信息化背景下的石油化工催化剂生产成本统筹分析研究

基于会计信息化石油化工催化剂制备工艺复杂、成本核算难等问题，采用化学还原和光还原法在g-C₃N₄超薄纳米片(CNS)上负载Pt NPs制备Pt/g-C₃N₄催化剂，对比分析了2种制备方法下Pt/g-C₃N₄催化剂的微观结构和光催化性能。结果表明，2种方法都可以在CNS表面成功负载Pt NPs,且Pt含量不会对负载到CNS表面的Pt NPs数量和粒径产生明显影响；催化剂比表面积从大至小顺序依次为：CNS、Pt/CNS-CR、CNB。随着光照射时间的延长，Pt/CNS-CR的产氢速率会随着Pt含量增加先增加后减小，2%-Pt/CNS-CR取得最大产氢速率，继续增加Pt含量反而会使得产氢速率减小。Pt/CNS-CR和Pt/CNS-PR催化剂的产氢速率都高于2%-Pt/CNB-CR,且2%-Pt/CNS-CR的产氢速率约为2%-Pt/CNS-PR的6.92倍。     

一维TiO2-Al2O3载体的制备及其在加氢脱氮中的应用

为提高现有负载型NiMoS催化剂的加氢活性,以碳纳米管为结构导向剂,分别采用浸渍法和溶胶-凝胶法制备了2种一维TiO₂-Al₂O₃载体,并采用共浸渍法制备了相应的负载型NiMoS催化剂,探究了不同结构的载体对NiMoS/TiO₂-Al₂O₃催化剂加氢脱氮性能的影响。结果表明,当选择以溶胶-凝胶法制备的一维TiO₂-Al₂O₃为载体时,NiMoS/TiO₂-Al₂O₃催化剂上的加氢脱氮活性较高,在350℃、氢压为3 MPa、转速为400 r/min的条件下反应4 h,喹啉的转化率达到99%以上,脱氮率达到40.75%。     

超临界流体沉积制备Pt/TiO2工艺条件探究及其催化氧化甲醛性能

为了提高Pt在TiO₂上的分散，进一步提高Pt/TiO₂催化氧化甲醛活性，采用超临界流体沉积(SCFD)方法制备Pt/TiO₂,并对沉积工艺条件进行探索。对比不同催化剂Pt/TiNT和Pt/P25的催化活性，并采用TEM、N₂吸附-脱附、TPR和XPS等对两种催化剂进行表征。结果表明，采用共溶剂(V_乙醇∶V_乙二醇=1∶1)、沉积时间1 h、沉积温度70℃及质量分数0.4%的Pt负载量时，催化剂的催化性能较佳，室温条件下甲醛在Pt/TiNT和Pt/P25上均发生了完全催化氧化反应，Pt/TiNT使甲醛在16 h内净化了82.4%(降解率近100%),Pt/P25使甲醛净化了52.4%(降解率70.3%)。表征结果表明，TiNT管状阵列结构在SCFD中更有利于活性组分的有效分散，Pt和TiNT之间具有更强的相互作用，催化剂表面具有更多的负电荷和氧空位，因而表现出更高的催化活性。     

纳/微复合结构TiO2负载催化剂的加氢脱硫性能

以传统固相烧结法制备的不稳定的层状K₂Ti₂O₅为前驱体, 直接将钛酸钾晶须进行离子交换得到具有纳微复合结构的TiO₂载体, 等体积浸渍法制备出MoO₃/TiO₂催化剂, 运用SEM、XRD、BET、TEM等技术手段对载体和催化剂进行表征, 并考察了该TiO₂复合结构负载催化剂的加氢脱硫催化活性。SEM和XRD分析显示:该纳微米复合结构是由纳米颗粒与微米晶须构成的特殊结构, 拥有不同形貌和尺寸的TiO₂却具有相同的锐钛矿相。与单独TiO₂纳米粒子和TiO₂晶须相比, TiO₂复合结构负载催化剂表现出更佳的脱硫催化能力, 在温度310℃、压力2.1 MPa、体积空速6 h^-1、氢/油体积比600条件下, 催化剂表现出优异的DBT脱硫性能。     

TiO2载体特性对二苯并噻吩加氢脱硫性能的影响

以自制的大比表面介孔二氧化钛晶须作为加氢脱硫催化剂的载体,采用一步浸渍法制备了MoO₃-NiO/TiO₂催化剂,并用 X 射线衍射、N₂ 吸附-脱附、SEM、拉曼衍射等技术对载体和催化剂进行了表征,考察了TiO₂晶须材料作为二苯并噻吩(DBT)上加氢脱硫(HDS)催化剂载体的性能及优越性,并详细考察了不同TiO₂载体的晶型与比表面积对催化剂加氢脱硫反应活性的影响。结果表明,TiO₂介孔晶须具有较为活泼的锐钛矿相和晶须形貌,同时提供了大的比表面积和特殊的孔道结构,在温度280℃、氢分压2.0 MPa、氢/油体积比400、体积空速4 h^-1的温和条件下,DBT转化率即可接近100%。比表面积相近时,催化剂的脱硫效果依次为锐钛矿相>混晶>金红石相;同为锐钛矿相TiO₂载体,催化剂的脱硫效果随着比表面的增大而增加。     

载体制备方法对Ni/TiO2催化剂顺酐液相加氢性能的影响

为了制备高活性和高选择性催化剂,实现顺酐下游加氢衍生物的定向合成,分别采用水热法、沉淀法和溶胶-凝胶法制备TiO2载体,并以浸渍法制备Ni质量分数为10%的Ni/TiO₂催化剂。采用N₂低温物理吸附、XRD、H₂-TPR及H₂-TPD等方法对催化剂进行表征,并评价催化剂的顺酐液相加氢性能。结果表明,以溶胶-凝胶法制备TiO₂为载体的催化剂具有最高的CC及CO加氢活性,在反应温度240 ℃和氢压5 MPa条件下,顺酐转化率为100%,γ-丁内酯选择性为52.2%,是相同反应条件下水热法TiO₂负载Ni催化剂的3.3倍和沉淀法TiO₂负载Ni催化剂的6.2倍。产生这一现象的原因与溶胶-凝胶法制备的TiO₂以锐钛矿和金红石混合晶相存在有关。     

NbO x 掺杂对Pt/TiO2催化燃烧氯乙烯的促进作用

通过制备Pt/Nb _x /TiO₂研究了NbO _x 在催化燃烧氯乙烯中的作用;采用XRD、XPS、H₂-TPR、NH₃-TPD与Py-FT-IR表征了NbO _x 对于催化剂组织结构、氧化还原以及酸碱性的影响。负载NbO _x 可促进Pt/TiO₂反应性能的提高,当Nb/Ti摩尔比为0.09时,即Pt/Nb_0.09/TiO₂可在246℃实现90%氯乙烯的转化;与Pt/TiO₂相比,达到相同转化率的温度向低温偏移69℃。NbO _x 也影响了催化燃烧过程中的含氯副产物的总浓度和分布。催化剂表征结果发现NbO _x 的引入可进一步增加Pt与载体（TiO₂）之间的相互作用,提高催化剂的表面活性氧物种的浓度,进而促进了催化剂氧化还原性能的提高。催化剂表面的总酸量随着NbO _x 含量的增加而降低,尤其是表面Lewis酸量。因此,催化剂表面的酸量和酸分布不是决定反应性能的唯一因素,而低温的氧化还原性更有利于催化剂性能的提高。     

NbO x 掺杂对Pt/TiO2催化燃烧氯乙烯的促进作用

通过制备Pt/Nb _x /TiO₂研究了NbO _x 在催化燃烧氯乙烯中的作用;采用XRD、XPS、H₂-TPR、NH₃-TPD与Py-FT-IR表征了NbO _x 对于催化剂组织结构、氧化还原以及酸碱性的影响。负载NbO _x 可促进Pt/TiO₂反应性能的提高,当Nb/Ti摩尔比为0.09时,即Pt/Nb_0.09/TiO₂可在246℃实现90%氯乙烯的转化;与Pt/TiO₂相比,达到相同转化率的温度向低温偏移69℃。NbO _x 也影响了催化燃烧过程中的含氯副产物的总浓度和分布。催化剂表征结果发现NbO _x 的引入可进一步增加Pt与载体（TiO₂）之间的相互作用,提高催化剂的表面活性氧物种的浓度,进而促进了催化剂氧化还原性能的提高。催化剂表面的总酸量随着NbO _x 含量的增加而降低,尤其是表面Lewis酸量。因此,催化剂表面的酸量和酸分布不是决定反应性能的唯一因素,而低温的氧化还原性更有利于催化剂性能的提高。     

制备条件对Ni2P/TiO2-Al2O3催化剂加氢脱硫性能的影响

采用溶胶-凝胶法制备了TiO₂-Al₂O₃复合载体, 以柠檬酸为络合剂, 浸渍法制备了负载型Ni₂P/TiO₂-Al₂O₃催化剂前体, 程序升温H₂还原法制备了Ni₂P/TiO₂-Al₂O₃催化剂, 并用 X 射线衍射(XRD)、N₂吸附比表面积(BET)测定技术对催化剂的结构和性质进行了表征, 考察了浸渍方法、Ni/P摩尔比、Ni₂P负载量对其进行的二苯并噻吩(DBT)加氢脱硫(HDS)性能的影响。结果表明, 当Ni/P比低于1:1时, 能得到单一的Ni₂P物相;当Ni/P比为2:1时, 开始出现Ni₃P物相。采用Ni/P比为1:1、Ni₂P负载量为30%、采用共浸渍方法制备的Ni₂P/TiO₂-Al₂O₃催化剂具有最好的活性, 在360℃、3.0MPa、氢油比500 (体积比)、液时体积空速2.0h^-1的条件下反应4h时, 二苯并噻吩转化率为99.5%。     

Pt/USY催化剂上四氢萘选择性开环反应

通过USY分子筛载体上负载Pt制备Pt/USY催化剂，考察Pt/USY催化剂对四氢萘选择性开环反应的影响。结果表明，USY分子筛载体负载Pt后，四氢萘转化率提高，且明显改善开环的选择性。通过工艺条件的研究，得知在空速为2 h^-1、氢油体积比为750∶1、反应压力为4 MPa和反应温度为280℃时，Pt_0.4/USY催化剂性能最好，四氢萘转化率大于99%,C₁₀产物收率大于94%,开环选择性高于38%。     

Pt/TiO_2催化二甲醚部分氧化重整制氢

二甲醚是一种理想的氢载体,可用于解决氢的储存和运输。以Pt/TiO_2为部分氧化催化剂,结合Ni/Al_2O_3重整催化剂,考察钛前驱体和焙烧温度对二甲醚部分氧化重整制氢反应的影响。结果表明,以Ti(C4H9O)4为原料制备的TiO_2为金红石相,Ti(SO4)2或Ti O(OH)2为原料制备的TiO_2为锐钛矿相;以Ti(C4H9O)4为原料制备的Pt/TiO_2-E催化剂催化性能略好,转化率接近100%,H2收率约90%,表明金红石相TiO_2负载的Pt催化剂略佳;以Ti(SO4)2为原料制备的Pt/TiO_2-S催化剂500℃焙烧可获得金红石相TiO_2。与Pt/Al_2O_3催化剂相比,Pt/TiO_2催化剂具有更好的催化性能,H2收率超过90%,而Pt/Al_2O_3催化剂H2收率约80%。     

Pt/TiO2/ZSM-5催化剂的制备及其催化转化正丁烷

采用溶胶-凝胶法和等体积浸渍法,分别对ZSM-5分子筛进行TiO₂改性和Pt负载,获得了具有脱氢-裂解双功能的Pt/TiO₂/ZSM-5催化剂,采用XRD、N₂吸附-脱附、TEM、XPS和NH₃-TPD对样品的晶体结构,孔结构、形貌、活性金属价态和酸性质等进行了表征,并研究了正丁烷在此催化剂上催化转化制备低碳烯烃的反应规律。研究结果表明,TiO₂的引入,一方面使得改性后的ZSM-5分子筛获得了额外的酸性中心,特别是强酸性位含量的增加,有助于促进正丁烷的活化;另一方面Pt与TiO₂之间存在“金属-载体”强相互作用（SMSI）,在H₂还原气氛下,Pt能够促进TiO₂的还原,生成Ti³⁺物种,而Ti³⁺的存在增加了Pt周围的电荷密度,降低了Pt对低碳烯烃（C₂⁼～C₃⁼）的吸附能力,抑制了深度脱氢和生焦反应,从而提高双功能催化剂对烯烃的选择性。当H₂还原温度为450℃时,Pt/10TiO₂/ZSM-5催化剂在625℃下的正丁烷转化率为76.1%,低碳烯烃（C₂⁼～C₃⁼）收率为50.9%,分别比Pt/ZSM-5催化剂提高了16.7%和12.6%。     

Structural peculiarities of TiO2 and Pt/TiO2 catalysts for the photocatalytic oxidation of aqueous solution of Acid Orange 7 Dye upon ultraviolet light

TiO₂ (anatase) with different microstructure was synthesized by thermal hydrolysis of the titanyl sulfate and studied by X-ray powder diffraction, high resolution transmission electron microscopy and UV–vis diffuse reflectance spectroscopy. The effect of titanium dioxide structure, regular or distorted, on the photocatalytic degradation of Acid Orange 7 Dye (AO7) in water upon ultraviolet light was studied. It was found that synthesized TiO₂ possesses a relatively high reactivity when illuminated but also show different adsorption in the dark. The relationship between these behaviors depends on the real structure of the catalysts. Catalysts with a perfect structural ordering formed after heating at temperature higher than 500 °C show better photocatalytic performance. Small amount of Pt added into the TiO₂ structure was found to improve further the catalyst reactivity. Pt-modified titania catalysts oxidize AO7 more efficiently than P-25 Degussa TiO₂. Doping effect of Pt on the structural and photocatalytic properties of the samples is discussed.     

Catalytic oxidation of low concentration formaldehyde over Pt/TiO2 catalyst

Formaldehyde(HCHO) is an important indoor pollutant.Catalytic oxidize low concentration HCHO is an effective way to eliminate indoor pollution.In this study,a series of Pt/TiO_2 catalysts are prepared by impregnation and reduced by NaBH_4.The effects of loading amount of Pt and cry stal type of TiO_2 on the physical and chemical properties and the catalytic performance in HCHO oxidation reaction are investigated.The results show that the quantity of active site and the oxygen vacancy of catalysts increa sed with increasing Pt content,which is beneficial to promote the further performance of catalysts.Nevertheless,with the further rises of Pt content,the specific surface area further decreases,and the proportion of Pt~(2+) species on the catalyst surface which is significant to catalytic properties also decreases,causing catalytic performance decreases.Compared with the catalyst supporting on rutile,the Pt/α-TiO_2 catalyst supporting on anatase has larger specific surface area,more Pt~(2+) phase and easier to form oxygen vacancy in the support,which cause better catalytic performance.The catalyst with Pt content of0.1 wt% and supported by anatase TiO_2 has the best catalytic performance.The HCHO conversion efficiency reaches 98% and 100% at 50℃ and 100 ℃, and the stabilization time is longer than 140 h.     

Performance and characterization of supported metal catalysts for complete oxidation of formaldehyde at low temperatures

Activities of a series of metals (Pt, Pd, Rh, Cu, Mn) supported on TiO₂ were investigated for the catalytic oxidation of formaldehyde. Among them, Pt/TiO₂ was found to be the most promising catalyst. Nitrogen adsorption, hydrogen chemisorption, X-ray diffraction (XRD), transmission electron microscopy (TEM) and temperature programmed reduction (TPR) by H₂ were used to characterize the platinum catalysts. Using Ce_0.8Zr_0.2O₂, Ce_0.2Zr_0.8O₂, SiO₂ as supports instead of TiO₂, the activity sequence of 0.6 wt.% platinum with respect to the supports is TiO₂ > SiO₂ > Ce_0.8Zr_0.2O₂ > Ce_0.2Zr_0.8O₂, and this appears to be correlated with the dispersion of platinum on supports rather than the specific surface areas of the catalysts. Platinum loading on TiO₂ has a great effect on the catalytic activity, and 0.6 wt.% Pt/TiO₂ catalyst was observed to be the most active, which could be attributed to the well-dispersed platinum surface phase. The reduction temperature greatly affects the particle size and, consequently, the catalytic activity. The smaller particle size of platinum, due to its high dispersion on support, has a positive effect on catalytic performance. Increasing formaldehyde concentration and space velocity exhibits an inhibiting effect on the catalytic activity.     

The role of the oxidic support on the deactivation of Pt catalysts during the CO2 reforming of methane

Pt supported on γ-Al₂O₃, TiO₂ and ZrO₂ are active catalysts for the CO₂ reforming of methane to synthesis gas. The stability of the catalysts increased in the order Pt/γ-A1₂O₃ < Pt/TiO₂ < Pt/ZrO₂. For all catalysts, the decrease in activity with time on stream is caused by carbon formation, which blocks the active metal sites for reaction. With Pt/TiO₂ and Pt/ZrO₂, deactivation started immediately after the start of the reaction, while the Pt/γ-A1₂O₃ catalyst showed an induction period during which carbon was accumulated without affecting the catalytic activity.     

Rh-based catalysts for catalytic dechlorination of aromatic chloride at ambient temperature

Catalytic dechlorination of chlorotoluene to toluene was carried out using several supported Rh-based catalysts in a 2-propanol solution of NaOH at ambient temperature (27°C). A carbon-supported Rh catalyst (Rh/C) showed high catalytic activity, although an induction period was involved in the reaction and the activity of the catalyst reduced during storage in air. The existence of Pt on the Rh catalyst was effective in overcoming the activity reduction by exposure to air and gave the reaction without any induction period. The composite Rh–Pt catalyst supported on TiO₂ as well as on carbon was much more active for the reaction than the catalysts supported on SiO₂, MgO and Al₂O₃.     

Low-temperature catalytic combustion of methanol and its decomposed derivatives over supported gold catalysts

Gold can be compared favorably with Pd and Pt in the catalytic combustion of CH₃OH, HCHO and HCOOH when it is deposited on some reducible metal oxides (-Fe₂O₃, TiO₂, etc.). While the supported gold catalysts are less active in H₂ oxidation, they exhibit much higher activities in CO oxidation. For Au/TiO₂, the effect of catalyst preparation was further investigated. Since the activity for CO oxidation of the gold catalysts is not depressed but enhanced by moisture, they are practically applicable to CO removal from air at room temperature. Gold supported on manganese oxide is especially effective in the selective CO removal from hydrogen, indicating its potential applicability to polymer electrolyte fuel cells using the reformed gas of methanol.     

Molecular structure–reactivity relationships for the oxidation of sulfur dioxide over supported metal oxide catalysts

The catalytic oxidation of sulfur dioxide to sulfur trioxide over several binary (M_xO_y/TiO₂) and ternary (V₂O₅/M_XO_Y/TiO₂) supported metal oxide catalysts was systematically investigated. The supported metal oxide components were essentially 100% dispersed as surface metal oxide species, as confirmed by Raman spectroscopy characterization. The sulfur dioxide oxidation turnover frequencies of the binary catalysts were all within an order of magnitude (V₂O₅/TiO₂>Fe₂O₃/TiO₂>Re₂O₇/TiO₂  CrO₃/TiO₂  Nb₂O₅/TiO₂>MoO₃/TiO₂  WO₃/TiO₂). An exception was the K₂O/TiO₂ catalysts, which is essentially inactive for sulfur dioxide oxidation. With the exception of K₂O, all of the surface metal oxide species present in the ternary catalysts (i.e., oxides of V, Fe, Re, Cr, Nb, Mo and W) can undergo redox cycles and oxidize SO₂ to SO₃. The turnover frequency for sulfur dioxide oxidation over all of these catalysts is approximately the same at both low and high surface coverages. This indicates that the mechanism of sulfur dioxide oxidation is not sensitive to the coordination of the surface metal oxide species. A comparison of the activities of the ternary catalysts with the corresponding binary catalysts suggests that the surface vanadium oxide and the additive surface metal oxide redox sites act independently without synergistic interactions. The V₂O₅/K₂O/TiO₂ catalyst showed a dramatic reduction in the catalytic activity in comparison to the unpromoted V₂O₅/TiO₂ catalyst. The ability of K₂O to significantly retard the redox potential of the surface vanadia species is primarily responsible for the lower catalytic activity of the ternary catalytic system. The fundamental insights generated from this research can potentially assist in the molecular design of the air pollution control catalysts: (1) the development of catalysts for low temperature oxidation of SO₂ to SO₃ during sulfuric acid manufacture (2) the design of efficient SCR DeNO_x catalysts with minimal SO₂ oxidation activity and (3) improvements in additives for the simultaneous oxidation/sorption of sulfur oxides in petroleum refinery operations.     

The effects of SO2 on the oxidation of CO and propane on supported Pt and Au catalysts

The catalytic activities of Pt and Au supported on TiO₂ were compared with respect to the oxidation of CO and propane. While the Au catalysts showed higher activities for CO oxidation, the Pt catalysts were more active for propane combustion. A strong de-activation of the CO oxidation activity by SO₂ was observed only over the TiO₂-supported Au catalyst, indicating that SO₂ can block the active sites for CO oxidation over Au catalysts. The results are consistent with a model in which the perimeter sites have a special role in the CO oxidation reaction over Au catalysts.