摘要:
Processes for producing butadiene from n-butane comprising: (a) providing a feed gas stream comprising n-butane; (b) non-oxidatively dehydrogenating the feed gas stream in the presence of a catalyst in a first dehydrogenation zone to form a first intermediate gas stream comprising n-butane, 1-butene, 2-butene, butadiene and hydrogen; (c) oxidatively dehydrogenating the first intermediate gas stream in the presence of an oxygenous gas having an oxygen content of at least 75% by volume in a second dehydrogenation zone to form a second intermediate gas stream comprising n-butane, butadiene, hydrogen, carbon dioxide and steam; (d) compressing and cooling the second intermediate gas to form a first condensate stream comprising water and a third intermediate gas stream comprising n-butane, butadiene, hydrogen, carbon dioxide and steam; (e) compressing and cooling the third intermediate gas to form a second condensate stream comprising n-butane, butadiene and water and a fourth intermediate gas stream comprising n-butane, butadiene, hydrogen and carbon dioxide; (f) cooling the fourth intermediate gas stream to form a third condensate stream comprising n-butane and butadiene, and an offgas stream comprising carbon dioxide and hydrogen; (g) removing water from the second condensate stream and combining the second condensate stream and third condensate stream to form a C4 hydrocarbon stream comprising n-butane and butadiene; and (h) separating the C4 hydrocarbon stream to form a recycle stream comprising n-butane and a product stream comprising butadiene; wherein at least a portion of the recycle stream is fed to the first dehydrogenation zone.
摘要:
A process for preparing a vanadium, phosphorus, and oxygen catalyst precursor for preparing maleic anhydride by heterogeneously catalyzed gas-phase oxidation of a hydrocarbon having at least four carbon atoms, by reacting vanadium pentoxide (I) in the presence of a primary or secondary, noncyclic or cyclic, unbranched or branched, saturated alcohol having from 3 to 6 carbon atoms (II) with a pentavalent or trivalent phosphorus compound (III) in a temperature range from 80 to 160° C. with stirring and subsequently filtering the resultant suspension, in which (a) the way in which the phosphorus compound (III) and the vanadium pentoxide (I) are combined in the presence of the alcohol (II), (b) the action of a stirring power of from 0.01 to 0.6 W/kg suspension, and/or (c) the filtration at a temperature from 65° C. to 160° C. are used to set a filtration resistance αH·η of
摘要:
A method of charging a vertical tube having an internal diameter of 50 mm or less with catalyst particles, which comprises introducing a filling aid into the vertical tube, where the filling aid comprises a flexible elongated body and the ratio of the cross section of the flexible elongated body to the cross section of the tube is from 0.003 to 0.08, and introducing the catalyst particles into the tube.
摘要:
Disclosed is a method for producing a catalyst containing vanadium, phosphorus, and oxygen, which is used for oxidizing the gas phase of a hydrocarbon having at least four carbon atoms to maleic anhydride. According to the inventive method, a corresponding catalyst precursor which contains vanadium, phosphorus, and oxygen and is provided with particles having an average diameter of at least 2 mm is converted into a catalytically active form by means of calcination, and a flow of the catalyst precursor is transported on a conveyor belt across at least one calcination area over a distance 1n at an essentially steady speed in order to be calcinated. The variation over time of the gas temperature in relation to the set point value amounts to ≦5° C. at each position in the area of the flow of the catalyst precursor, which lies within the second half 1n/2 of the calcination area, while the local difference in the gas temperature between any positions in the area of the flow of the catalyst precursor, which is located within the second half 1n/2 of the calcination area, amounts to ≦5° C.
摘要:
A process for the electrochemical oxidation of organic compounds, wherein the anode material used is a mixed oxide of formula (I) MoaBibX1cX2dX3eX4fX5gOh (I) where X1 is V, Nb, Cr, W, Ta, Ga, Ce, and/or La; X2 is Li, La, K, Rb, Cs, Cu, Ag, Au, Pd and/or Pt; X3 is Fe, Co, Ni and/or Zn; X4 is Sn, Rb, Sb and/or Te; X5 is Ti, Zr, Si and/or Al; and where a is 0-3; b is 0-3; c is 0-12.5; d is 0-5; e is 0-1.5; f is 0-1; and g is 0-25 with the proviso that a+d≧0.15.
摘要:
A process for preparing butadiene, comprising A) providing a stream (a) comprising n-butane; B) feeding stream (a) comprising into at least one first dehydrogenation zone and nonoxidatively catalytically dehydrogenating n-butane to obtain a stream (b) comprising n-butane, 1-butene, 2-butene, butadiene, hydrogen and low-boiling secondary constituents; C) feeding stream (b) and an oxygenous gas into at least one second dehydrogenation zone and oxidatively dehydrogenating n-butane, 1-butene and 2-butene to obtain a stream (c) comprising n-butane, 2-butene, butadiene, low-boiling secondary constituents, carbon oxides and steam, wherein stream (c) has a higher content of butadiene than stream (b); D) removing the low-boiling secondary constituents and steam to obtain a stream (d) substantially consisting of n-butane, 2-butene and butadiene; E) separating stream (d) into a stream (e1) consisting substantially of n-butane and 2-butene and a stream (e2) consisting substantially of butadiene by extractive distillation; F) recycling stream (e1) into the first dehydrogenation zone.
摘要:
A process for preparing butadiene, comprising nonoxidatively dehydrogenating n-butane from a stream (a) in a first dehydrogenation zone to obtain stream (b) comprising 1-butene, 2-butene, and butadiene; oxidatively dehydrogenating the 1-butene and 2-butene of (b) in the presence of an oxygenous gas in a second dehydrogenation zone to obtain stream (c) comprising n-butane, butadiene, hydrogen, and steam; compressing and cooling (c) to obtain stream (d2) comprising n-butane, butadiene, hydrogen, and steam; extractively distilling (d2) into stream (e1) comprising butadiene and stream (e2) comprising n-butane, hydrogen, and steam; optionally compressing and cooling (e2) to obtain stream (f1) comprising n-butane and water and stream (f2) comprising n-butane and hydrogen and optionally recycling (f1) into the first dehydrogenation zone; separating (f2) into stream (g1) comprising n-butane and stream (g2) comprising hydrogen by contacting (f2) with a high boiling absorbent and subsequently desorbing the gas constituents dissolved in the absorbent.
摘要:
The disclosure involves a process for the preparation of butadiene and 1-butene. The process includes at least a first catalytic dehydrogenation of n-butane to obtain a gas stream which is followed by at least a second oxidative dehydrogenation to form a second gas stream. The second gas stream is then subjected to distillation and isomeration steps to obtain butadiene and 1-butene.
摘要:
A process for coating internals in a reactor, except for the coating of electrically heatable, at least partly open-cell foams, with a catalytically active material or a precursor thereof is described, in which an aerosol which contains, as a disperse phase, the catalytically active material or the precursor thereof is provided and the aerosol is passed through the reactor at a velocity which is established so that the disperse phase of the aerosol is deposited on the internals in the reactor.
摘要:
The invention relates to a method for oxidizing substrates such as hydrocarbons, waxes or soot. The method involves the use of a compound of formula (I) in which: R1 and R2 represent H, an aliphatic or aromatic alkoxy radical, carboxyl radical, alkoxycarbonyl radical or hydrocarbon radical, each having 1 to 20 hydrocarbon atoms, SO3H, NH2, OH, F, Cl, Br, I and/or NO2, whereby R1 and R2 designate identical or different radicals or R1 and R2 can be linked to one another via a covalent bonding; Q1 and Q2 represent C, CH, N, CR5, each being the same or different; X and Z represent C, S, CH2, each being the same or different; Y represents O and OH; k=0, 1, 2; l=0, 1, 2; m=1 to 3, and; R5 represents one of the meanings of R1. Said compound is used as a catalyst in the presence of a radical initiator, whereby the molar ratio of the catalyst to the hydrocarbon is less than 10 mol %. Peroxy compounds or azo compounds can be used as the radical initiator. Preferred substrates are aliphatic or aromatic hydrocarbons.
摘要翻译:本发明涉及一种氧化底物例如烃,蜡或烟灰的方法。 该方法包括使用式(I)化合物,其中:R 1和R 2表示H,脂族或芳族烷氧基,羧基,烷氧基羰基或烃基,各自具有1至20个烃基,SO 3 H,NH 2, OH,F,Cl,Br,I和/或NO 2,其中R 1和R 2表示相同或不同的基团,或者R 1和R 2可以通过共价键彼此连接; Q1和Q2表示C,CH,N,CR5,各自相同或不同; X和Z表示C,S,CH 2,各自相同或不同; Y表示O和OH; k = 0,1,2; l = 0,1,2; m = 1〜3, R5表示R1的含义之一。 所述化合物在自由基引发剂存在下用作催化剂,其中催化剂与烃的摩尔比小于10mol%。 过氧化合物或偶氮化合物可用作自由基引发剂。 优选的底物是脂族或芳族烃。