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21.
凹凸棒石基吸附剂的制备及改性 总被引:1,自引:0,他引:1
探讨了甘肃产凹凸棒石与活性氧化铝复配所制吸附剂的吸附性能,考察了原料配比、焙烧温度对该吸附剂吸附性能的影响,以及吸附剂改性后的吸附性能。根据试验结果,初步确定了吸附剂的原料配方,其中凹凸棒石占总质量的55%-70%,活性氧化铝占总质量的25%~40%。研究发现,在此配比及焙烧温度为600—700℃时.该吸附剂具有高吸附性;采用浓度为1.0mol/L的硫酸改性1.0h可使吸附剂具有较高的吸附容量。 相似文献
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分别通过浸渍法和焙烧法制备了两种复合吸附剂氯化钙/硅胶和氯化钙/凹凸棒土。在温度40℃、相对湿度20%条件,氯化钙/硅胶复合吸附剂的吸水性能随样本中氯化钙含量的增加而增加。氯化钙/凹凸棒土的最佳焙烧条件为焙烧温度300℃,焙烧时间2 h。在相对湿度为20%,吸附时间分别为15,20 min时,氯化钙/凹凸棒土的SCP分别为140.26,128.92 W/kg,远大于同等条件下氯化钙/硅胶的SCP。两种吸附剂的吸附性能对比表明,氯化钙/凹凸棒土吸附剂由于其良好的吸水性能更加适用于低温驱动的吸附制冷机。 相似文献
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A series of pH‐sensitive composite hydrogel beads, carboxymethyl cellulose‐g‐poly(acrylic acid)/attapulgite/sodium alginate (CMC‐g‐PAA/APT/SA), were prepared by combining CMC‐g‐PAA/APT composite and SA, using Ca2+ as the ionic crosslinking agent and diclofenac sodium (DS) as the model drug. The effects of APT content and external pH on the swelling properties and release behaviors of DS from the composite hydrogel beads were investigated. The results showed that the composite hydrogel beads exhibited good pH‐sensitivity. Introducing 20% APT into CMC‐g‐PAA hydrogel could change the surface structure of the composite hydrogel beads, decrease the swelling ability, and relieve the burst release effect of DS. The drug cumulative release ratio of DS from the hydrogel beads in simulated gastric fluid was only 3.71% within 3 hour, but in simulated intestinal fluid about 50% for 3 hour, 85% for 12 hour, up to 90% after 24 hour. The obtained results indicated that the CMC‐g‐PAA/APT/SA hydrogel beads could be applied to the drug delivery system as drug carriers in the intestinal tract. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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以凹凸棒分散液为吸附剂, Fe2+/ATP为复合催化剂对印染废水中的阳离子红X-GRL进行处理实验。主要分析了Fe2+负载时间、反应温度和Fe2+溶液浓度对吸附性能的影响以及影响凹凸棒土联用Feton法与阳离子红反应的因数。实验结果显示,制备ATP/Fe2+的合适的条件为:凹凸棒土煅烧温度为400℃;负载铁时间为5 h;负载铁浓度为1500 mg/L;负载温度为80℃。 相似文献
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A novel superabsorbent composite, polyacrylamide/attapulgite, from acrylamide (AM) and attapulgite (APT), was prepared by free‐radical polymerization, using N,N′‐methylenebisacrylamide (MBA) as a crosslinker and ammonium persulfate (APS) as an initiator. The effects of hydrochloric acid (HCl) concentration, acidification time, and acidification temperature while acidifying APT and temperature and APT heat‐activation on water absorbency of the superabsorbent composite in distilled water and in 0.9 wt % NaCl solution were studied. The water absorbency first decreases with increasing the HCl concentration while acidifying APT, and then increases with further increasing the HCl concentration. Prolongation of acidification time is of benefit to the increase of water absorbency. At a given HCl concentration, water absorbency for the composite increases with increasing acidification temperature. An important increase in water absorbency was observed after incorporating heat‐activated APT into the polymeric network, reaching a maximum of 1964 g g?1 with the APT heat‐activated at 400°C. Acid‐ and heat‐activation can influence chemical composition, crystalline structure, cation exchange capacity (CEC), and specific surface area of APT according XRF, XRD, FTIR analysis, and physicochemical properties test, and then on water absorbency of corresponding PAM/APT superabsorbent composite. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2419–2424, 2007 相似文献
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Summary: A solid lubricant composite material was prepared by compression molding PTFE and acid treated nano‐attapulgite. The friction and wear tests were performed on a block‐on‐ring wear tester. Scanning electron microscopy (SEM), energy‐dispersive X‐ray spectrometer (EDS) and DSC were utilized to investigate material microstructures and examine modes of failure. Experimental results showed that there was no significant change in coefficient of friction, but the wear rate of the PTFE composite was orders of magnitude less than that of pure PTFE. Acid treated nano‐attapulgite was superior to untreated nano‐attapulgite in enhancing the wear resistance of PTFE. Moreover, the wear resistance of the composite increased monotonically with increasing treated attapulgite concentration. Investigation of transfer film and analysis of debris for PTFE and its composite showed that acid treated nano‐attapulgite filled to PTFE could facilitate formation of transfer film on the steel ring surface and inhibit breakage of PTFE molecular chain. The PTFE composite with higher heat absorption capacity exhibited improved wear resistance. Furthermore, the steel ring counterface abrasion was not found.
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