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1.
从合成气制取液体燃料的浆态床FT合成/固定床2SM-5改质的反应系统由Ⅰ段鼓泡浆液反应器(内径40mm,高450Omm)和Ⅱ段固定床ZSM-5反应器(内径40mm,高900mm)组成,在温度250~280℃(Ⅰ段),300~340℃(Ⅱ段),压力1.5~2.5MPa,空速2.0NL/gFe·h(Ⅰ段),500~1000h ̄-1(Ⅱ段),H_2CO比0.5~1.5和气速1~2cm/s范围内,考察了工艺参数对反应性能的影响,1000h以上的寿命试验的平均结果为:合成气单程转化率65.1%,产率100g/Nm ̄3(Co+H_2),总烃生产达350g/Fe。使用富CO合成气时,达110g/Nm ̄3(CO+H_2)。实测的FT合成反应热为2938;5kJ/Nm ̄3(CO+H_2)。长期运转试验表明,工艺流程合理,设备操作和温度控制可靠。采用的浆液循环回路方法可初步分离蜡中的催化剂。  相似文献   

2.
用Cu-Co系催化剂可从合成气制C_1~C_6正构低碳醇。Cu-Co尖晶石化学组成均匀,能使活性中心均匀分布,为良好的催化剂前驱体。本工作用共沉淀法与的烧法制备了Cu-Co尖晶石化合物。XRD、DTA、TG等研究表明,当Cu/Co比为0.05~0.5时,得到单相的尖晶石化合物可作为合成低碳醇催化剂的前驱体。其中,共沉淀法制得的催化剂具有较高的催化活性与选择性。当Cu/Co比为0.35~0.45时共沉淀法催化剂的活性与选择性最高,醇时空产率0.15~0.20mlROH/mlcat./h,醇选择性>50%。控制适当的反应条件,可以得到所需的产品组成。  相似文献   

3.
本文介绍了以焦炉气中自有的NH_3为碱源,在PDS(双核酞菁钴磺酸盐)的催化作用下,脱除煤气中H_2S、HCN的工艺模拟研究,提出了新的焦炉气净化工艺流程,称为A-PDS工艺。选择出了适宜的工艺条件,可将煤气中H_2S由5~7g/m ̄3脱至20mg/m ̄3以下,脱除率达99%以上;可将HCN由0.8~1.3g/m ̄3脱至20mg/m ̄3以下,脱除率达98%。  相似文献   

4.
熔融碳酸盐燃料电池研究   总被引:5,自引:0,他引:5  
李乃朝  衣宝廉 《电化学》1996,2(1):89-95
以烧结Ni作电极,以LiAlO2无机膜作电池隔膜,组装成了电极而积28cm^2的小型熔融碳酸盐燃料电池,试验了各种工作条件对电池性能的影响,电池经多次启动性能无衰减,放电电流密度100mA/cm^2,电池电压0.95V,放电电流密度125mA/cm^2,电池输出功率114mW/cm^2,燃料气利用率80%,电池能量效率31%。  相似文献   

5.
以酒石酸-乙二胺为淋洗液的单柱离子色谱法同时测定磷酸中痕量钠(Ⅰ)和铁(Ⅲ)。淋洗液最佳浓度为4.0mmol.L ̄(-1)、酒石酸/1.0m mol·L ̄(-1)乙二胺。最低检测限为Na ̄+0.05μg/mL、 Fe3+ 0.45μg/mL。电导检测灵敏度为2.0μg/cm。线性范围Na ̄+、Fe3+0.2~1.5×103μg/mL、2.5~1.0×103μg/mL。相对平均偏差Na ̄+为2.03%、Fe3+为0.83%。平均回收率Na ̄+为98.26%、Fe3+为97.62%。本法简便、快速、准确、选择性好。  相似文献   

6.
高平  马祖福 《分子催化》1999,13(5):378-382
用稀土氧化物Ln2O3(Ln:La,Nd,Eu,Ho,Yb,Sm)对戊二酸锌进行改性,制备出新催化剂。在80℃,3.0 ̄3.5MPa条件下,该催化剂催化二氧化碳与环氧丙烷共聚,反应时间为6.5 ̄7.0h,催化活性达到3.0 ̄3.4g polym./(gcat.·h),转化率70.8% ̄79.7%,共聚物中碳酸酯单元分数48.4%,产品热分解温度238.1℃。  相似文献   

7.
以新指示反应高敏催化光度测定痕量钌   总被引:3,自引:0,他引:3  
钌(Ru ̄Ⅲ)对高碘酸钾氧化无色孔雀绿的显色体系有催化作用,借此催化光度测Ru ̄Ⅲ,灵敏度高。在20~30℃下30~60min内,以1cm吸收池内测得吸光度0.1为可准确测极限,则可测最低浓度为0.08ng·mL ̄(-1),若表示为间接摩尔吸光系数则 =2.0×10 ̄8mol ̄(-1)·L·cm ̄(-1)。工作曲线线性范围为0.04~0.36ng/mL(室温约为26℃).其它贵金属如Os ̄Ⅷ、Rh ̄Ⅲ、Au ̄Ⅲ、Ag ̄Ⅰ、Pd ̄Ⅱ、Pt ̄Ⅳ等至少可允许分别存在200ng/mL、1ng/mL、200ng/mL、3000ng/mL、25ng/mL和5ng/mL。测定了含所有贵金属和某些其它常见金属人工混合液中的痕量Ru ̄Ⅲ,不含Ir ̄Ⅳ时回收率为98.5%~101.0%,含2.3倍于Ru ̄Ⅳ重量的lr ̄Ⅳ时回收率为101.5%~112%。  相似文献   

8.
郑瑜  朱自莹 《结构化学》1994,13(3):216-220
合成并测定三价铁乙二酸配合物Na_3Fe(C_2O_4)_3.5H_2O的单晶结构。晶体属单斜晶系,空间群为C2/c,晶胞参数a=17.380(1),b=12.693(5),c=15.196(6),β=100.47(6)°,V=3297(3),Z=8,D_c=1.74g/cm ̄(-3).M_r=478.98,μ=10.51cm ̄(-1)。结构的偏离因子R=0.036,R_w=0.056。此外,还测定了化合物的红外、拉曼、紫外一可见吸收光谱、穆斯堡尔谱及磁化率等。并通这有关信息讨论了该化合物的结构。  相似文献   

9.
烟草中Fe,Co一阶导数分光光度法同时测定的研究   总被引:4,自引:0,他引:4  
本文研究了在pH4.0时,meso-四(4-磺酸基苯基)卟啉与铁、钴同时络合显色的反应条件以及一阶导数光谱行为。此体系一阶导数的灵敏度比零阶导数灵敏度高。Fe ̄(3+)~0.18μg/mL、Co ̄(2+)0~0.24μg/ml,范围内符合比耳定律;检测限为:Fe ̄(3+)=0.48ng/mL,Co ̄(2+)=0.2ng/mL。回收率为:Fe98.5%~100.8%,Co99.2%~101.3%。此方法用于烟草中痕量Fe、Co测定,与AAS值相比较,结果令人满意。  相似文献   

10.
合成了4种锰(Ⅲ)-苯甲酰丙酮缩乙二胺-有机碱配合物:Mn(bzacen)LClO_4.(L为哌嗪,吡啶,γ-甲基吡啶和乙腈),测定了配合物[Mn(bzacen)(CH_(3)CN)ClO_4]的结构.晶体属正交晶系.空间群P_nma.晶胞参数:a=0.9077(1)nm,b=1.5563(1)nm,c=1.7205(2)nm,V=2.4305nm ̄3,Z=4,D_c=1.48g/cm ̄3,D_m=1.49g/cm ̄3.配合物呈拉长八面体结构.对配合物的电子光谱和红外光谱进行了归属.  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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