Abstract: A process for the production of dialkyl carbonates from the reaction of alcohol, for example C1–C3 alcohols, with urea is disclosed wherein the water and ammonium carbamates impurities in the feed are removed in a prereactor. The water is reacted with urea in the feed to produce ammonium carbamate which is decomposed along with the ammonium carbamates originally in the feed to ammonia and carbon dioxide. In addition some of the urea is reacted with the alcohol in the first reactor to produce alkyl carbamate which is a precursor to dialkyl carbonate. Dialkyl carbonates are produced in the second reaction zone. The undesired by-product N-alkyl alkyl carbamates are continuously distilled off from the second reaction zone along with ammonia, alcohol and dialkyl carbonates under the steady state reactor operation. N-alkyl alkyl carbamates can be converted to heterocyclic compounds in a third reaction zone to remove as solids from the system.

Abstract: An improved selective hydrogenation process for removing acetylenic impurities such as vinyl acetylene, ethyl acetylene, propyl acetylene and acetylene in a steam cracked crude butadiene stream by selective hydrogenation is carried out in two steps. In the first step, the partial selective hydrogenation is carried out in a fixed bed with a copper based catalyst to have the ratio of vinyl acetylene to ethyl acetylene in a range of from 0 to about 1, preferably from about 0.01 to 0.6, in the product stream. In the second step, the selective hydrogenation of the remaining C4 acetylenic impurities is carried out to completion in the catalytic distillation mode using a palladium promoted copper catalyst, an improved palladium catalyst or a combination of these two.

Abstract: Improved Ni catalysts for hydrogenation reactions are disclosed. The catalysts are useful for hydrogenation such as selective hydrogenation of acetylenic impurities in crude olefin and diolefin streams. The catalysts are prepared by depositing nickel on a porous support which has the following specific physical properties; BET surface area of from 30 to about 100 m2/g, total nitrogen pore volume of from 0.4 to about 0.9 cc/g, and an average pore diameter of from about 110 to 450 ? with or without modifiers of one or more elements selected from the group consisting of Cu, Re, Pd, Zn, Mg, Mo, Ca and Bi.

Abstract: An improved selective hydrogenation process for removing acetylenic impurities such as vinyl acetylene, ethyl acetylene, propyl acetylene and acetylene in a steam cracked crude butadiene stream by selective hydrogenation is carried out in two steps. In the first step, the partial selective hydrogenation is carried out in a fixed bed with a copper based catalyst to have the ratio of vinyl acetylene to ethyl acetylene in a range of from 0 to about 1, preferably from about 0.01 to 0.6, in the product stream. In the second step, the selective hydrogenation of the remaining C4 acetylenic impurities is carried out to completion in the catalytic distillation mode using a palladium promoted copper catalyst, an improved palladium catalyst or a combination of these two.

Abstract: An improved selective hydrogenation process for removing acetylenic impurities such as vinyl acetylene, ethyl acetylene, propyl acetylene and acetylene in a steam cracked crude butadiene stream by selective hydrogenation is carried out in two steps. In the first step, the partial selective hydrogenation is carried out in a fixed bed with a copper based catalyst to have the ratio of vinyl acetylene to ethyl acetylene in a range of from 0 to about 1, preferably from about 0.01 to 0.6, in the product stream. In the second step, the selective hydrogenation of the remaining C4 acetylenic impurities is carried out to the completion in the catalytic distillation mode using a palladium promoted copper catalyst, an improved palladium catalyst or a combination of these two.

Abstract: An improved selective hydrogenation process for removing acetylenic impurities such as vinyl acetylene, ethyl acetylene, propyl acetylene and acetylene in a steam cracked crude butadiene stream by selective hydrogenation is carried out in two steps. In the first step, the partial selective hydrogenation is carried out in a fixed bed with a copper-based catalyst to have the ratio of vinyl acetylene to ethyl acetylene in a range of from 0 to about 1, preferably from about 0.01 to 0.6, in the product stream. In the second step, the selective hydrogenation of the remaining C4 acetylenic impurities is carried out to completion in the catalytic distillation mode using a palladium promoted copper catalyst, an improved palladium catalyst or a combination of these two.

Abstract: Acetylenic compounds in olefin streams such as mixed 1,3-butadiene were selectively hydrogenated over the supported copper catalysts on highly porous supports such as alumina, silica, etc. The preferred supports have the average pore diameter larger than about 200 Å, no micro pores, total pore volume larger than about 0.65 cc/g, and preferably less than about 230 m2/g BET surface area. The copper catalysts were preferably promoted with the Group VIII metal such as palladium to improve low activity of copper catalyst. The product stream typically contains less than 20 ppm total alkynes. Also the copper catalysts and the palladium promoted copper catalysts may be modified with zinc oxide to improve the performance of the catalysts. The reactor was loaded with two or more copper catalysts promoted with different levels of palladium.

Abstract: A process for removing acetylenic compounds using unsulfided metallic nickel or unsulfided metallic nickel modified with metallic Mo, Re, Bi or mixtures in which the catalyst is used alone or is used in combination with other acetylenic selective catalysts. The unsulfided metallic nickel catalyst or modified catalyst must be the first catalyst to contact the hydrocarbon stream.

Abstract: Carbonyl compound contaminants are removed from hydrocarbon streams containing olefins for use, for example, in the process for the skeletal isomerization of olefins by pretreating the hydrocarbon stream by passing it over an acidic catalyst at elevated temperatures in the range of 100-400° C. under conditions to react the carbonyls to form reaction products which are deposited onto the catalyst.

Abstract: Acetylenic compounds in olefin streams such as mixed 1,3-butadiene were selectively hydrogenated over the supported copper catalysts on highly porous supports such as alumina, silica, etc. The preferred supports have the average pore diameter larger than about 200 Å, no micro pores, total pore volume larger than about 0.65 cc/g, and preferably less than about 230 m2/g BET surface area. The copper catalysts were preferably promoted with the Group VIII metal such as palladium to improve low activity of copper catalyst. The product stream typically contains less than 20 ppm total alkynes. Also the copper catalysts and the palladium promoted copper catalysts may be modified with zinc oxide to improve the performance of the catalysts. The reactor was loaded with two or more copper catalysts promoted with different levels of palladium.

Abstract: Acetylenic compounds in olefin streams such as mixed 1,3-butadiene were selectively hydrogenated over the supported copper catalysts on highly porous supports such as alumina, silica, etc. The preferred supports have the average pore diameter larger than about 200 Å, no micro pores, total pore volume larger than about 0.65 cc/g, and preferably less than about 230 m2/g BET surface area. The copper catalysts were preferably promoted with the Group VIII metal such as palladium to improve low activity of copper catalyst. The product stream typically contains less than 20 ppm total alkynes. Also the copper catalysts and the palladium promoted copper catalysts may be modified with zinc oxide to improve the performance of the catalysts. The reactor was loaded with two or more copper catalysts promoted with different levels of palladium.

Abstract: An integrated process for upgrading a mixed C4 or mixed C5 alkane/isoalkane stream first separates the iso from the normal alkane by distillation. Then a portion of the normal alkane is dehydrogenated to the corresponding alkene. The isoalkane and normal alkene are then fed to an alkylation unit where they are reacted together to form a branched chain alkane having a desirable octane number. If desired a portion of the separated normal alkane may be skeletally isomerized to additional isoalkane.

Abstract: Acetylenic compounds in olefin streams such as mixed 1,3-butadiene were selectively hydrogenated over the supported copper catalysts on highly porous supports such as alumina, silica, etc. The preferred supports have the average pore diameter larger than about 200 Å, no micro pores, total pore volume larger than about 0.65 cc/g, and preferably less than about 230 m2/g BET surface area. The copper catalysts were preferably promoted with the Group VIII metal such as palladium to improve low activity of copper catalyst. The product stream typically contains less than 20 ppm total alkynes. Also the copper catalysts and the palladium promoted copper catalysts may be modified with zinc oxide to improve the performance of the catalysts. The reactor was loaded with two or more copper catalysts promoted with different levels of palladium.

Abstract: A process for producing dialkyl carbonates, such as dimethyl carbonate, from the reaction of a primary alcohol with urea in the presence of a catalyst which is a complex compound represented by R2Sn(OCH3)2·&khgr;L, wherein R=CnH2n+1, n=1 to 12, &khgr;=1 or 2, and L is oxygen atom containing organic complexing agent which is carried out by conducting the reaction continuously under reactive distillation conditions wherein the product DMC is stripped from the reaction mixture with methanol and further including the recovery of product dimethyl carbonate (DMC) made in the process by contacting a stream containing the DMC, such as a azeotropic mixture with methanol, with diethyl oxylate under conditions of extractive distillation to selectively separate the DMC from methanol.

Abstract: A process for producing dialkyl carbonates, such as dimethyl carbonate, from the reaction of a primary alcohol with urea in the presence of a catalyst which is a complex compound represented by R2Sn(OCH3)2.&khgr;L, wherein R=CnH2n+1, n=1 to 12, &khgr;=1 or 2, and L is oxygen atom containing organic complexing agent which is carried out by conducting the reaction continuously under reactive distillation conditions wherein the product DMC is stripped from the reaction mixture with methanol and further including the recovery of product dimethyl carbonate (DMC) made in the process by contacting a stream containing the DMC, such as a azeotropic mixture with methanol, with diethyl oxylate under conditions of extractive distillation to selectively separate the DMC from methanol.

Abstract: A novel catalyst, which is a complex of organotin with a high boiling electron donor compound acting as solvent which includes bidentate ligands which form 1:1 bidentate and/or 1:2 monodentate adducts with R'.sub.2 SnX.sub.2 (X=Cl, R'O, R'COO or R'COS), R'.sub.3 SnX, R'.sub.2 SnO, Ph.sub.3-n R'SnX.sub.n or Ph.sub.4-n SnX.sub.n (wherein R'=C.sub.q H.sub.2q-1 n=0, 1 or 2 and q=2 to 12) and mixtures thereof, such as materials having the general formula RO[CH.sub.2 (CH.sub.2).sub.k CH.sub.2 O].sub.m R, wherein each R is independently selected from C.sub.1-12 alkyl, alkaryl or aralkyl moieties, k=0, 1, 2 or 3 and m=1, 2, 3, 4 or 5. The catalyst is useful in the process for producing dialkyl carbonates, such as dimethyl carbonate, from the reaction of a primary alcohol with urea.

Abstract: Carbonyl compound contaminants are removed from hydrocarbon streams containing olefins for use, for example, in the process for the skeletal isomerization of olefins by pretreating the hydrocarbon stream by passing it over an acidic catalyst at elevated temperatures in the range of 100-400.degree. C. under conditions to react the carbonyls to form reaction products which are deposited onto the catalyst.

Abstract: A process for producing dialkyl carbonates, such as dimethyl carbonate, from the reaction of a primary alcohol with urea in the presence of a novel organotin catalyst complex with a high boiling electron donor compound acting as solvent which are (1) materials having the general formula RO?CH.sub.2 (CH.sub.2).sub.k CH.sub.2 O!.sub.m R, wherein each R is independently selected from C.sub.1-12 alkyl, alkaryl or aralkyl moieties, k=0,1, 2 or 3 and m=1, 2, 3, 4 or 5 and (2) bidentate ligand which form 1:1 bidentate and/or 1:2 monodentate adducts with R'.sub.2 SnX.sub.2 (X=Cl, R'O, R'COO or R'COS), R'.sub.3 SnX, R'SnO, Ph.sub.3-n R'SnX.sub.n or Ph.sub.4-n SnX.sub.n (wherein R'=C.sub.q H.sub.2q-1 n=0, 1 or 2 and q=2 to 12) and mixtures thereof.

Abstract: A isomerization process for C.sub.4 to C.sub.15 olefins carried out by the reaction of C.sub.4 to C.sub.15 olefins, having a first skeletal distribution, with aromatic compounds under alkylation conditions to produce an alkylated aromatic product, dealkylation of the alkylated aromatic product under dealkylation conditions to produce a dealkylated product comprising said aromatic compounds and olefins corresponding to the olefins in the alkylation and having a second skeletal distribution different than said first skeletal distribution. Acidic catalysts such as molecular sieves are used in both alkylation and dealkylation. The reactions may be carried out in either straight pass fixed beds or in catalytic distillation reactors.

Abstract: A process for producing dialkyl carbonates, such as dimethyl carbonate, from the reaction of a primary alcohol with urea in the presence of a novel organotin catalyst complex with a high boiling electron donor compound acting as solvent which are (1) materials having the general formula RO[CH2(CH2)kCH2O]mR, wherein each R is independently selected from C1-12 alkyl, alkaryl or aralkyl moieties, k=0,1, 2 or 3 and m=1, 2, 3, 4 or 5 and (2) bidentate ligand which form 1:1 bidentate and/or 1:2 monodentate adducts with R′2SnX2(X═Cl, R′O, R′COO or R′COS), R′3SnX, R′SnO, Ph3-nR′SnXn or Ph4-nSnXn (wherein R′=CqH2q-1n=0, 1 or 2 and q=2 1 to 12) and mixtures thereof, such as materials having the general formula RO[CH2(CH2)xCH2O]mR, wherein each R is independently selected from C1-12 alkyl, alkaryl or aralkyl moieties, k=0,1, 2 or 3 and m=1, 2, 3, 4, or 5.