碳酸乙烯酯和碳酸丙烯酯复合溶剂的工业脱碳性能研究

在碳酸乙烯酯（乙碳）和碳酸丙烯酯（丙碳）复合溶剂脱除合成气ＣＯ２中试实验的基础上,就乙碳和丙碳的分子结构特点对乙碳和丙碳及两者复合溶剂的ＣＯ２吸收性能进行了比较,讨论了乙碳－两碳－水复合溶剂的相行为及其对工业操作的影响,并验证了乙碳－丙碳复合溶剂应用于工业的可行性及其特点。     

CO_2在碳酸丙烯酯和胺、水混合溶剂中的溶解度

近年来,为解决碳酸丙烯酯（Propylene Carbonate简称丙碳）脱除 C风工艺中出现 的脱碳净化度低、溶剂循环量大、设备腐蚀严重等问题而相继开发了多种改型丙碳复合溶 剂,其中作者等人研制的由丙碳和适量的叔胺（MDEA）、水构成的混合溶剂,不仅脱碳 性能明显优于丙碳,而且有效地解决了设备腐蚀问题。本文研究了CO。在此混合溶剂中 的溶解度与温度和压力的关系。     

碳酸丙烯酯脱碳装置技术改造小结

在碳丙脱碳装置中增加了贫液氨冷器 ,改造了碳丙泵 ,增设了变换气氨冷器 ,从而提高了碳丙脱碳装置的吸收和再生效果     

碳酸丙烯酯复合溶剂研究

对碳酸丙烯酯复合溶剂脱碳进行了研究,开发出新型的复合溶剂：碳酸丙烯酯十二乙氨基乙醇。这种复合溶剂吸收二氧化碳的能力是纯碳酸丙烯酯的１．７２倍。实验选出其中两种最佳配比的复合溶剂进行动力学研究,获得其传质系数关联式,并考察了流体力学和温度对传质系数ＫＬ的影响。     

丙碳脱碳应用中的问题及改进

碳酸丙烯酯脱除CO2（下称丙碳脱碳）这一技术开发成功至今，大部份从碳铵改产尿素或为磷铵配套的小合成氨厂都有杉了在1.6MPa左右吸收压力下的丙烯脱碳这一工艺流程，其最大特点是工艺流程较简单，操作方便，节电，溶剂再生时不需用蒸汽加热，这点对热比较紧张的小氮肥厂来说是具有很大吸引力的。     

碳丙脱碳小改小革

碳丙脱碳小改小革（湖北省浠水氮肥厂４３６２００）在碳铵改产尿素的技术路线中，碳酸丙烯脂（简称碳丙）脱碳被广泛应用：由于生产线置和控制要求不尽相同，脱碳效果有较大差异．我厂系小碳铵改产小尿素厂家之一，碳丙脱碳装置２．７ＭＰａ系化工部第四设计院设计，该装...     

碳酸丙烯酯稀溶液饱和蒸汽压的测定

本文实验测定丙碳稀溶液饱和蒸汽压数据，用数学回归方法建立了浓度－温度－饱和蒸汽压三者关联式，为丙碳脱碳溶剂损耗等工艺提供更简便的计算式。     

降低吸收温度提高碳丙脱碳装置能力

某厂年产8万吨合成氨装置通过改造,扩大到11万吨,碳酸丙烯脂脱碳系统(简称碳丙)为适应合成氨能力增加的要求,也需进行改造。有两种方案可供选择,一种方案是按原设计吸收操作条件,扩建脱碳设备;另一种方案是充分利用原设计碳丙脱碳装置,根据碳丙脱碳的物理吸收特性,增加单位碳丙液溶解 CO_2量。第一种方案仿效原设计,增加吸收塔等设备,投资多一些,技术     

小合成氨碳丙脱碳系统的清洗

我国采用碳酸丙烯脂脱除变换气中二氧化碳的小合成氨装置中,脱碳系统的主要设备内极易沉积硫垢,这种结垢是由碳丙工艺所决定,因而不可避免．硫垢影响设备的运行,但由于硫垢与水垢性能相差极大,通常的机械清洗与化学清洗很难奏效．通过５ 套小合成氨碳丙脱碳设备的清洗证明：ＨＦ－ ００２ 络合清洗法是这类硫垢的有效清除方法．     

合成氨工艺脱碳方法评述

介绍了4种脱碳方法的发展现状,并对其性能优劣进行评述:碳酸丙烯酯(PC)法不仅溶剂损失大,净化气中CO2含量高,而且碳丙溶液对碳钢有腐蚀,生产效率低,能耗高;N-甲基二乙醇胺(MDEA)法溶液损耗小,净化度高,且对设备无腐蚀;聚乙二醇二甲醚(NHD)法不仅溶剂损耗低,净化度高,而且对设备腐蚀极小,能耗低,工艺流程简单,投资低。低温甲醇洗法工艺流程复杂,设备较多,投资高,但运行成本较低,而且溶液具有较好的热稳定性和化学稳定性,吸收选择性好,净化度高。脱碳方法的评述将会对合成氨工业生产中脱碳方法的选取起到一定的参考启示作用。     

Octahedral Chloride Complexes of Trivalent Actinides and Lanthanides in Solution

The preparation of the crystalline octahedral complex tris (triphenylphosphonium) hexachloro-americate (III) is reported. The absorption spectra of the octahedral hexachloro complexes of curium (III), americium (III) and most of the trivalent lanthanides in a nitrile solvent are also reported. The dissociation of the hexachloro americate complex anion in the nitrile solvent and in propylene carbonate has been examined. The stepwise association constant K₆ for its formation from the pentachloro complex was found to be 150 ± 20 and 60 ± 20 in 85% vol succinonitrile 15% acetonitrile solvent and in propylene carbonate respectively.     

Modified Zinc Oxide for the Direct Synthesis of Propylene Carbonate from Propylene Glycol and Carbon dioxide

A series of modified zinc oxide catalysts were prepared and their catalytic activities were evaluated by the direct synthesis of propylene carbonate from propylene glycol and carbon dioxide in the presence of acetonitrile, which acted as not only the solvent but also the dehydrating reagent in the reaction. The reusability test indicated that the modified catalysts had the high stability. Ammonium carbonate was added into the reaction to significantly elevate the selectivity of propylene carbonate.     

Absorption of carbon dioxide into non-aqueous solutions ofN-methyldiethanolamine

The chemical absorption rate of carbon dioxide was measured in non-aqueous solvents, which dissolved N-methyldiethanoamine (MDEA), such as methanol, ethanol, n-propanol, n-butanol, ethylene glycol, propylene glycol, and propylene carbonate, and water at 298 K and 101.3 kPa using a semi-batch stirred tank with a plane gas-liquid interface. The overall reaction rate constant obtained from the measured rate of absorption of carbon dioxide under the condition of fast pseudo-first-order reaction regime was used to get the apparent reaction rate constant, which yields the second-order reaction rate constant and the reaction order of the overall reaction. There was approximately linear dependence of the logarithm of the rate constant for the overall second-order reaction on the solubility parameter of the solvent. In non-aqueous solutions of (MDEA), dissolved carbon dioxide is expected to react with solvated (MDEA) to produce an ion pair.     

Measurement of transference numbers for lithium ion electrolytes via four different methods, a comparative study

We report here on comparative measurements of cationic transference numbers of some lithium battery related electrolytes including lithium tetrafluoroborate in propylene carbonate, lithium hexafluorophosphate in blends of ethylene carbonate/diethyl carbonate and ethylene carbonate/propylene carbonate/dimethyl carbonate, as well as lithium difluoromono (oxalate) borate in an ethylene carbonate/diethyl carbonate blend via four different methods. Whereas three electrochemical methods yield transference numbers decreasing with concentration in accordance with electrostatic theories, valid for low to intermediate concentrations of the electrolyte, nuclear magnetic resonance spectroscopy measurements show increasing transference numbers with increasing concentration. The discrepancy is attributed to effects of ion–ion and ion–solvent interaction.     

ZnTe electrodeposition from organic solvents

The electrodeposition of zinc telluride was investigated from various organic solvent baths such as methanol, acetonitrile, propylene carbonate. The potential window increases with increasing boiling point of the solvents. In particular, ZnTe with high crystallinity could be obtained in propylene carbonate by the under-potential deposition (UPD) of Zn. The current efficiency for ZnTe deposition in propylene carbonate was enhanced considerably compared to that in acidic aqueous solutions. A single-phase ZnTe film close to the ideal stoichiometric composition of ZnTe could be obtained at 423 K and −0.8 V versus Ag/AgCl in propylene carbonate with a molar ratio of Zn(II)/Te(IV) = 10 and a low Te(IV) concentration; the film had a smooth and dense granular crystal morphology.     

Efficient propylene carbonate synthesis from propylene glycol and carbon dioxide via organic bases

Organic bases were first used as effective catalysts for the synthesis of propylene carbonate from propylene glycol and carbon dioxide in the presence of acetonitrile. Acetonitrile in the reaction acted as not only the solvent but also the dehydrating reagent to remove the water produced from the reaction. It was interesting that upon ammonium carbonate being introduced into the reaction system, the catalytic selectivity was significantly enhanced. With 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as the catalyst, the yield of propylene carbonate could reach 15.3% with the selectivity of 100% under the optimal conditions.     

电池级碳酸酯类溶剂的一种提纯方法

研究了一种吸附与蒸馏相结合的提纯锂离子电池用碳酸酯类溶剂的方法,研究结果表明在蒸馏时加入金属钠可以有效减少含质子氢杂质,还对提纯原理进行了分析。