Use of a catalyst with phosphate carrier in the conversion of alcohols into hydrocarbons

Abstract: A catalyst for the conversion of lower aliphatic alcohols such as methanol to form petroleum type hydrocarbons comprises one or more metals and/or metal ions supported on a phosphate carrier. Preferred metals include transition metals such as Ti, Ni, Cu, Zn, Rh, Ag, Ir and alkali metals, alkaline earth metals, Al and Sn. The phosphate carrier is preferably aluminium phosphate, zirconyl phosphate, magnesium phosphate, barium phosphate, zinc phosphate or a calcium phosphate compound. The metal should amount to 0.1 to 30 % by weight with respect to the phosphate carrier. This catalyst is used to convert by contact cracking lower aliphatic alcohols to produce the gasoline type hydrocarbons at a reaction temperature of 200° to 600°C and a supply rate of 0.75 to 3.0 weight units of alcohol per weight unit of catalyst per hour.

Description: Technical Field The invention relates to the use of a phosphate based catalyst in the contact cracking of lower alkanols and to a method for the contact cracking of lower alkanols, in which method the phosphate based catalyst is used. Prior Art Because petroleum has become expensive, it is now of interest to produce petroleum products (such as gasoline, kerosene and light and heavy oils) from other hydrocarbon materials such as coal and natural gas. The MTG method developed by Mobile Co. enables a mixture of aromatic hydrocarbons having less than 10 carbon atoms, olefin hydrocarbons and paraffin hydrocarbons to be produced from methanol in the presence of ZSM-5 zeolite having a specific pore structure as a catalyst at a temperature of from 250°C to 450°C. The disadvantages of this method lie in the ZSM-5 catalyst, which is expensive and time consuming to make due to the long time needed for crystallization, is not easily made to a reproducible standard, and quickly loses its effectiveness due to the accumulation of solids in the MTG reaction. EP 0141662 provides an alternative catalyst for MTG (methanol to gasoline) conversion, consisting of a microporous crystalline aluminophosphate in which a proportion of the aluminium ions have been substituted by divalent atoms such as Mg, Zn, Mn, Co, Ni and Fe and a proportion of the phosphate ions have been substituted by tetravalent atoms such as Ge, Sn, Ti and Si. Typically these catalysts give a conversion product from methanol which contains from 25 to 55% of liquid hydrocarbons, with at least 35% of the product remaining gaseous and up to 30% of solids. An alternative catalyst is sought. The Invention The invention provides a method for the preparation of petroleum type hydrocarbons, the method comprising contacting an alkanol, alkanediol, polyol or hydrated alcohol having from 1 to 4 carbon atoms with a catalyst at from 200 to 600°C, the supply rate per hour of the alkanol, alkanediol, polyol or hydrated alcohol being up to 15 times the weight of catalyst, wherein the catalyst comprises one or more metals and/or metal ions selected from Ti, Mn, Fe, Co, Ni, Cu, Pt, Ir, Rh, Ag, the alkali metals, the alkaline earth metals, Zn, Al and Sn supported on a carrier of zirconyl phosphate, magnesium phosphate, barium phosphate, zinc phosphate or a calcium phosphate compound, or a mixture of two or more thereof, the content of metal and/or metal ion being from 0.1 to 30% by weight with respect to the carrier. The preferred calcium phosphate compounds for use as the carrier are hydroxyapatite, calcium tertiary phosphate, calcium primary phosphate, calcium secondary phosphate, calcium pyrophosphate, calcium metaphosphate, fluoroapatite, calcium quarternary phosphate and calcium octaphosphate. Such phosphate compounds, which may be non-stoichiometric, provide the multifunctional properties to the catalyst, because they have the acidic and basic functional properties and ion exchange property, in which the relatively weak acidic and basic points act together. The preferred metals/metal ions to be included in catalysts for use in the invention include Ti, Ni, Cu, Zn, Rh, Ag, Ir, Pt, Mg, Ca, Ba, Al and Sn. The amount of metal and/or metal ions to be supported on the carrier will generally depend upon the nature of the metal(s) and of the carrier. Too high a proportion of metal and/or metal ion, however, may reduce the catalytic activity, so the amount of metal and/or metal ion should be from 0.1 to 30% by weight with respect to the carrier. The catalysts for use in the invention may be prepared by methods known per se, such as the ion exchanging method, the permeability method and the physical mixing method. The catalysts can also be obtained by synthesizing the phosphate carrier in the presence of one or more of the metals and/or ions to be supported on it. For instance, a solution of one or more salts of the aforesaid metals is added (or two or more solutions, each of a salt of a different one of the aforesaid metals, are successively added) to a solution or suspension of the phosphate carrier, and stirred to ensure full dispersion. The temperature can be from room temperature to boiling point. The pH is adjusted, if necessary, and the precipitate is collected. Uniform dispersion may be aided by adding agents such as the salts of phosphoric, nitric and hydrochloric acids to the aqueous solution or suspension. It is desirable that the reaction time is from one or several hours when the reaction mixture is heated or from one or several days when the reaction temperature is low, e.g. room temperature. The precipitate obtained is washed with water, dried and powdered. It may be heat fired. Drying is preferably effected at a temperature of more than 100°C, preferably 200°C to 400°C, for 1 to 24 hours. The catalysts can be used in the invention in the form of powders, as granulates produced by spray drying of suspension, and in honey comb states and raschig ring states produced by pressure and injection molding. Thus various physical forms are suitable, but it is generally desirable to use the catalyst after heat firing at a temperature of 1400°C or less. Other activation processes such as heat treatment in inert gas or reduction treatment in a reducing atmosphere can be used. The catalytic activity can be improved by these treatments and the catalytic properties can be adjusted to suit the nature of the lower aliphatic alcohols to be contact cracked. When a metal salt is deposited on the carrier, and heated to form a catalyst for use in the invention, the salt will decompose depending upon the atmosphere, temperature and heating time. If the metal of the metal salt is one which has an oxide which is thermally unstable in air, such as Pt or Ag, and the heating temperature in air is less than the decomposition temperature, the metal is carried on the carrier as the metal ion; when the heating temperature in air is more than the decomposition temperature, the metal is carried on the carrier as the metal. In air, salts of metals having thermally stable oxides are converted to the metal oxides by the heating process. In inert gases or reducing gases such as hydrogen, however, the metal oxides will be converted first to metal ions, then to a combination of metal ions and metals, and finally to metals only at a low temperature in the range of 100 to 400°C according to the heating time. As a result catalysts carrying metal ions, a combination of metal ions and metals, or metals only may be obtained by adjustment of the temperature and the time as mentioned above. It is noted that, in the application of this process to the production of a catalyst according to the invention, the conversion rate varies depending upon the type of metal oxide, the temperature and the heating time. In the case of full conversion to the metal, the catalytic activity is lowered. The conversion rate may be chosen so as to avoid this. The method of the invention can be performed in various gas atmospheres, for example in nitrogen, hydrogen, CO 2 , argon or helium. Also, the reaction can be carried out by various means, such as a fixed bed process, a moving bed process or a fluidized bed process. The fixed bed process is easy to operate, and so is preferred. The reaction temperature may vary according to the lower aliphatic alcohol to be cracked. However, the yield of gasoline type hydrocarbons is decreased when the reaction temperature is low and the deterioration of catalytic activity is accelerated by forming the cokes, and the regeneration of catalyst is increased when the reaction temperature is high, so it is desirable to use a reaction temperature from 200°C to 600°C. WHSV (Weight Hourly Space Velocity), by which the supply speed of the material, lower aliphatic alcohol, per gram of the catalyst is shown (g·methanol/g·catalyst·hr), is not particularly limited, however 15 or less is desirable to obtain a high conversion rate. Particularly, the range from 0.75 to 3.0 is desirable. The catalysts for use in the invention are easily prepared at a low price. Gasoline type hydrocarbons can be obtained from lower alkanols in high yield. Preferred Embodiments Example 1 200 g of zirconyl phosphate was suspended under stirring in 2 l of ion exchanged water. 20 g of copper nitrate in aqueous solution and 27 g of zinc nitrate, also in aqueous solution, were added to this suspension and stirred for 3 days. The solids were then recovered, washed with water and dried at 200°C to give a powdered catalyst composition containing 2.5 % copper and a 2.0 % zinc. Example 2 200 g of barium phosphate was suspended under stirring in 2 l of ion exchanged water. 3.5 g of chloroplatinic acid in aqueous solution, 3.0 g of silver nitrate in aqueous solution and 13 g of aluminium nitrate in aqueous solution were added to this suspension and stirred for 1 day. The solids were then recovered, washed with water and dried at 150°C to give a powdered catalyst composition containing 0.5 % platinum, 0.5 % silver and 0.3 % aluminium. Example 3 200 g of magnesium phosphate was added to 2 l of ion exchanged water, and the whole was stirred and heated to 85°C to obtain a suspension. 6.5 g of tin chloride in aqueous solution and 30 g of titanium sulphate, also in aqueous solution, were successively added to the suspension, while keeping the temperature at 85°C. Stirring was continued for 8 hours at 85°C, following which the solids were recovered, washed with water and dried at 400°C. A powdered catalyst composition containing 1.9 % tin and 2.6 % titanium was obtained. Example 4 200 g of zinc phosphate was suspended under stirring in 2 l of ion exchanged water. To the suspension there were successively added aqueous solutions containing 19 g of barium nitrate, 15 g of iridium (II) chloride, 35 g of rhodium (III) sulphate, 45 g of calcium nitrate, 150 g of magnesium sulphate and 25 g of silver nitrate. Stirring was continued for 4 days. The solids were then recovered, washed with water and dried at 150°C to give a powdered catalyst composition containing 4 % of barium, 4.5 % of iridium, 4.5 % of rhodium, 3.0 % of calcium, 7.0 % of magnesium and 6.5 % of silver. Example 5 200 g of magnesium phosphate was suspended under stirring in 3 l of ion exchanged water. 15 g of nickel nitrate in aqueous solution and 18 g of zinc nitrate, also in aqueous solution, were added to the suspension and stirred for 5 days. The solids were recovered, washed with water and dried at 200°C to give a powdered catalyst composition containing 1.3 % of nickel and 1.5 % zinc. Example 6 300 g of calcium tertiary phosphate was suspended under stirring in 2 l of ion exchanged water. An aqueous solution containing 0.6 g of silver nitrate was added to the suspension and the mixture stirred for 2 days. The solids were recovered, washed with water and dried at 350°C to give a powdered catalyst composition containing 0.1 % of silver. Example 7 200 g of calcium tertiary phosphate was suspended in 2 l of ion exchanged water under stirring. 20 g of copper nitrate in aqueous solution and 27 g of zinc nitrate, also in aqueous solution, were successively added to the suspension. Stirring was continued for 4 days, and the solids were then recovered. After washing with water and drying at 200°C, a powdered catalyst composition containing 2.5 % of copper and 2 % of zinc was obtained. Example 8 200 g of hydroxyapatite was added to 2 l of ion exchanged water and stirred to obtain a suspension. Aqueous solutions respectively containing 3.5 g of chloropratinic acid, 3 g of zinc nitrate and 13 g of aluminium nitrate were successively added to the suspension, which was then stirred for one day. The solids were recovered, washed with water and dried at 150°C to give a powdered catalyst composition containing 0.5 % of platinum, 0.2 % of zinc and 0.3 % of aluminium. Example 9 100 g of hydroxyapatite was added to 1 I of ion exchanged water, and the whole was stirred and heated to 85°C to obtain a suspension. 6.5 g of tin chloride in aqueous solution and 30 g of titanium (IV) sulphate, also in aqueous solution, were successively added to the suspension. Stirring was continued at 85°C for 8 hours. The solids were then recovered, washed with water and dried at 400°C. A powdered catalyst composition containing 3.5 % of tin and 5.0 % of titanium was obtained. Example 10 200 g of calcium secondary phosphate was suspended under stirring in 2 l of ion exchanged water. To the suspension there were successively added aqueous solutions containing 19 g of barium nitrate, 15 g of iridium (II) chloride, 35 g of rhodium (III) sulphate, 45 g of zinc nitrate, 150 g of magnesium sulphate and 25 g of silver nitrate. Stirring was continued for 5 days, following which the solids were recovered, washed with water and dried at 120°C. A powdered catalyst composition containing 4 % of barium, 4.5 % iridium, 4 % of rhodium, 4% of zinc, 7 % of magnesium and 6.5 % of silver was obtained. Example 11 200 g of calcium hydroxide was added to 3 l of ion exchanged water in which there had been dissolved 9 g of silver nitrate and 12 g of zinc nitrate. The mixture was stirred to obtain a solution. Aqueous phosphoric acid was added to the solution and hydroxyapatite was produced by the usual process. After stirring for 3 days, the solids were recovered. Washing with water and drying at 200°C gave a powdered catalyst composition containing 1.7 % of silver and 0.8 % of zinc. Comparative Example 1 500 g of aluminium phosphate was suspended under stirring in 5 l of ion exchanged water. 0.4 g of silver nitrate in aqueous solution was added to the suspension, which was stirred for 2 days. The solids were then recovered, washed with water and dried at 300°C. A powdered catalyst composition containing 0.03 % of silver was obtained. Comparative Example 2 200 g of magnesium oxide was added to 2 l of ion exchanged water and stirred to form a suspension. The suspension was heated to 85°C. 6.5 g of tin chloride in aqueous solution and 30 g of titanium sulphate, also in aqueous solution, were successively added to the suspension at 85°C. Stirring at 85°C was continued for 8 hours. The solids were then recovered, washed with water and dried at 400°C to give a powdered catalyst composition containing 1.9 % of tin and 2.6 % of titanium. Comparative Example 3 500 g of calcium tertiary phosphate was suspended under stirring in 5 l of ion exchanged water. 0.4 g of silver nitrate in aqueous solution was added to the suspension, which was then stirred for 2 days. The solids were then recovered, washed with water and dried at 350°C. A powdered catalyst composition containing 0.04 % of silver was obtained. Comparative Example 4 100 g of alumina was added to 1 l of ion exchanged water and stirred to obtain a suspension. The suspension was heated to 85°C. 6.5 g of tin chloride in aqueous solution and 30 g of titanium (IV) sulphate, also in aqueous solution, were successively added to the suspension at 85°C. Stirring was continued at 85°C for 8 hours, following which the solids were recovered, washed with water and dried at 400°C. A powdered catalyst composition containing 5.0 % of titanium and 3.5 % of tin was obtained. Comparative Example 5 200 g of calcium hydroxide was dissolved in 3 l of ion exchanged water. Aqueous phosphoric acid was added to the solution and hydroxyapatite was produced by the usual process. After stirring for 3 days, the solids were recovered, washed with water and dried at 200°C. Hydroxyapatite powder was obtained. Example 12 Lower alkanols were submitted to a reaction in the presence of 1.0 g of each of the catalysts obtained in Examples 1 to 5 and Comparative Examples 1 and 2. The reaction conditions were as follows: reaction temperature 400°C nitrogen flow rate 3.0 l/hour alcohol flow rate 2.0 g/hour WHSV (supply speed of the material alcohol/g·catalyst) 2 hour -1 reaction pressure atmospheric pressure The results obtained are shown in Tables 1 and 2. The results for the catalysts of Examples 1, 3, 4 and 5 and of Comparative Examples 1 and 2 are those obtained after the alcohols were supplied for 8 hours. The results for the catalyst of Example 2 are those obtained after the alcohol was supplied for 8 hours (2-1) and for 80 hours (2-2). sample comparative example 1 comparative example 2 supplied alcohol methanol ethanol conversion rate (%) 42 41 composition (Wt%) ethers 23.2 24.2 C 1 3.2 2.6 C 2 71.9 69.7 C 3 1.7 3.5 C 4 - - C 5 - - C 5 above - - Example 13 Lower alkanols were submitted to a reaction in the presence of 1.0 g of each of the catalysts obtained in Examples 6 to 11 and Comparative Examples 3 to 5. The reaction conditions were as follows: reaction temperature 420°C nitrogen flow rate 3 l/hour alcohol flow rate 2.0 g/hour WHSV 2 hour -1 reaction pressure atmospheric pressure reactor microreactor The results obtained are shown in Tables 3 and 4. The results for the catalysts of Examples 6 and 8 to 11 and of Comparative Examples 3 to 5 are those obtained after the alcohols were supplied for 8 hours. The results obtained for the catalyst of Example 7 are those obtained after the alcohol was supplied for 8 hours (7-1) and 80 hours (7-2). A similar reaction was carried out using silver powder as catalyst and the result obtained after the alcohol was supplied for 8 hours is shown in Table 4 as Comparative Example 6.

Claims: A method for the preparation of petroleum type hydrocarbons, the method comprising contacting an alkanol, alkanediol, polyol or hydrated alcohol having from 1 to 4 carbon atoms with a catalyst at from 200 to 600°C, the supply rate per hour of the alkanol, alkanediol, polyol or hydrated alcohol being up to 15 times the weight of catalyst, wherein the catalyst comprises one or more metals and/or metal ions selected from Ti, Mn, Fe, Co, Ni, Cu, Pt, Ir, Rh, Ag, the alkali metals, the alkaline earth metals, Zn, Al and Sn supported on a carrier of zirconyl phosphate, magnesium phosphate, barium phosphate, zinc phosphate or a calcium phosphate compound, or a mixture of two or more thereof, the content of metal and/or metal ion being from 0.1 to 30% by weight with respect to the carrier. A method according to claim 1 in which the metals and/or metal ions of the catalyst are selected from Ti, Ni, Cu, Zn, Rh, Ag, Ir, Pt, Mg, Ca, Ba, Al and Sn. A method according to claim 1 or claim 2 in which the calcium phosphate compound is hydroxyapatite, calcium tertiary phosphate, calcium secondary phosphate, calcium primary phosphate, calcium pyrophosphate, calcium metaphosphate, fluorapatite, calcium quaternary phosphate or calcium octaphosphate. A method according to any preceding claim in which methanol is contacted with the catalyst. A method according to any preceding claim in which the supply rate per hour of the alkanol, alkanediol, polyol or hydrated alcohol is from 0.75 to 3.0 times the weight of catalyst.

Inventors: ATSUMI KIMINORI, INOSE AKIRA, KOYAMA HIDEO, SAKUMA SHUJI, ATSUMI, KIMINORI, INOSE, AKIRA, KOYAMA, HIDEO, SAKUMA, SHUJI, ATSUMI, KIMINORI, C/O KABUSHIKI KAISHA SANGI, Inose, Akira, c/o Kabushiki Kaisha Sangi, Koyama, Hideo, c/o Kabushiki Kaisha Sangi, SAKUMA, SHUJI, C/O KABUSHIKI KAISHA SANGI
Applicants: SANGI KK, SANGI CO., LTD.
Application year: 1993
Main classification: C10G3
IPC codes: B01J27, C10G3