不同载体镍基催化剂对1,4-丁炔二醇加氢性能的影响

采用等体积浸渍法将Ni分别负载在USY、ZSM-5、SBA-15、Al₂O₃和SiO₂ 5种载体上制备Ni质量分数为17%的负载型镍基催化剂,以1,4-丁炔二醇(BYD)加氢制1,4-丁二醇(BDO)为探针反应考察其催化性能。通过X射线衍射、N₂吸附-脱附、H₂程序升温还原及NH₃程序升温脱附对催化剂进行表征。结果表明,在不同载体的催化剂作用下,BYD的转化率均可达到99%以上,但BDO的选择性却有很大差异;其他条件相同时,Ni/SBA-15催化剂反应5 h时BDO的选择性达到83.1%,1,4-丁烯二醇(BED)的选择性为16.6%,且2-羟基四氢呋喃(HTHF)的选择性很低,这与Ni/SBA-15具有较大的比表面积和平均孔径、较弱的酸性和良好的活性金属组分镍分散性有关。进而筛选出在低温低压条件下BYD一步加氢制备BDO的镍基催化剂Ni/SBA-15。     

1,4-丁炔二醇加氢制1,4-丁烯二醇工艺及催化剂研究进展

论述1,4-丁烯二醇发展现状,简述1,4-丁烯二醇BYD加氢法、3,4-环氧-1-丁烯水解法和1,3-丁二烯法3种生产工艺特点.其中,BYD催化加氢法是生产BED技术最为成熟、应用最为广泛的生产工艺.BYD加氢反应是一个多步复杂反应.论述了BYD加氢催化反应过程以及3种催化剂(贵金属催化剂、过渡金属催化剂、骨架型Raney-Ni催化剂)在BYD加氢反应过程中的应用特点,指出Raney-Ni催化剂具有价格低、活性高的优点,开发中压下BYD加氢制备BED的Raney-Ni催化剂具有重要意义.     

固定床镍铝催化剂失活原因分析及解决措施

对Reppe法生产工艺中1,4-丁炔二醇(BYD)加氢制备1,4-丁二醇(BDO)所使用的固定床镍铝合金催化剂的失活原因进行了分析。找出了影响催化剂性能的关键因素,并给出了延长催化剂使用寿命的解决措施。采用优化措施后,一级反应器BYD加氢反应后副产丁醇质量分数比优化前减少了20%～40%,叔丁醇(TBA)质量分数减少了20%～40%,催化剂寿命可以延长20%～40%。通过延长BDO装置镍铝合金催化剂的使用寿命,可以减少副产物产生比例,降低生产成本,提高企业竞争力。     

1,4-丁炔二醇二段加氢Ni/Al_2O_3催化剂的研究

采用共沉淀法制备负载量为15%(质量分数)的1,4-丁炔二醇二段加氢Ni/Al2O3催化剂。考察反应温度、压力、时间、pH值和转速等因素对1,4-丁炔二醇二段加氢反应的影响。实验结果表明,在反应温度125℃、转速1 100r/min、反应时间3.6h、反应液pH值6.0、压力4.0MPa条件下,所制备的催化剂具有较好的活性,其收率达到90%。     

焙烧温度对1,4-丁炔二醇加氢制1,4-丁烯二醇Ni-Al_2O_3催化剂性能影响

采用机械化学法制备Ni-Al_2O_3催化剂,通过EDX、XRD、H_2-TPR、BET、SEM、TEM、NH_3-TPD等进行物化结构表征,以水相1,4-丁炔二醇(BYD)加氢制1,4-丁烯二醇(BED)为探针反应,研究焙烧温度对Ni-Al_2O_3催化剂加氢性能的影响。结果表明,焙烧温度600℃所制备的MCT600催化剂比表面积最大,为277 m~2/g。催化剂表面的活性组分Ni负载量(23.14%)超过理论负载量(20%),表面酸(强酸)酸强度较弱。在反应压力4 MPa、温度110℃、搅拌转速500 r/min、反应时间3 h的条件下,MCT600加氢性能较好,BYD转化率25.77%,BED选择性94.08%,收率24.25%。     

助剂Co对1,4-丁炔二醇加氢制1,4-丁烯二醇Ni-Al_2O_3催化剂性能影响

采用机械化学法制备不同Co含量的Co-Ni-Al_2O_3催化剂。通过XRD、H_2-TPR、N_2吸附-脱附、SEM、XPS等表征手段和1,4-丁炔二醇(BYD)加氢制1,4-丁烯二醇(BED)评价实验,考察不同Co含量对Ni基催化剂结构和性能的影响。结果表明,Co含量为1%的催化剂Ni金属呈无定型态分布,比表面积大,为295 m²/g。试样Ni-Co-1加氢性能最好,BYD转化率为30.19%,BED选择性为98.32%,收率为29.68%。这与该试样活性组分Ni呈无定型态、具有较大的比表面积、表面形貌为絮状体和活性金属Ni结合能较弱有较大关联。助剂Co在1%的添加量下具有较好的分散作用和"限域效应"。     

助剂Co对1,4-丁炔二醇加氢制1,4-丁烯二醇Ni-Al_2O_3催化剂性能影响

采用机械化学法制备不同Co含量的Co-Ni-Al_2O_3催化剂。通过XRD、H_2-TPR、N_2吸附-脱附、SEM、XPS等表征手段和1,4-丁炔二醇(BYD)加氢制1,4-丁烯二醇(BED)评价实验,考察不同Co含量对Ni基催化剂结构和性能的影响。结果表明,Co含量为1%的催化剂Ni金属呈无定型态分布,比表面积大,为295 m~2/g。试样Ni-Co-1加氢性能最好,BYD转化率为30.19%,BED选择性为98.32%,收率为29.68%。这与该试样活性组分Ni呈无定型态、具有较大的比表面积、表面形貌为絮状体和活性金属Ni结合能较弱有较大关联。助剂Co在1%的添加量下具有较好的分散作用和"限域效应"。     

催化加氢合成6-氨基-7-氟-2H-1,4-苯并口恶嗪-3(4H)-酮

6-氨基-7-氟-2H-1,4-苯并口恶嗪-3(4H)-酮(Ⅱ)是合成除草剂丙炔氟草胺的关键中间体,该文采用雷尼镍催化加氢还原7-氟-6-硝基-2H-1,4-苯并口恶嗪-3(4H)-酮(Ⅰ)高收率的制得了目标化合物Ⅱ,确定了最佳合成工艺条件:反应温度80℃,反应时间5 h,催化剂用量为原料质量的5%,氢气压力6 MPa,产品的收率95.2%,质量分数98.5%,溶剂和催化剂循环使用5次,对收率和产品质量分数无影响。产品结构经元素分析、红外光谱、核磁共振确证。     

1,4-丁炔二醇加氢过程研究进展

1,4-丁炔二醇(BYD)加氢产物1,4-丁二醇(BDO)是重要的有机化工原料,工业上该加氢过程存在反应压力高、设备投资大、催化剂易失活等问题。本文综述了1,4-丁炔二醇加氢反应过程的特点,对比了不同BYD加氢工艺并分析了各工艺特点和面临的问题,回顾了Ni基、Pt基、Pd基加氢催化剂的开发进展,简述了新型加氢反应器的特点与研究进展。基于催化剂表面氢浓度对BYD加氢反应过程影响显著的特点,提出通过强化反应过程气液、液固传质效率对BYD加氢过程进行改进,以期降低反应压力。通过加入金属助剂和改变载体性质开发加氢催化剂,提高催化剂活性和稳定性。最后总结展望了开发BYD低压加氢剂催化剂和低压加氢反应器的发展趋势,结合BYD加氢Ni基催化剂具有磁性的特点,提出磁场辅助流化床对BYD加氢过程的潜在应用前景。     

助剂对Ni/SiO2催化剂1,4-丁炔二醇加氢性能的影响

通过分步浸渍法在Ni/SiO 2催化剂中分别引入Zn、Cu、La、Mo、Co金属助剂,结合N 2物理吸附-脱附、XRD、H 2-TPR和NH 3-TPD等表征手段研究金属助剂对1,4-丁炔二醇加氢性能的影响。结果发现,Mo的引入使Ni/SiO 2催化剂的初始活性大幅增加,但反应2 h后活性下降,归因于催化剂表面酸中心使催化剂积炭失活;引入Cu、La及Co后的催化剂活性较低,推测是由于催化剂表面产生强吸附氢物种,不利于1,4-丁炔二醇加氢反应进行;与其他样品相比,Zn的引入使催化剂保持了Ni/SiO 2催化剂高的1,4-丁炔二醇加氢活性,同时可有效降低产物中2-羟基四氢呋喃副产物含量,提高目标产物1,4-丁二醇收率。     

Effect of preparation methods on the hydrocracking performance of NiMo/Al2O3 catalysts

In this work, NiMo catalysts with various contents of MoO_3 were prepared through incipient wetness impregnation by a two-step method(NM-x A) and one-pot method(NM-xB). The catalysts were then characterized by XRD, XPS, NH_3-TPD, H_2-TPR, HR-TEM, and N2 adsorption–desorption technologies.The performance of the NiMo/Al_2O_3 catalysts was investigated by hydrocracking low-temperature coal tar. When the MoO_3 content was 15 wt%, the interaction between Ni species and Al_2O_3 on the NM-15 B catalyst was stronger than that on the NM-15 A catalyst, resulting in the poor performance of the former.When the MoO_3 content was 20 wt%, MoO_3 agglomerated on the surface of the NM-20 A catalyst, leading to decreased number of active sites and specific surface area and reduced catalytic performance. The increase in the number of MoS_2 stack layers strengthened the interaction between Ni and Mo species of the NM-20 B catalyst and consequently improved its catalytic performance. When the MoO_3 content reached 25 wt%, the active metals agglomerated on the surface of the NiMo catalysts, thereby directly decreasing the number of active sites. In conclusion, the two-step method is suitable for preparing catalysts with large pore diameter and low MoO_3 content loading, and the one-pot method is more appropriate for preparing catalysts with large specific surface area and high MoO_3 content. Moreover, the NMx A catalysts had larger average pore diameter than the NM-xB catalysts and exhibited improved desulfurization performance.     

对苯二甲酸-丁二醇催化单酯化反应动力学(英文)

The chemical kinetics of the monoesterification between terephthalic acid (TPA) and 1,4-butanediol (BDO) catalyzed by a metallo-organic compound was studied using the initial rate method. The experiments were carried out in the temperature range of 463-483 K, and butylhydroxyoxo-stannane (BuSnOOH) and tetrabutyl titanate [Ti(OBu)4] were used as catalyst respectively. The initial rates of the reaction catalyzed by BuSnOOH or Ti(OBu)4 were measured at a series of initial concentrations of BDO (or TPA) with the concentration of TPA (or BDO) kept constant. The reaction orders of reagents were determined by the initial rate method. The results indicate that the reaction order for TPA is related with the species of catalyst and it is 2 and 0.7 for BuSnOOH and Ti(OBu)4 respectively. However, the order for BDO is the same 0.9 for the two catalysts. Furthermore, the effects of temperature and catalyst concentration are investigated, and the activation energies and the reaction rate constants for the two catalysts were deter-mined.     

甘油水蒸汽重整制氢Ni、Co、Fe催化剂的研究

采用等体积浸渍法制备了催化剂,研究了Ni/Al2O3,Fe/Al2O3,CoMo/Al2O3和NiCo/Al2O3催化剂对甘油水蒸汽重整制氢反应的催化效果,对催化剂进行BET、TPR、XRD表征,以氢产率为实验指标对催化剂进行了评价。研究结果表明,CoMo/Al2O3催化剂在温度650℃氢产率6.02。NiCo/Al2O3催化剂在温度600℃、水醇比16、液空速0.12 h-1条件下的氢产率为6.08。催化剂活性次序为NiCo/Al2O3Co-Mo/Al2O3Ni/Al2O3Fe/Al2O3。     

Al2O3-ZrO2负载Ni2P催化剂加氢脱硫脱氮活性

采用浸渍-沉淀法制备Al2O3-ZrO2复合氧化物,通过程序升温还原法制备Ni2P/Al2O3-ZrO2催化剂。运用X射线衍射、N2吸附-脱附、X射线光电子能谱技术对载体和催化剂进行表征,并以噻吩加氢脱硫、吡啶加氢脱氮反应为探针考察复合氧化物对Ni2P催化剂加氢活性的影响。结果表明,在Al2O3表面引入少量ZrO2,既保持了γ-Al2O3大比表面积的结构优势,又减少了P或Ni与Al2O3表面的接触,促进Ni2P的形成。载体中ZrO2质量分数20%的Ni2P/Al2O3-ZrO2催化剂活性最高,载体焙烧温度过高会导致催化剂活性下降。     

溶胶-沉积镍基催化剂及其在 裂解C＋9 加氢中的应用

研究了溶胶-沉积法制备的高镍含量负载型金属催化剂,考察了镍含量、载体组成及焙烧温度等对催化剂性能的影响,对制备的催化剂进行了BET、XRD及TPR表征。结果表明,催化剂表面积和孔径随镍含量增加而减小;溶胶-沉积NiO/Al₂O₃-SiO₂中Ni以高分散的NiO形式存在,与载体相互作用较强,没有NiAl₂O₄尖晶石生成;催化剂比表面积较大［（220~240） m²·g^-1 ］,孔径适中［（8~10） nm］。溶胶-沉积Ni/Al^₂O₃-SiO₂催化剂具有良好的催化性能,将其应用于裂解C^＋₉ 加氢反应,效果较好,烯烃加氢率达90%,芳烃损失为零,催化剂性能稳定,耐胶质能力强。     

硫改性镍催化剂丁烯-1双键临氢异构性能

将Ni/Al_2O_3催化剂浸渍于有机多硫化物(TPS-37)中制备得到硫改性Ni/Al_2O_3催化剂。采用X射线荧光光谱(XRF)、热重-质谱(TG-MS)联用、X射线光电子能谱仪(XPS)和程序升温还原(TPR)等方法对催化剂进行表征,并考察了硫改性Ni/Al_2O_3催化剂上丁烯-1双键临氢异构性能。结果表明,硫改性Ni/Al_2O_3催化剂经高温氢气活化及甲苯萃取后,催化剂上硫含量基本不变。硫与催化剂之间存在较强的相互作用,使氧化镍在相对较低的温度下被H2还原;硫改变了Ni金属周围电子环境,从而显著改善催化剂的双键临氢异构性能。在反应温度60℃,氢压1.6 MPa,氢气和碳四烃物质的量之比(氢烃比)为0.013的条件下,硫改性Ni/Al_2O_3催化剂催化丁烯-1双键临氢异构反应,丁烯-1转化率可达92.6%,丁烯-2选择性为97.5%。催化剂稳定性实验结果表明,硫改性催化剂催化性能好,稳定性优良。     

Skeletal Ni catalysts prepared from Ni–Al alloys rapidly quenched at different rates: Texture,structure and catalytic performance in chemoselective hydrogenation of 2-ethylanthraquinone

Skeletal Ni catalysts (RQ Ni) prepared by alkali leaching of rapidly quenched Ni–Al alloys have been systematically characterized, focusing on the effect of the cooling rate during alloy preparation. It is found that the residual Al content, texture, structure, surface hydrogen species, and active sites of the RQ Ni catalysts can be controlled by the cooling rate of the Ni–Al alloys. In liquid-phase hydrogenation of 2-ethylanthraquinone (eAQ), the RQ Ni catalyst with higher cooling rate favors hydrogenation of the carbonyl group and retards the saturation of the aromatic ring and the formation of the degradation products, thus leading to a higher yield of H₂O₂. Based on the characterizations, the improved selectivity is ascribed to the dominant population of strongly chemisorbed hydrogen, which is inactive for the hydrogenation of the aromatic ring, along with the electronic interaction between residual metallic Al and Ni, favoring a carbonyl group-bonded configuration of eAQ on the catalyst.     

1,4-丁二醇低压加氢催化剂国产化及其工业应用

Reppe法ISP工艺是国内较为普遍使用的1,4-丁二醇生产工艺,但低压加氢催化剂长期依赖于进口,价格高、交货期长及付款方式严苛。对1,4-丁二醇低压加氢催化剂国产化开发过程进行了介绍,包括催化剂生产、物性指标分析和工业装置应用等方面。通过6个月的工业生产装置100%负荷运行数据及70%负荷运行数据可以看出,使用国产催化剂,反应器出口产品物料符合生产要求;国产催化剂平均单耗与进口剂一致。根据催化剂运行时沉降槽遗留物料催化剂含量对比,国产剂在沉降性能方面略微优于进口剂。因此,国产催化剂完全能够满足实际生产要求,成为进口催化剂的有效替代。