpyrrolidone and azobisisobutyronitrile as stabilizer and initiator, respectively. These microspheres were then crosslinked by using divinylbenzene. In order to incorporate dithiocarbamate functional groups on the PS microsphere, first benzylamine was physically absorbed, then the amine groups were transformed into dithiocarbamate groups by interacting these microspheres with carbon disulphide. These PS-based sorbents carrying physically entrapped benzyl dithiocarbamate were characterized by scanning electron microscopy, optical microscopy, FTIR, and elemental analysis. Adsorption of cadmium ions on the PS-based sorbents were investigated in the batch equilibrium experiments by using atomic absorption spectrophotometer. Adsorption rates were very fast. Adsorption equilibria were achieved within 5-60 min. The highest adsorption capacity achieved was 154.1 mg cadmium/g sorbent. The most suitable pH was 6.0. © 1996 John Wiley & Sons, Inc.     

固体二氧化碳吸附剂研究进展

大量化石燃料的燃烧造成二氧化碳等温室气体的过量排放,严重影响了全球的环境与气候变化。固体吸附剂由于易处理、能重复使用、原材料损耗小而受到二氧化碳捕集领域的广泛关注。主要针对近些年来发展起来的新型固体二氧化碳吸附剂优缺点进行了分析比较。根据其吸附温度的不同,分别以低温、中温和高温3类吸附剂进行分类讨论。重点讨论了高温固体钙基吸附剂的吸附性能,以及其常见的改性方法,由于其吸附量高、原材料丰富、成本低等优点,氧化钙基吸附剂被认为是最理想的高温吸附剂。     

大孔吸附树脂精制鱼腥草黄酮类化合物

Flavonoids are one main kind of effective components in Houttuynia cordata Thunb., which display a wide range of pharmacological activity. In this study supercritical fluid extraction （SFE） with carbon dioxide was first used as preparat ion step to remove the volatile components, which are also active components, from Hout-tuynia cordata Thunb. Then ultrasound-assisted extraction was used to obtain the crude flavonoids and the macro-porous resin adsorption technology was further employed to purify the flavonoids. Nine kinds of macroporous resins with different properties were tested through static adsorption, and one macroporous resin labeled as D101 was selected. The effect of several factors, such as the ratio of column height to diameter, initial concentration and pH, on both flavonoids yield and content were explored by dynamic adsorption to obtain reasonable conditions of adsorption and desorption. The experimental results show that the content of fiavonoids can be above 60% with fia- vonoids recovery of 93.3 % under the optimum conditions of purification. HPLC analysis of the final flavonoids product shows it contains quercitrin, hypefin, rutin and quercetin.     

Nitrogen adsorption on carbonaceous materials: A comparison between static and dynamic methods

The purpose of this study was to investigate the influence of the method of adsorption of N₂ at − 196 °C on the isotherm obtained for, and hence derived textural parameters of, a wide series of carbonaceous materials (CM). Two pyrolyzed products, six activated carbons and two carbon blacks were used. The carbonized products were prepared by pyrolysis of cherry stones at 600 or 900 °C in nitrogen atmosphere (P-600, P-900). Three activated carbons were made by activation of P-600 at 275 °C in air and of P-900 at 850 °C in carbon dioxide or steam, whereas the remaining CM were commercial products. The adsorption isotherms for N₂ at − 196 °C were determined by static and dynamic methods in Quantachrome equipments. The CM were further characterized texturally by means of mercury porosimetry and helium and mercury density measurements. Because of the presence of helium in the adsorptive gas stream, the adsorption of nitrogen noticeably decreases for the CM containing micropores obstructed with tarry products (i.e. P-600 and the activated carbon prepared from it by air activation). For the rest of the activated carbons the adsorption increases, as they must possess narrow micropores having easier access to N₂ at − 196 °C. Helium causes a decrease in the degree of interaction between the nitrogen molecules in the gas stream and as a result the diffusion of nitrogen in pores of the adsorbent increases. For the carbon blacks, however, helium hardly affects the adsorption of nitrogen, except for at high relative pressures of this gas. Helium also influences the capillary condensation phenomenon occurring in mesopores. The variation percentages in the micro- and mesopore volumes are as high as 20 and 50, respectively. Such percentages as a rule are higher for the activated carbons.     

The removal of the acetonitrile using activated carbon-based sorbent impregnated with sodium carbonate

To remove acetonitrile, various activated carbon (AC)-based sorbents impregnated with alkali or alkaline earth metal were tested in a fixed-bed quartz reactor at 30 °C. The AC-based sorbents impregnated with sodium (NaAC) showed more enhanced acetonitrile removal capacities than that of the pure AC sorbent despite a notable decrease in their surface areas and pore volumes. The NaAC-10 sorbent (with 10 wt% sodium carbonate) especially showed an excellent acetonitrile removal capacity (15mg CH₃CN/g sorbent) and regeneration ability, which indicates that the alkali metal was the adsorption site of the acetonitrile.     

钙基CO2吸附剂的惰性掺杂和形貌调控研究进展

有效捕集CO₂对于缓解亟待解决的温室效应、气候变暖、环境污染和能源危机问题具有重大意义。钙基吸附材料因为CO₂吸附容量高及成本低廉而受到了广泛关注。本文介绍了钙基吸附剂的CO₂吸附机理,着重阐述了显著提高吸附性能的两种改性方法,包括惰性掺杂和形貌调控。归纳了利用Zr、Ce、Mn、Mg、Al等塔曼温度较高或富含氧空穴的金属氧化物对氧化钙进行单掺杂和复合掺杂改性,针对合成方法、吸脱附条件、惰性组分掺杂量、钙基前体等不同参数对掺杂改性钙基CO₂吸附剂性能的影响进行总结。同时指出,采用聚苯乙烯小球、碳凝胶、碳球、表面活性剂等制备得到的中空结构球形钙基吸附剂或实心结构球形钙基吸附剂,具有良好的CO₂吸附容量和吸附稳定性。提出两种改性方法距离工业化应用还有较大的差距,亟需深入探讨吸附剂的结构与性能之间的关系,从而为吸附剂的设计提供理论指导。     

油品蒸发损耗及油气回收技术

石油及其产品在加工和储运过程中产生的蒸发损耗是困扰石油加工储运和环保行业的重要课题,推广和采用油气回收技术十分迫切和重要。本文介绍了常见的4种油气回收技术吸附法、吸收法、冷凝法和薄膜选择渗透法,分析了各种油气回收方法的发展方向,特别介绍了活性碳纤维作为新型油气回收吸附材料的应用前景。