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1.
黄凯兵  施敏  李伟  周洪 《功能材料》2013,44(10):1422-1427
采用种子乳液聚合法合成聚甲基丙烯酸甲酯-丙烯酸丁酯(P(MMA-BA))乳液,再将乳液进行喷雾干燥制备了壳层由纳米粒子构成且具有中空形貌的单孔高分子微球。研究了微球形成机理,并着重探讨了预聚物用量、硬软单体配比m(MMA)∶m(BA)、交联剂用量对微球形貌、比表面积的影响。结果表明,当条件为乳液浓度2%,进口温度125℃,出口温度50℃,进料量250mL/h,预聚物用量为2%(质量分数),硬软单体比m(MMA)∶m(BA)约为7∶3,交联剂用量为10%~20%(质量分数)时,能够形成形状规整的中空微球,用BET法测得其比表面积约为28.8259m2/g。考察了中空微球对低浓度苯酚溶液的吸附性能,结果表明,微球对苯酚的最大吸附量可达7.8568mg/g;微球用量较少时,单位质量微球吸附的苯酚量较大;微球中硬单体比例越高,所得微球比表面积越大,对苯酚的吸附量越高。  相似文献   

2.
沥青基球状活性炭对几种生理分子的吸附性能   总被引:6,自引:1,他引:6  
考察了具有不同BET比表面积及不同孔结构的沥青基球状活性炭(PSAC)对溶液中尿毒症分子肌酐、有益分子α-淀粉酶和脂肪酶的吸附行为,测定了PSAC对肌酐的吸附等温线及吸附速度曲线,并根据Freundlich等温线方程对肌酐吸附等温线数据进行处理,检验了实验数据与方程的吻合度,确定了方程参数。结果表明:PSAC对α-淀粉酶及脂肪酶吸附选择性差,对肌酐的吸附选择性好。PSAC对肌酐分子的吸附平衡容量取决于溶液浓度、孔径和比表面积;吸附速率随孔径增大而增加。PSAC对α-淀粉酶及脂肪酶的吸附选择性取决于PSAC的孔结构,孔越大吸附选择性越好。因此,评价PSAC吸附性能时需要考虑比表面积、孔结构及吸附质分子的特性。  相似文献   

3.
采用悬浮聚合法制备了前体树脂聚对位二乙烯苯(PPDVB),进一步通过悬挂双键后交联反应合成了后交联树脂(PPDVBpc),测试了PPDVBpc对水中苯酚的吸附性能。结果表明:后交联后,PPDVBpc的比表面积和孔容显著增加,BET比表面积高达1483.1m2/g。树脂对苯酚的吸附动力学符合准一级和准二级动力学方程,吸附等温线可用Freundlich模型拟合,柱吸附实验说明后交联树脂可以完全吸附水溶液中的苯酚,9BV工业乙醇可完全再生树脂。  相似文献   

4.
将中草药药渣微波干燥后经碳化、KOH活化制备出具有较高比表面积的多孔炭质材料。采用比表面积及孔隙分析仪测定其N_2吸附脱附等温线;采用扫描电子显微镜、X射线衍射分析仪对介孔材料表面显微结构、及物相变化进行了表征,并分析了多孔炭材料对苯酚的吸附性能。研究结果表明,当炭碱质量比1∶4时,制备的改性多孔炭材料具有丰富的多孔结构,其比表面积达2079.25m~2,介孔率达到79.10%;多孔炭材料对苯酚的饱和吸附量达到187.5mg/g。苯酚在多孔炭材料上的吸附行为符合Langmuir吸附模型。  相似文献   

5.
活性竹炭对苯酚的吸附动力学   总被引:13,自引:0,他引:13  
研究了30℃下活性竹炭对苯酚溶液的吸附动力学,考察了苯酚初始浓度和吸附剂粒径的影响,并用三种动力学模型进行了拟合.结果表明:活性竹炭对苯酚的吸附动力学过程可以用准二级模型进行很好的描述,拟合所得的初始吸附速率随着苯酚浓度的增加和竹炭粒径的减小而提高.颗粒内扩散模型分析表明,活性竹炭对苯酚溶液的吸附过程中,颗粒内扩散为主要速率控制步骤.  相似文献   

6.
竹炭对铬(Ⅵ)离子吸附性能的研究   总被引:1,自引:0,他引:1  
研究了竹炭的粒径与用量,以及溶液的pH值与初始浓度、吸附时间、温度等因素对Cr(Ⅵ)离子吸附性能的影响.结果表明,竹炭对Cr(Ⅵ)离子的吸附能力随其粒径的增大而降低;在酸性条件下,尤其是当pH值<3时,竹炭能够很好地适应Cr(Ⅵ)离子初始浓度的变化,120min内达到吸附平衡,对其有较好的去除率;按Cr(Ⅵ)/竹炭质量比为1∶1200投加竹炭,Cr(Ⅵ)离子的去除率可达到87.8%以上;竹炭对Cr(Ⅵ)离子等温吸附服从Freundlich方程式,在低于20℃的较低温度下容易进行,吸附效果更好.竹炭可作为理想的除铬吸附材料.  相似文献   

7.
采用阳极弧放电等离子体方法制备了高纯银纳米粉末.利用X射线衍射(XRD)、透射电子显微镜(TEM)对样品的形貌、晶体结构、粒度进行性能表征.利用静态表面吸附仪依据BET多层吸附原理,在液氮温度下(78K)和气体饱和蒸气压力范围内测试样品对N2的吸附-脱附等温线,用图解法根据吸附等温线求出单层吸附容量,由BET吸附公式计算出纳米粉末比表面积.结果表明:银纳米粉末的晶体结构为fcc结构,粒径范围在10~50nm,平均粒径为26nm,比表面积为23.81 m2/g.  相似文献   

8.
以速生杉木为原料,经过苯酚液化物后加入六次甲基四胺熔融纺丝,初纺纤维固化处理后直接炭化制备出碳纤维,并对碳纤维的比表面积、孔径分布以及吸附特性进行了研究。研究结果表明,木材液化物碳纤维样品的等温线属于典型的Ⅰ型吸附等温线,其吸附滞后回线属于H4型。木材液化物碳纤维孔径主要以微孔为主,微孔率达到73.4%。碳纤维样品的BET比表面积、微孔面积、微孔容随着炭化温度的提高呈增大趋势,其中600~800℃是其孔隙结构发生变化的关键温度区间。液化原料中木材/苯酚比对其制备的碳纤维的比表面积、孔容及孔径的影响变化不大。  相似文献   

9.
镍纳米粉的比表面积和孔结构研究   总被引:3,自引:0,他引:3  
采用阳极弧放电等离子体方法制备了高纯镍纳米粉,利用X射线衍射(XBD)、透射电子显微镜(TEM)对粉末的形貌、晶体结构、粒度进行了表征。样品的N_2的吸附-脱附等温线采用静态表面吸附仪在液氮温度下(78 K)在气体饱和蒸气压力范围内测试。依据BJH理论模型计算探讨了样品的累积孔表面积、累积孔体积、孔径及其BJH脱附分布等性能。用图解法由等温吸附直线求出单层吸附量,利用BET吸附公式计算出样品的比表面积。结果表明,镍纳米粉的比表面积为14.23 m~2/g,粒径为46 nm。  相似文献   

10.
通过辐射接枝的方法在聚丙烯(PP)纤维上接枝丙烯酸单体,涂覆硅酸钠后经氯化钙交联得到接枝硅酸钙的PP功能化纤维(PP-g-CaSiO3)。红外光谱(IR)和扫描电镜图(SEM)表明硅酸钙成功地接枝到PP纤维表面。BET测试表明,当接枝率为46%时,PP-g-CaSiO3的比表面积高达376.64m2/g。PP-g-CaSiO3对水中双酚A(BPA)表现出良好的吸附性能,饱和吸附量达到39.23mg/g,吸附等温线满足Langmuir模型,吸附动力学符合二级动力学模型。  相似文献   

11.
12.
According to iodine number, amount of methylene blue adsorption, the BET specific surface area, and the yield, the conditions for preparing activated carbons as adsorbents from plum kernels were optimized. The activation temperature and time tested were in the ranges 750-900 degrees C and 1-4 h, respectively. Adsorption isotherms of two commercial dyes and phenol from water on such activated carbons were measured at 30 degrees C. It was shown that the optimal activation temperature and time depended on the molar mass of the solutes, and all equilibrium isotherms could be fitted by the Langmuir equation. The experimental results indicated that the prepared activated carbons were economically promising for adsorption removal of dyes and phenol, in contrast to other commercial adsorbents.  相似文献   

13.
The adsorption of dimethyl sulfide from an aqueous solution by a cost-effective bamboo charcoal from Dendrocalamus was studied in comparison with other carbon adsorbents. The bamboo charcoal exhibited superior adsorption on dimethyl sulfide compared with powdered activated carbons at different adsorbent dosages. The adsorption characteristics of dimethyl sulfide onto bamboo charcoal were investigated under varying experimental conditions such as particle size, contact time, initial concentration and adsorbent dosage. The dimethyl sulfide removal was enhanced from 31 to 63% as the particle size was decreased from 24-40 to >300 mesh for the bamboo charcoal. The removal efficiency increased with increasing the adsorbent dosage from 0.5 to 10mg, and reached 70% removal efficiency at 10mg adsorbed. The adsorption capacity (μg/g) increased with increasing concentration of dimethyl sulfide while the removal efficiency decreased. The adsorption process conforms well to a pseudo-second-order kinetics model. The adsorption of dimethyl sulfide is more appropriately described by the Freundlich isotherm (R(2), 0.9926) than by the Langmuir isotherm (R(2), 0.8685). Bamboo charcoal was characterized by various analytical methods to understand the adsorption mechanism. Bamboo charcoal is abundant in acidic and alcohol functional groups normally not observed in PAC. A distinct difference is that the superior mineral composition of Fe (0.4 wt%) and Mn (0.6 wt%) was detected in bamboo charcoal-elements not found in PAC. Acidic functional group and specific adsorption sites would be responsible for the strong adsorption of dimethyl sulfide onto bamboo charcoal of Dendrocalamus origin.  相似文献   

14.
Wu Y  Li Z  Xi H 《Journal of hazardous materials》2004,113(1-3):131-135
In this work, the effects of the microporosity and chemical surface of polymeric adsorbents on adsorptive properties of phenol were investigated. Textural parameters of four kinds of polymeric resins, namely AB-8, D4006, NKA-II and D16 resin, were separately measured by ASAP 2010. The surface chemistry of these polymeric resins was determined by means of inverse gas chromatography (IGC) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Static equilibrium adsorption experiments were carried out to obtain the isotherms of phenol on the polymeric resins. It was shown that NKA-II and AB-8 resin possessed relatively high BET surface areas and micropore volumes, while D4006 and D16 resin possessed comparatively low BET surface areas and micropore volumes. The results of IGC experiments revealed that NKA-II resin had extraordinary high specific component of the free energy of adsorption both for polar acetone and benzene probe, and thus extraordinary strong surface polarity compared to the other polymeric resins. It was also found that the isotherm of phenol on NKA-II was much higher than that on the other polymeric resins due to its strongest surface polarity and largest micropore volume among four kinds of resins. These experimental observations indicated that adsorption of phenol on the polymeric resins depended greatly on their microporosity and surface chemistry. The well-developed microporosity and the strong surface polarity would improve the adsorption of phenol on the polymeric resins.  相似文献   

15.
Adsorption of industrially important dyes namely bromophenol blue, alizarine red-S, methyl blue, methylene blue, eriochrome black-T, malachite green, phenol red and methyl violet from aqueous media on activated charcoal has been investigated. The effect of shaking time, pH and temperature on the adsorption behaviour of these dyes has been studied. It was noted that adsorption of all the dyes on activated charcoal decreases with an increase in the pH and the temperature. The adsorption isotherms at different temperatures were found to be of L-type. Adsorption data was fitted to Freundlich, BET and Langmuir isotherms and various adsorption parameters have been calculated. The thermodynamic parameters such as DeltaG, DeltaH and DeltaS were calculated from the slopes and intercepts of the linear variation of lnK against 1/T, where K is the adsorption coefficient obtained from Langmuir equation, was used. The calculated values for the heat of adsorption and the free energy indicate that adsorption of dyes is favored at low temperatures and the dyes are chemisorbed on activated charcoal.  相似文献   

16.
A series of experiments are described which identify those characteristics of charcoals which are important for gunpowder manufacture. Charcoals from Alder Buckthorn, Alder, Beech and Douglas Fir woods were prepared by carbonization under nitrogen in the heat-treatment temperature range 523 to 1173 K. The charcoals were characterized by elemental analysis, differential thermal analysis, measurement of spontaneous ignition temperature, morphology using scanning electron microscopy, surface-area assessment using carbon dioxide as adsorbate, mercury porosimetry and microstrength analyses. Results indicate that for charcoals with acceptable carbon contents of 70 to 80 wt %, extremely fine control of carbonization conditions is required. The surface area and carbon content of the charcoal increased rapidly on heat treatment. The surface area of the charcoal reached values of –400 m2 g–1. Mercury porosimetry indicated that Alder Buckthorn and Douglas Fir charcoals had cumulative pore volumes greater than Alder charcoal and substantially greater than Beech charcoal. The Beech charcoal was the most friable of the three hardwood charcoals tested using microstrength analysis. Alder Buckthorn and Alder charcoals are recommended for gunpowder manufacture.  相似文献   

17.
竹炭对甲基橙溶液吸附行为的研究   总被引:1,自引:0,他引:1  
探索了竹炭对甲基橙溶液的吸附行为,测定了竹炭的粒径与投料量以及溶液的pH值与浓度、吸附时间、温度等因素对甲基橙吸附性能的影响.结果表明,竹炭对甲基橙的吸附能力随其粒径的增大而降低,甲基橙溶液pH值在2~4酸度范围时,竹炭对甲基橙有较好的吸附能力,达到最佳吸附效果时溶液的pH值为2.吸附质浓度增加,竹炭对其吸附率减小,随着投料量的增加,吸附率不断提高.竹炭对甲基橙的等温吸附服从Freundlich方程式.竹炭对甲基橙的吸附可在100min内达到平衡,最佳吸附温度为60℃.通过对这些参数的探索和测定,竹炭对甲基橙的吸附率可达到90%以上,能有效除去溶液中的甲基橙.  相似文献   

18.
19.
KOH活化法高比表面积竹质活性炭的制备与表征   总被引:7,自引:0,他引:7  
以竹屑为原料,研究了KOH活化法高比表面积活性炭的制备工艺.分别考察了浸渍比、活化温度、活化时间等工艺参数对产品吸附性能的影响,并提出了可能的活化机理.在所研究的实验条件下,最佳的制备工艺是浸渍比1.0,活化温度800℃,活化时间2h.所得到的活性炭产品的比表面积和孔容可达2996m2/g和1.64cm3/g.该产品附加值高,在吸附领域特别是在双电层电容器的电极材料领域有广阔的应用前景.  相似文献   

20.
采用特殊烧制工艺制得的优质竹炭,比表面积高达700m2/g .将竹炭制成0.5~100μm的超细微粉,与多种高分子材料结合,可制成许多种高分子复合材料,如各种具有不同性能、不同用途和不同类型的包装材料-炭布,这些炭布具有极好的催化活化、吸附分解、吸湿干燥和除臭抗菌等性能.  相似文献   

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