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1.
P. M. Solozhenkin E. A. Deliyanni V. N. Bakoyannakis A. I. Zouboulis K. A. Matis 《Journal of Mining Science》2003,39(3):287-296
The original method is developed for producing the new inorganic sorption material of akaganeite bgr-FeO(OH). The material in question is characterized relative to arsenic contained in aqua. The possibility is established for removing arsenate ions from water by contemporary physicochemical methods. 相似文献
2.
复合吸附剂提高催化裂化柴油安定性的研究 总被引:7,自引:1,他引:6
用改性活性白土吸附精制催化裂化柴油,精制后柴油的安定性得到显著提高。对精制后柴油的分析表明:复合吸附剂能够大幅降低油品中的总硫和碱性氮含量,对油品其它性质无大的影响。 相似文献
3.
重油催化裂化干气氢提纯技术的开发 总被引:3,自引:0,他引:3
石家庄炼油厂和西南化工研究设计院合作开发的中国石化系统第一套利用变压吸附技术进行RFCC干气氢提纯工业试生产装置一年的平稳运行说明:提纯后产品氢纯度达99.9%,回收率大于85%;操作简便灵活;装置负荷弹性裕度大;经济效益显著。实践证明它是一项富有吸引力的新工艺,为重油催化裂化装置的挖潜增效展示了美好的前景。 相似文献
4.
膨润土在废水处理中的应用综述 总被引:16,自引:2,他引:14
随着环境保护标准的日益严格,开发新型、廉价、高效的水处理材料也日趋紧迫。首先简要地介绍了非金属矿物材料——膨润土的矿物学特征。这些特征使得膨润土具有许多优良的基本特性,如电负性、离子交换性能等等。如果进一步针对膨润土的一种或者某些特性加以改性,膨润土就非常有可能在实际工程中被广泛应用。其次较为详细地综述了膨润土在废水处理中应用的现状,主要是作为制备吸附剂和絮凝剂的原料。而且,由膨润土改性所制成的吸附剂或絮凝剂对废水中的无机、有机污染物都有较为理想的去除率。最后,对膨润土的应用前景进行了展望。 相似文献
5.
To investigate the effects of multiple weak interactions on the binding of phenolic compounds by polymeric adsorbents, macroporous polystyrene (PS) resin and PS‐based adsorbents with different hydrogen‐bond acceptor atoms (PS CH2( OCH2CH2)n OCH3, n = 0, 1, 2, and 3, denoted as PS‐EG0, PS‐EG1, PS‐EG2, and PS‐EG3) were prepared. The phenol adsorption strength order on these adsorbents was PS/PS‐EG0 < PS‐EG1 < PS‐EG2 < PS‐EG3, indicating that the adsorption on PS and PS‐EG0 was driven by hydrophobic and π–π interactions, and the adsorption on PS‐EG1, PS‐EG2, and PS‐EG3 was driven by a hydrogen bond in addition to hydrophobic and π–π interactions. PS‐EG2 may adsorb a second phenol molecule on each binding site and PS‐EG3 may adsorb second and third ones. The adsorption strength of resorcinol increased in the order of PS, PS‐EG1, and PS‐EG2, indicating that the adsorption was driven by 0, 1, and 2 hydrogen bonds in addition to hydrophobic and π–π interactions. Similarly, the adsorption of phloroglucinol on PS, PS‐EG1, PS‐EG2, and PS‐EG3 was driven by 0, 1, 2, and 3 hydrogen bonds in addition to hydrophobic and π–π interactions because the adsorption strength increased in this order. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4652–4658, 2006 相似文献
6.
固体吸附式制冷系统中吸附剂一般是多孔介质结构,吸附剂的内部结构特征对传热特性和吸附质的传质特性有直接影响,进而影响吸附解吸时间。本文探讨利用分形理论来分析固体吸附剂的结构特点,为目前通过对吸附剂的固化处理来提高吸附剂的传热速率的处理方法提供理论上的分析,并指出最佳分形维数的分形结构。 相似文献
7.
吸附法脱除乙烯中少量氧气的吸附剂研究 总被引:7,自引:1,他引:6
采用重量法在电子天平上研究了C2H4和O2单组份在5A、13X、丝光沸石和碳分子筛等不同吸附剂上的吸附平衡性质和扩散动力学性质。结果表明,在沸石类吸附剂上,C2H4的平衡吸附量远大于O2的平衡吸附量,C2H4的吸附扩散速率也大于O2的扩散速率;在碳分子筛吸附剂上C2H4的平衡吸附量大于O2的平衡吸附量,但O2的吸附扩散速率远大于C2H4的扩散速率,其扩散系数是C2H4的239倍。单柱评价结果表明,C2H4-O2混合组份通过该碳分子筛吸附剂时,O2的破点时间长,C2H4的纯度可达100%。加压有利于选择吸附O2,而且加压吸附、常压脱附再生性能好。该碳分子筛是脱除高浓度乙烯中少量氧气的理想吸附剂。 相似文献
8.
ZhangXiaojing QinRuyi LiuJinlong 《中国炼油与石油化工》2003,(4):31-35
This article refers to the procedure for selection, evaluation and development of the LADS-D desorption agent associated with the LADS-A adsorbent used in the non-hydroprocessing adsorptive desulfurization (LADS) process for FCC naphtha developed by LPEC Refining Research Institute. The LADS-D desorption agent can effectively remove the sulfides adsorbed on the LADS-A adsorbent. The saturated LADS-A adsorbent can be instantly regenerated by the LADS-D desorption agent to recover its adsorption activity. The LADS-D desorption agent can not only effectively remove all impurities adsorbed on the adsorbent, but also has strong ability to dissolve the impurities to keep a stable desorption efficiency of adsorbent to be basically commensurate with fresh adsorbent after extended use. 相似文献
9.
Wenlong Zheng Xiao Chen Chunyang Liu Shiping Ren Li Zhang 《International Journal of Applied Ceramic Technology》2021,18(4):1244-1254
Silica-based ceramic cores are extensively used in investment casting process, during which they must exhibit sufficient flexural strength and deformation resistance. In this study, micro-sized mullite was used as an additive to silica-based ceramic cores to optimize their high temperature properties. To investigate the effects of micro-sized mullite on cristobalite crystallization, mechanical and thermal properties of silica-based ceramic cores, ceramic cores with different amounts of micro-sized mullite were fabricated. The XRD results showed that additional micro-sized mullite diminished the crystallization of cristobalite at high temperatures, primarily caused by the mullite related compressive stresses on the surface regions of fused silica particles. Three-point bending tests and SEM results showed that micro-sized mullite had a more significant effect on the flexural strength of ceramic cores compared with conventional additives. Particularly, the fracture mechanism of silica-based ceramic cores had been changed from intergranular fracture into a mixed fracture consisting of both intergranular and transgranular fracture. The mechanical and thermal properties of ceramic cores were all reduced slightly as the mullite content exceed 4.6 wt%. Hence, to optimize the properties of silica-based ceramic cores, the micro-sized mullite content should not exceed 4.6 wt%. 相似文献
10.
Wenxuan Pan Weidong Xuan Fangmiao Duan Xiaolong Bai Baojun Wang Zhongming Ren 《International Journal of Applied Ceramic Technology》2021,18(6):2284-2292
Mullite fibers composite silica-based ceramic cores were successfully prepared by injection molding. The effects of mullite fibers on the mechanical and thermal properties of ceramic cores were investigated. The results indicated that the linear shrinkage was significantly decreased and the porosity was gradually increased with the increase of mullite fibers. In addition, the flexural strength for the room temperature and the simulated casting temperature of 1500°C was increased to a maximum value when the content of mullite fibers was about 1 wt.%, and then decreased with the increase of mullite fibers. The mullite fibers of 1 wt.% presented excellent mechanical properties with a linear shrinkage of .65%, a porosity of 6.96%, and a flexural strength of 17 MPa at room temperature and 34.83 MPa at the simulated casting temperature of 1500°C. Besides, the change in microstructure and properties in various contents of mullite fibers were analyzed. 相似文献