活性炭纤维的吸附效果研究及在空气净化方面应用

介绍了活性炭纤维的特性、用途。以及对活性炭纤维进行了吸附效果的实验研究。结果表明，活性炭纤维因其比表面积大，微孔丰富，阻力小使气体或液体容易通过而对有机物具有较高的平衡吸附容量和良好的吸附能力。本文还叙述了活性炭纤维在空气净化方面的功用     

活性炭纤维吸附性能测定及其应用

活性炭纤维吸附性能测定及其应用江苏省卫生防疫站（南京２１０００９）张秀珍李延平徐强吴玉珍匡国正南京市鼓楼区卫生防疫站赵龙建冼海林活性炭纤维是近年发展起来的一种新型过滤材料，它的开发应用受到许多国家的重视，对于油漆、涂料及各种日用化学品等挥发出的有机物...     

离子交换纤维除氟初试

本文就使用Vs—5螯合型离子交换纤维除氟进行了初步试验,结果表明,在生活饮用水除氟方面优于目前国内采用的活性炭法、铅盐絮凝法,具有选择性好,吸附容量大,运行稳定,操作简单等优点。     

三种国产活性炭吸附去除水中病毒能力的比较

目的 开展饮用水的深度处理,比较几种常用的国产活性炭在不同条件下吸附去除水中病毒的能力.方法 采用三角瓶实验比较了两种国产椰壳颗粒活性炭和一种国产粘胶基纤维活性炭毡在设定条件下(磷酸盐缓冲液,pH=7.3,25℃)去除病毒的能力以及其中一种椰壳颗粒活性炭在不同条件下(预处理前后,温度15～35℃,pH=6.0～8.4,钙离子浓度为0～500 mg/L,离子强度为0～0.1 mol/L)去除病毒的能力.实验病毒为从污水中富集的大肠杆菌(Escherichia coli285)噬菌体指示病毒.结果 颗粒活性炭去除病毒的过程较好地符合一级反应动力学(R2=0.83～0.99),而纤维活性炭的符合程度较差(R2=0.44～0.64),速率常数为0.505 3～2.606 8(颗粒炭)和0.219 2～0.413 8(纤维炭);预处理活性炭(用去离子水煮沸2 h后冲洗)即可增强又可减弱病毒的去除效果,取决于活性炭来源;两个厂家生产的椰壳颗粒炭在去除病毒的效果上有较大差异,其相对强弱取决于有无预处理;较高的温度和钙离子浓度或离子强度以及偏酸偏碱条件通常加快颗粒炭对病毒的去除.一级动力学模拟计算表明,15 min内去除率约为30%,最高为40%,最低为5%;在实验5 h内的最大去除数量为5个对数.实际测定结果显示,虽然颗粒炭的实验用量(1 g)是纤维炭(0.1 g)的10倍,但是后者比前者有更快的初始去除速率.结论 三种国产活性炭在吸附去除水中病毒的效果上有较大差异,其相对强弱取决于实验条件.如果考虑目前水处理技术中较短的活性炭滤池处理时间(大约15min),研究能进一步提高本实验所用的国产活性炭材料在吸附去除病毒方面的能力十分必要.     

光触媒/活性炭-电纺纳米纤维复合膜的制备及其甲醛去除性能的考察

目的为克服现有的室内甲醛污染治理材料存在的不足,将光触媒光催化分解和活性炭物理吸附除甲醛机理相结合,发展可长期、重复使用,并且无需完全依赖光照的甲醛去除材料。方法选取聚氯乙烯PVC+聚苯乙烯PS为基质,以DMF+THF(3+1)为溶剂制备电纺纳米纤维膜(NF),采用电喷雾的技术逐层在纤维表面沉积光触媒(P)和活性炭(C),得到三元复合材料,进一步通过交替电纺和功能化,得到NF-P/C复合多层膜。对制备的复合膜NF-P/C膜与NF-P膜及NF-C膜在有无光照条件下甲醛去除性能进行考察,并与几种市售甲醛去除剂进行甲醛去除性能上的对比。结果在500 W氙灯照射下12 h内光催化甲醛去除效率比纯Ti O2光触媒的更为优异,而在无光照的条件下仍能保持良好的甲醛去除效率。结论 NF-P/C三元复合膜在有无光照的条件下均能表现出优秀的甲醛去除性能。     

具有灭菌功能碳吸附材料的研究

本文论述的是以活性炭纤维为载体,制备具有灭茵功能的复合炭吸附材料——载银活性炭纤维的研究工作。文中阐述了沥青予氧丝碳化、活化工艺和用分解法在其上沉积微晶银的操作过程;用电子显微镜、X线衍射、X线光电子能谱测定、分析予氧丝、活性炭纤维、载银活性炭纤维的形貌、结构和成分;用BET法测试这些材料的物理吸附性能;进行了载银活性炭纤维对水中大肠埃希氏杆菌杀灭功能的试验结果。实践证明,这种碳吸附材料在水净化,消毒领域将具有广阔应用前景。     

降低生活饮用水总α放射性的研究

本文研究了铁盐、铝盐混凝及活性炭吸附去除水中α放射性的效果。结果表明，以铀为示踪剂，在水中Ｆｅ＾３＋、Ａｌ＾３＋浓度分别为３０．６０ｍｇ·Ｌ＾－１时，形成沉淀对α放射性的载带去除率分别为１０．３％、１７．４％；在用粉末状活性炭吸附，当每升水中活性炭加入量为１ｇ时，吸附去除α放射性达８３．５％．重点研究了粉末状活性炭去除水中α放射性的最佳条件，最制定了一个实用的降低饮水中总α放射性的程序。     

人工肾用新型球形活性碳的制备及其特性研究

为研究小型人工肾,研制了一种新型球形活性炭(SAC)。文章论述了原料树脂热行为与SAC结构之间关系,及SAC的结构与对肌酐、尿酸和VB_(12)吸附特性间的关系。实验表明,SAC表面积增加则其吸附性能提高;原料树脂的吸附性能加大则SAC的吸附性能亦提高。由活体动物(犬)小型柱血液灌流实验测定二种活性炭(SAC和进口炭BAC—MU)对血液有形成份等项指标的影响。结果表明,SAC由于球形好,强度高,表面光滑,它具有较好的血液相容性和极少的微粒脱落。它的吸附性能和BAC—MU相当。     

地方性氟中毒致机体损伤的研究进展

地方性氟中毒是指生活在由自然或人为污染所致高氟环境中的居民, 因体内摄入过量氟化物而引起的一种地方性疾病。氟斑牙、氟骨症是地方性氟中毒较常见的症状;此外, 长期氟暴露还可引起神经系统、心血管系统、泌尿系统等多个系统的损伤, 最终导致全身多器官的慢性病变和功能障碍。目前, 地方性氟中毒仍是我国乃至世界的严重公共卫生问题之一。故本文从骨相和非骨相系统两方面就地方性氟中毒对人群机体损伤的研究进展进行综述, 以期为今后地方性氟中毒的持续防控提供参考依据。     

吸附反应型甲醛去除剂的研制

目的 研究一种能有效去除室内空气中甲醛的去除剂.方法 以活性炭为原料,以KOH为活化剂,通过活化、浸渍,研究了活性炭的粒度、活化时间、活化温度、浸渍时间等对甲醛去除剂吸附量的影响.结果 确定了制备甲醛去除剂的最适宜工艺条件以及吸附甲醛的最佳条件(粒度为100目,碱炭质量比为3:1,活化温度为600℃,活化时间为1.5h,浸渍时间为2h).甲醛去除剂对甲醛的质量吸附率达到49.6%,比表面积1591m2/g,孔容1.01cm3/g,因此经过改性处理的活性炭其质量吸附率、比表面积均大于未处理的活性炭.结论 该甲醛去除剂可有效去除甲醛.     

Adsorption Characteristics of Activated Carbon Fibers (ACFs) for Toluene: Application in Respiratory Protection

Granular activated carbon (GAC) is currently the standard adsorbent in respirators against several gases and vapors because of its efficiency, low cost, and available technology. However, a drawback of GAC due to its granular form is its need for containment, adding weight and bulkiness to respirators. This makes respirators uncomfortable to wear, resulting in poor compliance in their use. Activated carbon fibers (ACF) are considered viable alternative adsorbent materials for developing thinner, light-weight, and efficient respirators because of their larger surface area, lighter weight, and fabric form. This study aims to determine the critical bed depth and adsorption capacity of different types of commercially available ACFs for toluene to understand how thin a respirator can be and the service life of the adsorbents, respectively. ACF in cloth (ACFC) and felt (ACFF) forms with three different surface areas per form were tested. Each ACF type was challenged with six concentrations of toluene (50, 100, 200, 300, 400, 500 ppm) at constant air temperature (23°C), relative humidity (50%), and airflow (16 LPM) at different adsorbent weights and bed depths. Breakthrough data were obtained for each adsorbent using gas chromatography with flame ionization detector. The ACFs’ surface areas were measured by an automatic physisorption analyzer. The results showed that ACFC has a lower critical bed depth and higher adsorption capacity compared to ACFF with similar surface area for each toluene concentration. Among the ACF types, ACFC2000 (cloth with the highest measured surface area of 1614 ± 5 m²/g) has one of the lowest critical bed depths (ranging from 0.11–0.22 cm) and has the highest adsorption capacity (ranging from 595–878 mg/g). Based on these studied adsorption characteristics, it is concluded that ACF has great potential for application in respiratory protection against toluene, particularly the ACFC2000, which is the best candidate for developing thinner and efficient respirators.     

Transmission and control of methicillin-resistant Staphylococcus aureus in a skilled nursing facility

Methicillin-resistant Staphylococcus aureus (MRSA) is increasingly frequent in both acute care facilities (ACFs) and skilled nursing facilities (SNFs). Admissions to SNFs from ACFs with endemic MRSA are one likely source of infection in SNFs. The occurrence of MRSA in SNFs and the relative roles of ACFs and SNFs in MRSA transmission have not been well characterized. We conducted an epidemiologic investigation in an SNF reporting a high incidence of MRSA cases and found that the prevalence of MRSA exceeded that reported in acute care settings. Fifteen (9.1%) of the 164 residents were colonized or infected with MRSA. Risk factors for MRSA identified through a prevalence case-control study were nasogastric intubation (odds ratio = 5.5; 95% confidence interval = 1.2, 26.4), antibiotic therapy (OR = 3.9; CI = 1.2, 13.0), and hospitalization in an acute care facility within the previous six months (OR = 2.9; CI = 0.9, 9.7). During a three-month period, 6 of 100 new admissions were MRSA-positive; all positive patients were from ACFs. Five new cases also emerged from previously MRSA-negative residents. SNF residents are often discharged to ACFs. Transmission of MRSA within the SNF and the transfer of patients to ACFs increases the reservoir of potentially infective patients and the potential for MRSA infections in ACFs. Modest control measures, including targeted surveillance culturing and cohorting of colonized residents, may minimize MRSA transmission in the SNF and decrease the reservoir of MRSA in the community.     

The effect of activated carbon on partitioning, desorption, and biouptake of native polychlorinated biphenyls in four freshwater sediments

The present study evaluated the effect of activated carbon amendment in four freshwater sediments from the Great Lakes (North America) areas of concern with a wide range of sediment geochemical characteristics (0.83-5.1% total organic carbon) and polychlorinated biphenyl (PCB) concentrations (0.33-84.7 microg/g). The work focused on understanding the impact of activated carbon amendment on PCB aqueous partitioning, PCB desorption characteristics, and PCB biouptake in a freshwater oligochaete (Lumbriculus variegatus). The results showed that PCB aqueous equilibrium concentrations, rapid desorption fractions, and biouptake by the oligochaete were reduced after activated carbon amendment. Addition of activated carbon at a dose of 0.5-fold native organic carbon reduced PCB bioaccumulation by 42% for Niagara River sediment, 85% for Grasse River sediment, 74% for Milwaukee River sediment 1, and 70% for Milwaukee River sediment 2. A linear relationship was observed between log biota-sediment accumulation factor and the first 6-h desorption fractions for each PCB homologue for treated and untreated sediments. Water-lipid bioconcentration factors for PCB congeners were largely conserved after amendment with activated carbon. Our present results suggest that at steady state, changes in the aqueous PCB concentrations can be used to predict changes in PCB bioaccumulation in deposit-feeding organisms. Thus, use of advanced pore-water measurement techniques, such as solid-phase extraction passive samplers, may be suitable for long-term monitoring of treatment performance.     

一次性理疗保健用自发热材料的制备

目的：制备一次性理疗保健用自发热材料。方法：用脲、硫脲、聚乙二醇（PEG）制备了Polymer in Salt型聚合物固体电解质（SPE），将该SPE与还原铁粉、活性炭物理共混制备自发热材料。结果：自发热材料形态为固态，接触空气后释热，不接触空气时处于休眠状态，控制其与空气的接触量可实现热量的控制释放，释热效果良好。结论：SPE与金属粉末、活性炭物理共混可以制备性能优良的固态自发热材料，该材料可用于橡胶硬膏剂或黑膏药的发热裱褙材料、人体热敷材料等一次性医用制品。     

Determination of pressure drop across activated carbon fiber respirator cartridges

Activated carbon fiber (ACF) is considered as an alternative adsorbent to granular activated carbon (GAC) for the development of thinner, lighter, and efficient respirators because of their larger surface area and adsorption capacities, thinner critical bed depth, lighter weight, and fabric form. This study aims to measure the pressure drop across different types of commercially available ACFs in respirator cartridges to determine the ACF composition and density that will result in acceptably breathable respirators. Seven ACF types in cloth (ACFC) and felt (ACFF) forms were tested. ACFs in cartridges were challenged with pre-conditioned constant air flow (43 LPM, 23°C, 50% RH) at different compositions (single- or combination-ACF type) in a test chamber. Pressure drop across ACF cartridges were obtained using a micromanometer, and compared among different cartridge configurations, to those of the GAC cartridge, and to the NIOSH breathing resistance requirements for respirator cartridges. Single-ACF type cartridges filled with any ACFF had pressure drop measurements (23.71–39.93 mmH₂O) within the NIOSH inhalation resistance requirement of 40 mmH₂O, while those of the ACFC cartridges (85.47±3.67 mmH₂O) exceeded twice the limit due possibly to the denser weaving of ACFC fibers. All single ACFF-type cartridges had higher pressure drop compared to the GAC cartridge (23.13±1.14 mmH₂O). Certain ACF combinations (2 ACFF or ACFC/ACFF types) resulted to pressure drop (26.39–32.81 mmH₂O) below the NIOSH limit. All single-ACFF type and all combination-ACF type cartridges with acceptable pressure drop had much lower adsorbent weights than GAC (≤15.2% of GAC weight), showing potential for light-weight respirator cartridges. 100% ACFC in cartridges may result to respirators with high breathing resistance and, thus, is not recommended. The more dense ACFF and ACFC types may still be possibly used in respirators by combining them with less dense ACFF materials and/or by reducing cartridge bed depth to reduce pressure drop to acceptable levels. ACFF by itself may be more appropriate as adsorbent materials in ACF respirator cartridges in terms of acceptable breathing resistance.     

Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia

Aged care facilities (ACFs) are residential communities with a concentration of vulnerable individuals with increased risk of severe influenza infection and complications such as outbreaks, hospitalisations and deaths. Aged care workers (ACW) are potential sources of influenza introduction and transmission in ACFs. Little is known about vaccine uptake among ACW. This study aimed to measure the vaccine uptake rate among Australian ACW and evaluate the demographic determinants of uptake during the influenza season of 2018.146 ACWs were recruited from 7 facilities of a multisite aged care provider in Sydney. ACWs completed a questionnaire regarding their demographic, occupational and vaccination status. Vaccine coverage was calculated and variables were examined against their 2018 influenza vaccination status in statistical analysis.ACWs in our study were predominantly from a non-health occupational background with a large proportion of migrant workers (56%, 75/134). Vaccine coverage in 2018 was 48% (65/135). The strongest determinants of vaccine uptake were previous year vaccination history (Odds Ratio [OR] 10.49, 95% CI 3.33–33.10), workplace immunisation programs for employees (OR 7.87, 95% CI 2.47–25.10), casual work as employment status (OR 0.14, 95% CI 0.02–0.77), and presence of comorbidities (OR 4.04, 95% CI 1.23–13.32).ACW are a unique and understudied group who are critical to infection control in ACFs. Few ACWs have formal health training, and many are migrants who may lack access to subsidised health care and face out of pocket costs for vaccination. Vaccine coverage among ACW were below recommended levels. Provision of influenza vaccine for staff in workplaces is highly effective in raising vaccine coverage amongst ACWs. More research on the aged care sector workforce is needed in order to evaluate the determinants of vaccine uptake among Australian ACWs.     

Estimating service lives of air-purifying respirator cartridges for reactive gas removal

A mathematical model has been developed to estimate service lives of air-purifying respirator cartridges that remove gases reactively from flowing air. Most gases, because of their high volatility and low polarizability, are not effectively removed by physical adsorption on activated carbon. Models previously developed for toxic organic vapors cannot estimate service lives of cartridges for toxic gases. Often, an activated carbon is impregnated with a chemical to enhance gas removal by chemical reaction(s). The kinds of reactions, types and amounts of impregnants, and effects of the presence of water vary; therefore, the model requires user inputs of gas capacity and water effect parameters. Ideally, these should be available from manufacturers of the cartridges. If they are not, they can be extracted from measured breakthrough times using this model. The key to this model is the observation that adsorption rates of gases can be adequately quantified by the same correlations that have been reported for organic vapors. The resulting model has been used to correlate and predict breakthrough times for several common toxic gases.     

Isolation of green coffee chlorogenic acids using activated carbon

Chlorogenic acids, which are interesting natural antioxidants widespread in the plant kingdom, were extracted and purified from Mexican green coffee beans (Coffea arabica) using different methods. The final objective was to find an easy way to extract high-value molecules from a complex mixture, avoiding as much as possible the use of toxic solvents. Three extraction methods (hot water at 80 °C, aqueous methanol 70% (v/v), and aqueous isopropanol 60% (v/v)) were tested in combination with two isolating methods (activated carbon, different solvents). The extracted amounts of chlorogenic acids with the six treatments (4.67–5.87% dry basis) presented no significant differences. The one using hot water for extraction and of activated carbon for isolation, was the simplest and the most environmentally friendly. Thus it can be used as a previous step to obtain from green coffee a mixture rich in chlorogenic acids which can be further fractionated to purify a specific chlorogenic acid (i.e. in this work, 5-O-caffeoyl quinic acid using a silica gel column). Chlorogenic acids can be used as natural antioxidants in food or non-food products. To the best of our knowledge, activated carbon has not been used to isolate chlorogenic acids from green coffee.     

Evaluation of activated carbon filters for removal of ozone at the PPB level.

Performance of filters for the removal of ozone at ambient concentration is characterized. The removal efficiency and pressure drop of 10 commercial filters--including 8 made of granule or powdered activated carbon, 1 activated carbon fiber filter, and 1 packed bed made of an ozone catalyst--were measured for an influent ozone concentration of 120 ppb at 50% relative humidity and 2.54 m/sec face velocity. Activated carbon filters can be very effective at ozone removal, although not indefinitely because chemical reactions of ozone and carbon change the carbon. Initial efficiencies of the 1.27-cm thick flat samples varied from 4.6 to 98.3%. Analysis of the structure and composition of the filters with scanning electron microscopy and X-ray photoemission spectrometry showed chemical reactions permanently changed the composition of the carbon and decreased the surface area. Consequently, removal efficiency decreased with use. Moreover, it was not feasible to regenerate the filters by simply removing them from ozone-laden air. Changes in relative humidity, from 20 to 80%, had no measurable effect on the performance of a granule activated carbon filter. However, because the rate of adsorption of water is faster and the pores are smaller in activated carbon fiber, efficiency of the fiber filter decreased when relative humidity was raised from 20 to 50%. A quality factor, equal to the ratio of a threshold breakthrough time and pressure drop, is used to compare filters. In general, those with higher carbon surface area per unit volume had higher efficiencies and greater pressure drops. Future work should address the removal of ozone in the presence of other gases.     

A passive diffusion 222Rn sampler based on activated carbon adsorption

A simple passive sampler for 222Rn with up to 24-hr integration times can be constructed by using a diffusion barrier to regulate the effective sampling rate of an ambient temperature activated carbon bed. The diffusion element serves to make sampler performance relatively independent of the properties of the type of carbon used. Satisfactory results are obtained if the total effective sample volume is kept well below the equivalent air volume of the activated carbon bed. The influence of various temperature and Rn profiles on the sampler's performance have been examined by experiment and by simulation. The amount of Rn adsorbed may be measured by gamma spectroscopy, by outgassing into an alpha scintillation flask, or by desorption into a liquid scintillator. In the latter case, a sensitivity of 0.2 pCi l-1 is obtainable for 24-hr exposures.