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排序方式: 共有398条查询结果,搜索用时 15 毫秒
1.
氨氮监测采用预蒸馏处理后,比色测定结果明显偏低。在样品预蒸馏处理过程中,硼酸作为吸收液,使显色时溶液pH值偏低,导致显色不充分是其主要影响因素。通过采取增加显色剂加入量的方法,解决了显色pH值偏低的问题,得到满意的测定结果。 相似文献
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针对油品浑浊问题,经多方查找,确定系油品中含有表面活性剂及微量水所致,提出了采用通入干燥的压缩风或氮气吹扫的解决措施。 相似文献
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Decomposition of SRC-II middle distillate under surface vaporizing conditions was studied as a function of temperature (heating rate), vapour phase residence time and oxygen level. The stressed and unstressed fuel was analysed by capillary gas chromatography. Decomposition was found to be greatest at low temperature. Boiling mode did not appear to affect the extent of decomposition. Decomposition was weakly related to chemical class and strongly related to component volatility. The effect of gas phase residence time and oxygen level were negligible at the conditions studied. It is concluded that decomposition occurs primarily within the liquid and at the vaporizer surface. 相似文献
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介绍了中国石油辽阳石化分公司乙烯厂丙烯精馏塔塔底油-丙烷馏分油的精制工艺。该工艺可脱出丙烷馏分油中的绿油组分,从而提高了丙烷馏分油的使用效果和价值。 相似文献
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抚顺石油化工研究院研制开发的新一代FC -2 6高中油型加氢裂化催化剂 ,以W -Ni为加氢组分 ,以无定型硅铝为主载体 ,并添加改性分子筛。工艺研究及工业应用结果表明 ,FC -2 6催化剂活性及中油选择性高 ,稳定性好 ,原料适应性强 ,具有广阔的应用前景。 相似文献
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The recovery of squalene from deodorizer distillate derived from the physical refining of olive oil was evaluated by combining pressurized acidic esterification in a closed system with vacuum distillation. Esterification was carried out at 341, 359, 366, 391 and 395 K. The reaction at 395 K was found to be satisfactory as it decreased the acid value by 99.21% and generated a FAME concentration of 67.53% within 1 h. In order to demonstrate that the generation of FAME from deodorizer distillate was mainly due to the transformation of FFA, the reaction extent, which characterizes the reaction and simplifies calculations, was evaluated for FFA removal and the generation of FAME. Subsequent vacuum distillation allowed the separation of one fraction rich in FAME (94%), which can be used as a biofuel and accounted for 85% of the initial mass, and another fraction that was rich in squalene (78%) and may be used for manufacturing pharmaceutical products. The global squalene yield was 117 g kg−1 initial deodorizer distillate. 相似文献
9.
Bulin Boonrod Paweena Prapainainar Viganda Varabuntoonvit Kandis Sudsakorn Chaiwat Prapainainar 《International Journal of Hydrogen Energy》2021,46(17):10570-10585
Bio-hydrogenated diesel (BHD) is a second generation biofuel that can be produced from vegetable oil and hydrogen via hydroprocessing. BHD is considered as one of alternative and renewable energy. This work presents evaluation of environmental impacts of BHD produced from palm fatty acid distillate (PFAD) compared to fatty acid methyl ester (FAME). Greenhouse gas emission, energy consumption, and overall environmental impacts are assessed. System boundary is from palm oil cultivation to BHD production. The functional unit is defined as 1 kg of fuel produced at the plant. The results indicate that energy consumption of BHD-PFAD is 1.18 times higher than that of BHD-FAME, while giving GHG emission 13.56 times lower than that of BHD-FAME. The results of overall environmental impacts indicated that BHD-PFAD was 3.58 greater than that of BHD-FAME. 相似文献
10.
Alexandre Ruellan Violette Ducruet Audrey Gratia Lidia Saelices Jimenez Alain Guinault Cyrille Sollogoub Guillaume Chollet Sandra Domenek 《Polymer International》2016,65(6):683-690
Polylactide (PLA) is the most used biodegradable and biobased food packaging polymer for rigid containers and films. However, its low ductility is a hurdle for increasing its applications in flexible food packaging. A solution is the use of additives. Palm oil deodorizer distillate (PODC) is revealed to be an excellent additive promoting PLA ductility. PODC is a by‐product of vegetable oil refining, which is available in stable quality and in sufficient amounts. Amorphous PLA/PODC blends had an elongation at break of around 130% and that of semi‐crystalline blends was still around 55% compared to the initial 5% of neat PLA. At the same time the PLA rigidity and high glass transition temperatures were kept. PODC was also a very efficient processing aid, allowing for film blow extrusion. The blends were stable in properties during six months without exudation. They complied with legal norms of Food Contact Materials (EU 10/2011) and induced no sensorial alteration of packed food. Therefore PODC is a very interesting alternative to common plasticizers for the production of flexible PLA packaging films. © 2016 Society of Chemical Industry 相似文献