Abstract: When steam cracking hydrocarbons to lower olefins in a tubular fired furnace having a convection section for preheating hydrocarbon feed, feedstock flexibility to process light feeds is provided by cooling mixed feed of steam and hydrocarbon followed by reheating to the desired mixed feed temperature.

Abstract: Triphenylphosphine oxide prevents fouling in ethylene furnaces.

Abstract: Methods for inhibiting coke formation in pyrolytic reactors and furnaces are disclosed wherein effective alkaline earth metal salt coke retardant treatments are used. Exemplary coke retardant treatments include magnesium and calcium salts such as the acetate, chloride, and nitrate, and magnesium sulfate salt.

Abstract: An improved method for reducing fouling and corrosion of ethylene cracking furnaces petroleum feedstocks, the improvement comprising treating the petroleum feed stock with at least 10 ppm of a combination of a phosphorous antifoulant compound and a filming inhibitor. The antifoulant compound is chosen from the group consisting of phosphite esters, phosphate esters, thiophosphite esters, thiophosphate esters and mixtures thereof, said esters being characterized by the formulas ##STR1## where X equals S or O, and R.sub.1, R.sub.2, and R.sub.3, are each independently selected from the group consisting of hydrogen, water soluble amine, alkyl, aryl, alkaryl, cycloalkyl, alkenyl, and aralkyl group provided that in at least one and not more than two of each R.sub.1, R.sub.2, and R.sub.3 are water soluble amines having partition coefficients greater than 1.0 mixed with a filming amount of at least 2-20 ppm imidazoline filming inhibitor prepared preferably from naphthenic or fatty acids and poly amines.

Abstract: Triphenylphosphine prevents fouling in ethylene furnaces.

Abstract: The present invention is concerned with a method of thermally decomposing a hydrocarbon and a thermal decomposition tube used therefor. A plurality of spiral fins are formed on the inner wall surface of the thermal decomposition tube. Since no-fin portions are formed on portions of the inner wall surface, the flow of a hydrocarbon through the no-fin portions is made turbulent to a suitable degree. For this reason, coke is prevented from adhering to the inner wall surface of the thermal decomposition tube.

Abstract: The invention relates to an improved hydrocarbon steam-cracking method intended to produce more particularly ethylene and propylene.The method is based on the utilization of a multi-channel system made of ceramic material, in which the charge and heat exchange fluids or refrigerants alternatively pass through the channels or rows of channels constituting the continuous assembly comprising a pyrolysis zone followed by a quenching zone.The method according to the invention is applicable to charges ranging from ethane to vacuum gas oils.

Abstract: The present invention relates to a process for the preparation of olefins and diolefins by the cracking of hydrocarbons in the presence of steam, consisting in passing a mixture of hydrocarbons and steam flowing in a cracking tube disposed inside a radiation zone of a furnace. The process is characterized in that the mean dwell time of the mixture of flowing in the cracking tube between the inlet and the outlet of the radiation zone is from 300 to 1800 milliseconds, and the reaction volume is greater in the first half of the tube length than in the second one. The present invention relates also to a cracking furnace in which the ratio between the length and the mean diameter of the cracking tube is from 200 to 600, and the tube diameter decreases from the inlet to the outlet of the radiation zone.

Abstract: A process for producing improved yields of aromatics (benzene, toluene, xylene) by initially partially thermally cracking heavy hydrocarbon and thermally cracking ethane to high conversion and then completely cracking the partially cracked heavy hydrocarbon with the completely cracked ethane.

Abstract: The present invention relates to a process for the preparation of olefins by the cracking of hydrocarbons consisting in passing a mixture of hydrocarbons and steam flowing in a cracking tube disposed inside a radiation zone of a furnace. The process is characterized in that an increase of the cracking temperature of the mixture between the inlet and the outlet of the radiation zone is associated to a non-homogeneous distribution of the thermal power of the furnace, greater at the beginning of the cracking tube than at the end, and to a reaction volume which is greater in the second half of the length tube than in the first one.The present invention relates also to a cracking furnace in which between the inlet and the outlet of the radiation zone the diameter of the cracking tube increases and the thermal power of the heating means decreases.

Abstract: The invention relates to a process for converting light hydrocarbon feedstocks such as methane and/or natural gas, to higher molecular weight hydrocarbon products that are more readily handleable and transportable. The process comprises heating a gaseous mixture comprising said light hydrocarbon feedstocks and carbon dioxide at a temperature of at least about 600.degree. C. for a period of time effective to provide said higher molecular weight liquid hydrocarbon product. The invention also relates to the higher molecular weight liquid products obtained by the process of the invention.

Abstract: A process for the selective production of petrochemical products by thermal cracking is disclosed. The process includes feeding methanol to a thermal cracking atmosphere of hydrocarbons in such a way that the ratio, as carbon atoms, of methanol and at least one starting hydrocarbon is at least 0.05:1, thermally cracking the at least one starting hydrocarbon at a cracking temperature of from 650.degree. to 1300.degree. C., and quenching the resulting reaction product.

Abstract: The invention relates to a process for converting light hydrocarbon feedstocks such as methane, ethane and/or natural gas, to higher molecular weight hydrocarbon products that are more readily handleable and transportable. The process comprises heating a gaseous mixture comprising said light hydrocarbon feedstocks and at least one oxide initiator selected from the group consisting of nitrogen oxides, sulfur trioxide and mixtures thereof at a temperature of at least about 600.degree. C. for a period of time effective to provide said higher molecular weight hydrocarbon product. In one embodiment, the invention provides for a process for converting the feedstocks, to unsaturated compounds such as ethylene. The invention also relates to the higher molecular weight products obtained by the process of the invention.

Abstract: An ethane-rich stream is reduced in pressure below the inlet pressure to a pyrolysis furnace, vaporized in heat exchange relationship with a process stream, recompressed, and passed to the pyrolysis furnace.

Abstract: Specified sulfur compounds such as N,N-diethylthiourea, N,N-dibutylthiourea, tetramethylthiuram monosulfide, tetrabutylthiuram monosulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide are supplied as a coking inhibitor for preventing coking in equipment used in hydrocarbon treatment processes wherein a hydrocarbon is treated at a temperature of from about 250.degree. C. to 950.degree. C. to produce petroleum products, petrochemical products and/or their intermediate products.

Abstract: The process for the interconversion of "small olefins" selected from the class consisting of ethylene, propylene, butenes and mixtures thereof comprising contacting said small olefin(s) with non-zeolitic molecular sieves.

Abstract: In this process ethylene is prepared by pyrolytically cracking ethane in a pyrolytic cracking furnace having a plurality of elongated serpentine-situated thermal cracking tubes which have a longer run life as a result of the selective cracking of a C.sub.3 to C.sub.12 hydrocarbonaceous material at conditions sufficient to selectively place a coat of amorphous relatively smooth coat of coke on the interior walls of the thermal cracking tubes and thereby mask the catalytic effect of iron, nickel, both iron and nickel, or other metal catalytic sites indigenous to the walls of the furnished tubes. In this manner, the amount of cracking time realized for each particular furnace before regeneration of the same is increased by 20 to 50%.

Abstract: A method for thermally cracking hydrocarbons under elevated pressure is disclosed.

Abstract: An improved method of reducing fouling and corrosion in ethylene cracking furnaces using petroleum feedstocks, the improvement comprising treating the petroleum feedstock with at least 10 ppm of a compound chosen from the group consisting of phosphite esters, phosphate esters, thiophosphite esters, thiophosphate esters and mixtures thereof, said esters being characterized by the formulas: ##STR1## where X equals S or O, and R.sub.1, R.sub.2, and R.sub.3, are each independently selected from the group consisting of hydrogen, water soluble amine, alkyl, aryl, alkaryl, cycloalkyl, alkenyl, and aralkyl group provided that in at least one and not more than two of each R.sub.1, R.sub.2, and R.sub.3 are water soluble amines having partition coefficients greater than 1.0.

Abstract: The heat provided to a cracking furnace is manipulated so as to maintain the actual conversion of a first component in the feed stream flowing to the cracking furnace substantially equal to the desired conversion for the first component. The actual conversion of the first component is determined based on an analysis for the concentration of the first component in the feed stream flowing to the cracking furnace, an analysis of the concentration of the first component in the product stream flowing from the cracking furnace, an estimate of the conversion of the first component and a calculation of the expansion of the feed stream in the cracking furnace. The thus derived actual conversion is compared to a desired conversion with the results of the comparison being utilized in combination with the feed flow rate to manipulate the heat provided to the cracking furnace.

Abstract: A thermal cracking method for producing olefins from hydrocarbons which comprises the steps of mixing said hydrocarbons with a mixed gas of methane and hydrogen in a methane/hydrogen mol ratio of 0.2 or more; prior to reaction carrying out a thermal cracking reaction under conditions such that the total concentration of methane and hydrogen is at least 40 mol % or more at the outlet of a reactor, the partial pressure of said hydrogen is 3 bars or more, the temperature at the outlet of the reactor is from 800.degree. to 1200.degree. C., and the residence time in the reactor is from 5 to 300 milliseconds; and quenching the reaction product discharged through the outlet of the reactor.

Abstract: The flow of cracked gases, for example, from an ethylene plant through the tubes of a transfer line heat exchanger is equalized by employing larger cross-section tubes in the outer portion of the exchanger and smaller cross-section tubes in the inner portion of the exchanger thereby preventing, or substantially minimizing, build-up of coke deposits in the exchanger, especially in the inlets of the tubes in the outer portion where coke formation conventionally occurs.

Abstract: Prequenching a conversion zone effluent by direct introduction and heat exchange with a convertable material. The thus quenched effluent passes through a transfer line heat exchange zone with considerably lessened deposition of carbonaceous materials. In one embodiment, liquid ethane and/or propane is injected with the use of a nozzle into the effluent of an ethylene production.

Abstract: The heat supplied to an ethylene process cracking furnace is manipulated so as to maintain a desired ethylene production rate while the flow of feed to the ethylene process cracking furnace is manipulated so as to substantially maximize the selectivity of the ethylene process cracking furnace to the production of ethylene. In this manner a desired ethylene production rate is maintained while the process economics are improved in the case where the cost of the feed is a more important economic consideration than the cost of the energy required for the cracking furnace by substantially minimizing the conversion of the feed to undesired byproducts.

Abstract: For thermally cracking heavy liquid hydrocarbons to produce gaseous olefins comprising a catalytic hydrogenating pretreatment, a separation of the hydrogenation product into a lighter fraction and a heavier fraction; passing the heavier fraction at least in part to a thermal cracking step to produce normally gaseous olefins; and withdrawing the lighter fraction, the improvement wherein the hydrogenation is conducted within the shaded area of FIG. 2, whereby said lighter fraction has a higher octane number.

Abstract: The heat provided to a cracking furnace is manipulated so as to substantially maximize the value of the product stream flowing from the cracking furnace. An analysis of the product stream may be utilized to measure the ratio of a first constituent in the product stream to a second constituent in the product stream (severity equivalent). The severity equivalent required to substantially maximize the value of the product stream may be calculated in response to process operating conditions. The heat supplied to the cracking furnace is manipulated in response to a comparison of the actual severity equivalent to the desired severity equivalent to thereby substantially maximize the value of the product stream.

Abstract: Hydrocarbons are subjected to hydrogenation, pressure reduction and separation into liquid and gaseous fractions. The gaseous fractions are purified and desulfurized. Hydrogen-rich components of the gaseous fraction are returned to the hydrogenation stage. Hydrocarbon-rich components of the gaseous fraction and components of the liquid fraction are cracked and fractionated. Residue is partially oxidized with oxygen and steam. Gas produced by the partial oxidation is desulfurized and separated, and hydrogen is returned to the hydrogenation stage. A polymer free fraction of the residue is returned to the feed stock and to the hydrogenation stage, a heavy residue component of the initial liquid fraction is partially oxidized with the residue.

Abstract: A process and system for sequentially cracking hydrocarbons in a TRC system. A first hydrocarbon feed is cracked at high severity low residence times and the cracked effluent is quenched by a second hydrocarbon feed which is coincidentally cracked at low severity.

Abstract: The invention relates to a process for making ethylene by subjecting a gas mixture containing hydrocarbons, hydrogen, carbon monoxide, carbon dioxide and steam to a hydropyrolysis reaction. More particularly, the gas mixture is heated to temperatures higher than 800.degree. C. inside a reaction zone having metal walls. The walls contain aluminum and/or copper in at least their surface portions.

Abstract: A process and system for sequentially cracking hydrocarbon. A first hydrocarbon feed is cracked at high severity low residence times and the cracked effluent is quenched by a second hydrocarbon feed which is coincidentally cracked at low severity.

Abstract: The invention is a method of handling the enthalpy of reaction of fast homogeneous gas-phase chemical reactions, by using mechanical energy in the form of work performed by moving surfaces in contact with the reactants, for adding energy to or removing energy from the gaseous reactants. Transfer of energy is obtained by adiabatic compression or expansion of the gas, or by adiabatic dissipation of mechanical energy into heat. The invention further relates to an apparatus for carrying out fast homogeneous gas phase chemical reactions wherein the said principles are applied in the reactor and to a process for cracking hydrocarbons wherein the said principle is applied in the reactor.

Abstract: A process for producing olefines by using a fluidized bed of coke particles rovided in each of a reactor and a heater, circulating coke particles through the reactor and the heater, heating the coke particles by a combustion of fuel and if desired, a part of the coke particles in the heater, thermally cracking a heavy oil with a heated coke particles as a heat carrier in the reactor, the improvement which comprises a distillation residue is converted into a high-temperature, low-calorie gas in a combustion chamber, and the coke particles is heated with the gas in the heater, further an increment of coke deposited on a surface of the coke particles is burned by blowing air to the heater.

Abstract: A method of producing high yields of olefins from hydrocarbon feedstocks which is particularly applicable to heavy hydrocarbons. In accordance with the present method, a stream of gaseous oxygen is introduced into a first reaction zone and a cocurrent flow of hydrogen is introduced about the periphery of the gaseous oxygen stream, the hydrogen being introduced at a temperature at which it will spontaneously react with the oxygen. The hydrogen and oxygen are introduced in amounts to provide a gas stream of reaction products having an average temperature within the range of from about 1,000.degree. to 2,000.degree. C. and which comprises a major amount of hydrogen and a minor amount of water vapor. The gas stream so produced is introduced into a second reaction zone and impinged upon a stream of hydrocarbon which is heated to a temperature in excess of its melting point but below the temperature at which any substantial coke or tar forms.

Abstract: A petroleum distillate feed is upgraded and a substantial C.sub.3 -C.sub.4 olefin product fraction produced by contacting the feed with ZSM-5 type zeolite at (1) a temperature in the 500.degree.-800.degree. F. range, (2) a pressure below about 13 atmospheres gauge, and (3) an LHSV in the 0.1-15 V/V/Hr range, and fractionating the effluent product stream.

Abstract: The process relates to the production of olefins by thermal cracking, in the absence of a catalyst, of a fuel value residual hydrocarbon feedstock which, prior to cracking, is extracted with a paraffinic solvent which is selective for the saturated hydrocarbon material present in the feedstock. Preferred extraction conditions include the use of supercritical temperatures and pressures. The solvent is separated from the extracted hydrocarbon material and the latter is then cracked.

Abstract: A process is disclosed for separating ethylene in admixture with light olefins by contacting said olefinic mixture under very critical reaction conditions over a special catalyst, such as a zeolite of the ZSM-5 type so as to selectively react the C.sub.3 and higher olefins and convert the same to both gasoline and fuel oil.

Abstract: Ethylene and maximum benzene are co-produced via a combination process involving (1) thermal cracking, or pyrolysis, (2) aromatic hydrocarbon separation, or extraction, and, (3) dealkylation of alkyl-substituted aromatics to yield additional benzene. Unconverted feed paraffins are recycled to thermal cracking for additional ethylene and benzene production.

Abstract: Unsaturated C.sub.4 hydrocarbons are converted into normal butane by introducing an unsaturated C.sub.4 hydrocarbon stream into a hydrogenation zone to convert it into a stream of normal butane and isobutane. Normal butane is recovered from a separation zone while isobutane is directed to an isomerization zone wherein a portion of the isobutane is converted into normal butane. The stream from the isomerization zone is returned to the separation zone to recover the normal butane produced in the isomerization reaction. The normal butane produced by the process is subsequently utilized in a cracking zone to produce ethylene.

Abstract: A catalytically hydrogenated naphtha stream containing less than 10 ppm by weight of sulfur is pyrolyzed without added hydrogen to a product including ethylene. Selectivity to ethylene is increased by adding a sulfur compound to increase the sulfur content to above 20 ppm by weight based on hydrogenated naphtha. Addition of the sulfur compound increases the quality of hydrogenated naphtha as a pyrolysis feedstock nearly to that of a C.sub.2 to C.sub.5 paraffin stream.

Abstract: Ethylene and maximum benzene are co-produced via a combination process involving (1) thermal cracking, or pyrolysis, (2) aromatic hydrocarbon separation, or extraction, and, (3) dealkylation of alkyl-substituted aromatics to yield additional benzene. Unconverted feed paraffins are recycled to thermal cracking for additional ethylene and benzene production.

Abstract: A continuous process for the selective production of ethylene by the diacritic cracking of heavy hydrocarbon feeds such as residual oils, heavy vacuum gas oils, atmospheric gas oils, crude oils and coal-derived liquids. The diacritic cracking takes place in a non-tubular multi-zone reactor at elevated pressures (e.g. 70-1000 p.s.i.a.) A fuel is combusted with oxygen in the first section of the multi-zone reactor. The high temperature products of combustion of the first zone pass into a second section of the reactor where the feed is atomized and cracked to yield products including ethylene, acetylene and synthesis gas. The reaction products of the second zone then pass into a third section in which they are quenched. In each stage of the reactor the present process seeks to prevent the build-up of coke deposits on the walls of the reactor. In the first two stages, a film of gas such as CO.sub.2 or N.sub.2 is injected along the inner walls to prevent build-up of coke.