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11.
简要介绍淮化集团浓硝酸生产工艺,通过对热发烟硝酸生产的关键设备高压釜的进料管,筛板的改造,增加氧气压力,提高N2O4纯度等工艺调整,使高压釜的生产能力由原设计的12.8t热酸/h增加到38.6t热酸/h。 相似文献
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13.
高温浓硫酸用XDS不锈钢板材的研究 总被引:1,自引:0,他引:1
根据合金设计的理论,对高温浓硫酸用不锈钢进行全面的改性研究,进而开发出新型耐高温浓硫酸用不锈钢板材XDS。比较并论述了XDS不锈钢在高温浓硫酸中的力学性能和耐腐蚀性能,认为XDS不锈钢已达到国际先进水平,为制造硫酸厂的干吸塔、酸泵等设备提供了优异的钢材,也为低温热回收系统的应用创造了条件。 相似文献
14.
J. F. Toro-Vazquez Alejandro Rocha-Uribe 《Journal of the American Oil Chemists' Society》1993,70(6):589-594
The adsorption of peroxides, unsaturated carbonyls, free fatty acids and carotenoids from unrefined sesame oil on vegetable
carbon (5%, w/w) in a miscella system was studied. Three different solvent conditions (hexane/ethanol, 100:0, 95:5 and 75:25,
vol/vol), combined in a factorial design with five levels of solvent (0, 10, 20, 30 and 40%, w/w), were used to develop the
miscella. Equilibrium adsorption was not achieved during the 100 min of adsorption, mainly because the oil components were
involved in oxidation reactions during the adsorption process. However, for a given solvent concentration, adsorption of the
oil components showed a significant linear regression on their respective initial concentration in the miscella (Ci). Peroxides and carbonyls showed, at all solvent levels investigated, an affinity for the carbon more independent of their
Ci than free fatty acids and carotenoids. In general, at the same Ci, a higher adsorption was achieved as solvent concentration increased. The results indicated that free fatty acid adsorption
may depend on competitive adsorption based on molecule hydrophobicity. However, in spite of the higher hydrophobicity of carotenoids,
compared with free fatty acids, they might not be competing for the same adsorbing sites. Ethanol showed a prooxidant effect
that increased peroxide production during adsorption but did not affect the reaction involved in carbonyl production. 相似文献
15.
用工业废碱水处理反渗透法高含盐排放浓水 总被引:2,自引:0,他引:2
反渗透处理装置排放的浓水含盐量很高,如果不经处理直接排放势必对周围环境造成污染和水的浪费,氧化铝生产工艺废水中含有大量的碳酸钠、苛性碱等碱类物质,pH值达到13左右,回水量约2000m^3/h,用这些废水和反渗透浓水混合进行软化处理,降低浓水中的钙镁离子含量,并对难去除的硫酸盐进行稀释降低浓度,回用到蒸发循环水系统作为补充用水、氧化铝生产部分工艺用水、设备冷却用水,达到浓水回收再利用的目的。该方案实施后效果十分显著,回收反渗透浓水约60m^3/h,减少污水系统补充新水,降低生产用水费用约每年176万元。 相似文献
16.
17.
Concentrated inverse emulsion polymerization was used for making chromatography columns (based on crosslinked polystyrene divinylbenzene (PS‐DVB)) with pore sizes less than 10 μm. According to DSC‐thermal gravimetry thermograms, it was confirmed that the residual monomer concentration after polymerization process is negligible. For application of these columns in chiral chromatography, the β‐cyclodextrin is chemically fixed on the PS‐DVB resin pore surface. The presence of hydroxyl groups in the PS‐DVB resin after chemical modification was confirmed by FTIR spectroscopy. By chemical modification of the PS‐DVB resin, thermal stability increased up to 446°C. The structure of columns was analyzed by scanning electron microscopy (SEM). SEM evaluations showed that the porous structure of PS‐DVB resin was maintained intact after the chemical modification with β‐cyclodextrin. According to X‐ray data, presence of the crystalline domain that is related to β‐cyclodextrin is confirmed.© 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 857–863, 2006 相似文献
18.
从生产实践出发,探讨了33dtex/24f双细全牵伸丝(FDY)丝的生产工艺。在选择工艺参数时应考虑色母粒对纺丝生产的影响。合理地选择纺丝温度、喷丝板孔径、拉伸速度、牵伸倍数可稳定地生产性能良好的FDY丝。 相似文献
19.
Y. Nakama Y. Shiojima Y. Takeshita M. Yamaguchi 《Journal of the American Oil Chemists' Society》1997,74(7):803-808
The formation of a complex, composed of lauroamphoglycinate (LG), oleic acid (OA) and water, was investigated, and this system
was applied to emulsification. The complex was formed in the water-rich area (more than 90% in this system) at a molar ratio
of OA to LG from 1 to 3, where two-phase systems of water and the complex existed. The interaction between LG and OA, both
in the aqueous solution and at the interface of liquid paraffin dissolving the OA and LG solution, was studied by pH measurements
and interfacial tension measurements, respectively. The results implied that LG and OA were linked stoichiometrically, both
in aqueous solution and at the interface, and formed complexes. X-ray diffraction patterns and the strong hydrophobicity showed
that the equimolar complex composed of LG, OA, and water was a liquid crystal with a reversed hexagonal structure. The reversed
hexagonal liquid crystal was capable of solubilizing a certain amount of liquid paraffin in its alkyl group parts while maintaining
its hexagonal structure. These results suggest the possibility to prepare a W/O-type emulsion by using the liquid crystal
formed by LG, OA, partial liquid paraffin, and water as the continuous phase. The authors could obtain a stable W/O emulsion
without coalescence of the water droplets that contained a substantial amount of water (approximately 90%). Furthermore, various
types of emulsions, O/W, W/O, W/O/W, could be prepared by changing the ratio of LG and OA. 相似文献
20.
A novel polymerization procedure, the concentrated‐emulsion graft polymerization of styrene monomer with poly(butyl acrylate) seed, was proposed for the production of a self‐compatibility macromolecule alloy. The effects of the butyl acrylate content, sodium dodecyl sulfate concentration, and polymerization temperature on the graft ratio were investigated. Scanning electron microscopy, transmission electron microscopy, and impact strength were used to characterize the microstructure and mechanical performance of the self‐compatibility macromolecule alloy. The results showed that increasing the butyl acrylate content, reducing the sodium dodecyl sulfate concentration, and improving the polymerization temperature all favored an increased graft ratio, which resulted in increased impact strength of the self‐compatibility macromolecule alloy. Therefore, the concentrated‐emulsion polymerization method is particularly suitable for seed‐graft polymerization. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2915–2920, 2002; DOI 10.1002/app.10288 相似文献