石油碳五馏份加氢制备戊烷的方法

Technical Field

The invention relates to non-saturated hydrocarbons through hydrogenation process for manufacturing alkanes, in particular to contain by using hydrogenation of unsaturated hydrocarbons method of preparing pentane.

Background Art

Petroleum cracking of ethylene in the process of a considerable number of refined by-product, to the refined to improve ethylene is an effective means of production economic benefit. At present, the comprehensive utilization of the refined carbon five separation is mainly to, get isoprene, piperyene-olefin such as a relatively high value and inhibiting application. In the many-containing preparations is very close to the boiling point of the compound, with the general separation method to be separated from the filter is not reversed in, most of the people adopt the separation method is methyl tertiary amyl ether crack solution, in other words carbon five fraction of the methanol reaction to produce methyl tert-amyl ether, and then through the high temperature cracking, the cracked product contains isopentenes, methanol and a small amount of impurity, after the water washing removal of methanol, and the rectification can make the high purity isopentenes. Extracting the double-olefin and method adopting the above-mentioned methyl tertiary amyl ether crack separated isopentenes raffinate carbon five material can be used as a fuel oil to use, but it is clear that the use of more economic benefit is the high re-deep processing, for example, can be prepared by hydrogenation of pentane. Pentane is an important basic chemical raw materials, can be used for producing pentanol, Pentanal, and the like, can be used as a high molecular material and a foaming agent and the extractant, can also be used as a green refrigerant substitute freons, at the same time, it is also a good organic solvent.

Chinese Patent ZL95111774.2 raised to a similar semicircular preparing pentane through catalyst hydrogenation method, wherein the activity of the catalyst components are Pd, precious metal such as Pt, or cu, Co, Ni, or Mo non-noble metal element such as Fe. The method uses without methyl tertiary amyl ether crack solution extraction isopentene pentane as materials to prepare refined is an ideal, however, because extraction hydrolysis of the methyl tertiary amyl ether crack in the refined filter comprising water, methanol, methyl tert-amyl ether, dimethyl ether and other trace impurities, these oxygen-containing group impurity although content is very low, but the Pd noble metal catalyst poisoning caused by, in particular, in a short time, even in the catalyst deactivation. The non-noble metal catalyst although the problem of catalyst poisoning does not exist, the yield of the pentane, however, is relatively low, and more harsh reaction conditions.

Content of the invention

This invention has offered a kind of by using hydrogenation method for preparing pentane, it is the technical problem to be solved is the double extraction can be the methyl tertiary amyl ether crack olefin and separating the decomposition the raffinate obtained after isopentene carbon five as a raw material by a hydrogenation reaction to the preparation of high-purity pentanes, the requirements of the catalyst poisoning is not easy to be oxygen-containing group, but also have relatively high yield of pentane, so as to overcome the defects of the prior art.

The following is the present invention solve the above technical problem the technical proposal:

A preparing pentane by using hydrogenation method, this method, in order to extract the double-olefin and hydrolysis of the methyl tertiary amyl ether crack Prenyl obtained after separating the raffinate carbon as raw material, the raw material carbon five hydrogenation in the presence of a catalyst to obtain high-purity pentanes, the reaction temperature is 40-300 the [...] , the reaction pressure is 0-5MPa, carbon five raw materials for the liquid hourly space velocity of 0.3-10hr^-1, natron the molar feed ratio is 0.7-8.0, catalyst to Al₂ O₃ as the carrier, load of the active group containing Pd and component parts A, from A Mo, Zn cu or in a mixture of more than two or, in the catalyst of the Pd content is 0.1-1.0 wt %, the content of the component A 0.5-1.8 wt %.

The above-mentioned catalyst active components is preferably A Mo, the content of the active component Pd is preferably 0.2-0.4 wt %, the content of the active component A is preferably 0.8-1.0 wt %, although the content of the Pd will be raised to increase the reaction activity, but when more than 1.0 wt % economical efficiency will be reduced; the reaction temperature is preferably the 100-150 [...] ; the reaction pressure is preferably 0.5-2.0 MPa; carbon five raw materials for the liquid hourly space velocity of 1.0-5.0hr^-1; the molar feed ratio of hydrogen with natron preferably 1.0-5.0.

The essence of invention is suitable for a catalyst of non-noble metal to Pd/Al₂ O₃ modified, in ensuring Pd/Al₂ O₃ the activity of the catalyst is high, on the premise of the craft mild condition, to increase the depth of the hydrogenation reaction. The inventor has also been found by numerous experiments, the modified can be avoided of a noble metal catalyst poisoning impurities are oxygen-containing group.

Catalyst is well known in the technical field, the dipping process, the following preparation process is only inventor recommended:

First of all, the average particle size is 3 mm the left and right, specific surface area is 160-220m²/g of the spherical alumina carrier in the 120 [...] -200 the drying in the temperature range of [...] , then according to the-equivoluminal impregnated by a plurality of times, the different active components loaded onto the carrier, finally after drying and calcining, the active components on the carrier after the suitable distribution state of the catalyst is finished. Each active component of the raw material is generally made of water-soluble salt.

The hydrogenation process of this invention the reaction temperature the 40-300 [...] , the reaction pressure is 0-5 MPa, carbon five raw materials for the liquid hourly space velocity of 0.3-10hr^-1, natron the molar feed ratio is 0.7-8.0 range of the process conditions are possible. However, wherein the reaction temperature is preferably 100 the the [...] -150 [...] , too low temperature conversion of olefin is reduced, although higher reaction temperature can improve the reaction activity, further improve the olefin conversion, but the temperature is higher than 150 the isomerization side reaction generated after [...] increase the probability, although conversion of olefin is very high, but they yield decline in pentane. The best reaction pressure in the range of 0.5-2.0 MPa, pressure is lower than 0.5 MPa, , easily lead to carbon five-component vaporization, heat transfer rate to be reduced, the excessive temperature rise of the catalyst bed layers, the same will increase the probability of occurrence of side reactions. While the pressure more than 2.0 MPa rear, olefin conversion and pentane and increase the yield of the trend of increased pressure will slow down, the high reaction pressure in the economical efficiency of the device. Better range is the liquid hourly space velocity of 1.0-5.0hr^-1, too low to improve the liquid hourly space velocity of the olefin conversion is advantageous, however, device throughput is too low, the liquid space velocity higher than 5hr^-1 time, the decline in conversion of olefin is relatively obvious. The mol ratio hydrogen and carbon five distill share the optimum range is 1.0-5.0, hydrogen and carbon five distill share mole of ratio less than 1.0 time, conversion of olefin is too low, the higher than carbon five distill share mole 5.0 time, the trend of the conversion rate of slowing down.

Compared with the prior art, the advantage of this invention lies in the double-olefin and the extraction by the methyl tertiary amyl ether crack solution separating the raffinate obtained after isopentene carbon five as a raw material by a hydrogenation reaction to the preparation of high-purity pentanes, olefin conversion, pentane yield is up to 99% or more. Furthermore, hydrogenation reaction conditions are relatively mild process.