摘要:
A process is described for converting a precatalyst which comprises an inert support, an organic carbon source and a multimetal oxide comprising silver and vanadium to a gas phase oxidation catalyst which comprises the inert support and a catalytically active silver vanadium oxide bronze, by treating the precatalyst thermally at a temperature of at least 350° C. in a gas atmosphere which comprises less than 10% by volume of oxygen, wherein, before the thermal treatment, the amount of the carbon source in the precatalyst is adjusted to a value below a critical amount The carbon content is reduced by burning-off at a temperature of from 80 to 200° C. in an oxygenous atmosphere with decomposition of a portion of the carbon source. The catalysts obtained serve for the gas phase partial oxidation of aromatic hydrocarbons to aldehydes, carboxylic acids and/or carboxylic anhydrides.
摘要:
A multimetal oxide of the formula I, Aga-cQbMcV2Od*e H2O, I where a is from 0.3 to 1.9, Q is an element selected from among P, As, Sb and/or Bi, is from 0 to 0.3, M is a metal selected from among Nb, Ce, W, Mn, Ta, Pd, Pt, Ru and/or Rh, c is from 0.001 to 0.5, with the proviso that (a-c)≧0.1, d is a number which is determined by the valence and abundance of the elements other than oxygen in the formula I and e is from 0 to 20, and also precatalysts and catalysts produced therefrom for the partial oxidation of aromatic hydrocarbons are described.
摘要:
Multimetal oxides corresponding to the general formula (I), processes for their preparation, precatalysts containing such oxides and catalysts made therefrom for gas phase partial oxidation of hydrocarbons: Aga-cQbMcV12Od.eH2O (I)wherein a represents a number having a value of 5 to 9; Q represents an element selected from the group consisting of P, As, Sb, Bi and mixtures thereof; b represents a number having a value of 0.2 to 3; M represents a metal selected from the group consisting of Li, Na, K, Rb, Cs, Tl, Mg, Ca, Sr, Ba, Cu, Zn, Cd, Pb, Cr, Au, Al, Fe, Co, Ni, Ce, Mn, Nb, W, Ta, Mo and mixtures thereof; c represents a number having a value of less than 1; d represents a number having a value of which is determined by the valency and frequency of Ag, Q, M and V in the formula (I); and e represents a number having a value of 0 to 20; wherein the multimetal oxide has a crystal structure wherein its powder X-ray diffractogram includes reflections at at least 5 interplanar spacings selected from the group of 7.13 Å, 5.52 Å, 5.14 Å, 3.57 Å, 3.25 Å, 2.83 Å, 2.79 Å, 2.73 Å, 2.23 Å and 1.71 Å, each interplanar spacing value±0.04 Å.
摘要翻译:对应于通式(I)的多金属氧化物,其制备方法,含有此类氧化物的预催化剂和由其制备的催化剂用于烃的气相部分氧化:<?in-line-formula description =“In-line Formulas”end =“ 导线“>> Ag sub> C sub> C b> sub> 其中a表示数值为5〜9的数字,其中a表示0〜5的整数。 Q表示选自P,As,Sb,Bi及其混合物的元素; b表示数值为0.2〜3的数; M表示选自Li,Na,K,Rb,Cs,Tl,Mg,Ca,Sr,Ba,Cu,Zn,Cd,Pb,Cr,Au,Al,Fe,Co,Ni, Ce,Mn,Nb,W,Ta,Mo及其混合物; c表示小于1的数字; d表示数值,其数值由式(I)中Ag,Q,M和V的化合价和频率决定; e表示0〜20的数, 其中所述多金属氧化物具有晶体结构,其中其粉末X射线衍射图包括选自7.13,5.52,5.14,3.57,3.25,2.83,2.79,2.73的至少5个面间距的反射 Å,2.23Å和1.71Å,每个晶面间距值±0.04Å。
摘要:
A multimetal oxide of the formula I, Aga-cQbMcV2Od*eH2O, I where a is from 0.3 to 1.9, Q is an element selected from among P, As, Sb and/or Bi, is from 0 to 0.3, M is a metal selected from among Nb, Ce, W, Mn, Ta, Pd, Pt, Ru and/or Rh, c is from 0.001 to 0.5, with the proviso that (a-c)≧0.1, d is a number which is determined by the valence and abundance of the elements other than oxygen in the formula I and e is from 0 to 20, and also precatalysts and catalysts produced therefrom for the partial oxidation of aromatic hydrocarbons are described.
摘要翻译:式I的多金属氧化物,<?in-line-formula description =“In-line Formulas”end =“lead”?> Ag sub> ?V V V V V * O O O O O,,------------------------------------- 其中a为0.3〜1.9,Q为选自P,As,Sb和/或Bi的元素,为0〜0.3,M为选自Nb, Ce,W,Mn,Ta,Pd,Pt,Ru和/或Rh,c为0.001至0.5,条件是(ac)> = 0.1,d为由化合价 描述了式I中的氧以外的元素和e为0至20,并且还描述了由其制备的用于芳族烃的部分氧化的预催化剂和催化剂。
摘要:
Catalytic titanium dioxide mixtures comprising: a first anatase titanium dioxide having a BET surface area greater than 15 m2/g and a hydrogen uptake for the reduction of Ti4+ to Ti of from 5 to 20 μmol/m2; and a second anatase titanium dioxide having a BET surface area less than or equal to 15 m2/g and a hydrogen uptake for the reduction of Ti4+ to Ti3+ of from 0.6 to 7 μmol/m2, processes for preparing catalysts containing the same, catalysts containing active compositions including such titanium dioxide mixtures on support materials, and catalyst systems using the same.
摘要翻译:催化二氧化钛混合物,其包含:具有大于15m 2 / g的BET表面积的第一锐钛矿二氧化钛和将Ti 4+还原成Ti的氢吸收 为5至20mumol / m 2; 和具有小于或等于15m 2 / g的BET表面积的第二锐钛矿二氧化钛和用于还原Ti 4+的氢吸收 0.6〜7μmol/ m 2以上的3+以下,制备含有该催化剂的催化剂的方法,含有活性组合物的催化剂,包括载体材料上的这种二氧化钛混合物,以及使用 相同。
摘要:
A description is given of a process for preparing aldehydes, carboxylic acids and/or carboxylic anhydrides, in particular phthalic anhydride, in which a gaseous stream comprising an aromatic hydrocarbon and molecular oxygen is passed at elevated temperature over a bed of a first catalyst and a bed which is made up of a second catalyst having a higher activity than the first catalyst and is located downstream of the first catalyst in the flow direction of the gaseous stream, wherein the catalytically active composition of the first catalyst comprises at least vanadium oxide, titanium dioxide and antimony oxide and the ratio of vanadium, calculated as V2O5, to antimony, calculated as Sb2O3, in the first catalyst is from 3.5:1 to 5:1. The source of antimony oxide used for the first catalyst is preferably particulate antimony trioxide having a mean particle size of from 0.5 to 5 μm. The process allows the desired oxidation products to be obtained in high yield over longer periods of time.
摘要翻译:给出了制备醛,羧酸和/或羧酸酐,特别是邻苯二甲酸酐的方法的描述,其中包含芳族烃和分子氧的气流在升高的温度下通过第一催化剂的床和 床,其由比第一催化剂高的活性的第二催化剂组成,并且位于气流的流动方向上位于第一催化剂的下游,其中第一催化剂的催化活性组合物至少包含氧化钒,钛 二氧化锑和氧化锑,以V 2 O 5 5计算的钒与锑的比例计算为Sb 2 O 3 在第一催化剂中为3.5:1至5:1。 用于第一催化剂的氧化锑的来源优选是平均粒径为0.5-5微米的颗粒状三氧化锑。 该方法允许在较长时间内以高产率获得所需的氧化产物。
摘要:
Catalyst systems for preparing phthalic anhydride by means of gas-phase oxidation of o-xylene and/or naphthalene, and a process for preparing phthalic anhydride using the catalyst systems.
摘要:
Catalytic titanium dioxide mixtures comprising: a first anatase titanium dioxide having a BET surface area greater than 15 m2/g and a hydrogen uptake for the reduction of Ti4+ to Ti3+ of from 5 to 20 μmol/m2; and a second anatase titanium dioxide having a BET surface area less than or equal to 15 m2/g and a hydrogen uptake for the reduction of Ti4+ to Ti3+ of from 0.6 to 7 μmol/m2, processes for preparing catalysts containing the same, catalysts containing active compositions including such titanium dioxide mixtures on support materials, and catalyst systems using the same.
摘要翻译:催化二氧化钛混合物,其包含:BET表面积大于15m 2 / g的第一锐钛型二氧化钛和用于还原Ti 4+至Ti 3+的氢吸收为5至20μmol/ m 2; 和BET表面积小于或等于15m 2 / g的第二锐钛矿型二氧化钛和用于还原Ti 4+至Ti 3+的氢吸收为0.6〜7μmol/ m 2,制备含有该催化剂的催化剂,含有 包含载体材料上的这种二氧化钛混合物的活性组合物和使用其的催化剂体系。
摘要:
Catalyst systems for preparing phthalic anhydride by means of gas-phase oxidation of o-xylene and/or naphthalene, and a process for preparing phthalic anhydride using the catalyst systems.
摘要:
A process is described for producing a catalyst for gas-phase oxidations, in which a suspension of TiO2 and V2O5 particles is applied to a fluidized inert support, wherein at least 90% by volume of the V2O5 particles have a diameter of 20 μm or less and at least 95% by volume of the V2O5 particles have a diameter of 30 μm or less. The defined particle size distribution of the V2O5 allows a high coating efficiency.
摘要翻译:描述了一种制备用于气相氧化的催化剂的方法,其中将TiO 2和V 2 O 5颗粒的悬浮液施加到流化惰性载体上,其中至少90体积%的V 2 O 5颗粒的直径为20μm或更小 并且至少95体积%的V 2 O 5颗粒的直径为30μm或更小。 V2O5的定义的粒度分布允许高涂层效率。