阅读说明：本技术 凝点低的柴油馏分异构降凝催化剂 (Diesel oil fraction isomeric pour point depressing catalyst with low freezing point ) 是由 陈彦霖 凌宇鑫 于 2021-09-03 设计创作，主要内容包括：本发明提供凝点低的柴油馏分异构降凝催化剂,涉及异构降凝催化剂制备领域。该凝点低的柴油馏分异构降凝催化剂,包括以下步骤：S1.溶液制备,将铝源、碱金属源、结构导向剂按照1：1：1比列溶解于水中制成金属盐溶液；S2.搅拌,在金属盐溶液中加入晶种和硅源,充分搅拌,形成稳定凝胶；S3.混合,将贵金属以共晶化的过程引入,制成水溶液,然后将所述S2中得到的稳定凝胶缓慢加入贵金属水溶液,边加入边搅拌使其混合均匀,得到混合物。本发明提供凝点低的柴油馏分异构降凝催化剂,该凝点低的柴油馏分异构降凝催化剂制备效率和活性更高,凝点和浊点更低,可以在柴油馏分过程中起到更好的催化作用。(The invention provides a diesel oil fraction isomerization pour point depressing catalyst with low pour point, and relates to the field of preparation of isomerization pour point depressing catalysts. The diesel oil fraction isomerization pour point depression catalyst with low freezing point comprises the following steps: s1, preparing a solution, namely preparing an aluminum source, an alkali metal source and a structure directing agent according to the weight ratio of 1: 1: dissolving 1 proportion of the mixture in water to prepare a metal salt solution; s2, stirring, namely adding seed crystals and a silicon source into a metal salt solution, and fully stirring to form stable gel; and S3, mixing, namely introducing the noble metal in a co-crystallizing process to prepare an aqueous solution, slowly adding the stable gel obtained in the step S2 into the aqueous solution of the noble metal, and stirring while adding to uniformly mix the stable gel and the aqueous solution of the noble metal to obtain a mixture. The invention provides a diesel fraction isomerization pour point depression catalyst with low freezing point, which has higher preparation efficiency and activity, lower freezing point and cloud point and can play a better catalysis role in the diesel fraction process.)

1. The diesel oil fraction isomerization pour point depressing catalyst with low pour point is characterized in that: the method comprises the following steps:

s1, preparing a solution, namely preparing an aluminum source, an alkali metal source and a structure directing agent according to the weight ratio of 1: 1: dissolving 1 proportion of the mixture in water to prepare a metal salt solution;

s2, stirring, namely adding seed crystals and a silicon source into a metal salt solution, and fully stirring to form stable gel;

s3, mixing, namely introducing a noble metal in a co-crystallization process to prepare an aqueous solution, slowly adding the stable gel obtained in the step S2 into the aqueous solution of the noble metal, and stirring while adding to uniformly mix the stable gel and the aqueous solution of the noble metal to obtain a mixture;

s4, crystallizing, namely performing precipitation crystallization on the mixture obtained in the S3 in a crystallization reaction kettle;

s5, preparing, namely washing, drying, roasting, grinding and molding the crystallized product, and then activating to prepare the heterogeneous pour point depressing catalyst.

2. The low pour point diesel distillate isomerization pour point depressant catalyst of claim 1, wherein: the aluminum source in the step S1 is one or more of aluminum sulfate, sodium metaaluminate and aluminum isopropoxide.

3. The low pour point diesel distillate isomerization pour point depressant catalyst of claim 1, wherein: the alkali metal source of the S1 step is sodium hydroxide or potassium hydroxide.

4. The low pour point diesel distillate isomerization pour point depressant catalyst of claim 1, wherein: the structure directing agent of the step S1 is one or more of cetyl trimethyl ammonium bromide, dodecyl trimethyl ammonium bromide and sodium dodecyl sulfonate.

5. The low pour point diesel distillate isomerization pour point depressant catalyst of claim 1, wherein: the silicon source in the step S2 is one or more of water glass, silica sol, fumed silica, and tetraethoxysilane.

6. The low pour point diesel distillate isomerization pour point depressant catalyst of claim 1, wherein: the pH value of the crystallization in the step S4 is 6.3-9.8.

7. The low pour point diesel distillate isomerization pour point depressant catalyst of claim 1, wherein: and (3) preparing and molding by using an acid solution before the drying step in the step S4.

8. The low pour point diesel distillate isomerization pour point depressant catalyst of claim 1, wherein: the crystallization temperature in the S4 step is 100-200 ℃, and the crystallization time is 12-72 h.

Technical Field

The invention relates to the field of preparation of heterogeneous pour point depressing catalysts, in particular to a diesel oil fraction heterogeneous pour point depressing catalyst with a low pour point.

Background

The crude oil is firstly pretreated before petroleum refining, namely, desalting and water are firstly carried out, then normal pressure distillation is carried out, namely, the crude oil is separated into gasoline fraction with the boiling point range of 35-205 ℃, kerosene fraction with the boiling point range of 140 ℃ plus 280 ℃, diesel fraction with the boiling point range of 200 plus 350 ℃, the lower part of the distillation tower with the lower temperature is reached from the upper part with the lower boiling point, and the higher heavy fraction is difficult to evaporate and can only be evaporated at the lower part with the higher temperature by utilizing the difference of the boiling points of hydrocarbons in the crude oil. Namely gasoline fraction, kerosene fraction and diesel oil fraction from light to heavy; the gasoline, kerosene and diesel oil are sequentially produced through catalytic cracking and hydrocracking, wherein a catalyst is required during catalysis.

A prior art patent (application No. 201310291173.9) discloses a hydroisomerization/cracking catalyst and a process for its preparation. The catalyst consists of an acidic heterogeneous cracking carrier and a metal active component loaded on the acidic heterogeneous cracking carrier; the acidic heterogeneous cracking carrier consists of a ZSM-22 molecular sieve and an amorphous oxide; the mass ratio of the acidic heterogeneous cracking carrier to the metal active component is 70-99.9: 0.1 to 30, wherein the mass of the metal active component is calculated by the mass of the oxide and/or the element thereof; the method has the advantages that the high-melting-point long-chain n-alkane can be cracked into light diesel oil, a small amount of gas and naphtha are generated, and the condensation point of the product is effectively reduced.

Another patent (application number: 201510408501.8) discloses a catalyst for isomerizing pour point depression of middle distillate oil synthesized by F-T and a special composite molecular sieve with a core-shell structure. The composite molecular sieve takes a microporous ZSM-22 molecular sieve as a core and a mesoporous MCM-41 molecular sieve as a shell, and the relative proportion of the microporous ZSM-22 molecular sieve and the mesoporous MCM-41 molecular sieve is adjustable. The preparation method comprises the following steps: firstly, preparing a ZSM-22 molecular sieve, adding alkali and an organic template agent into a mixed system containing the ZSM-22 molecular sieve for pre-crystallization, adjusting the pH value to 6.5-13.5, and performing crystallization treatment to obtain the ZSM-22 molecular sieve; the catalyst prepared by taking the core-shell structure ZSM-22/MCM-41 composite molecular sieve as the carrier is applied to the hydroisomerization reaction of middle distillate oil in F-T synthesis, and has the advantages of higher isomerization selectivity, and particularly obviously improved selectivity of multi-branched alkane.

Another patent (application No. 201611098923.0) discloses a catalyst for hydroisomerization and its preparation method and application. The catalyst consists of one or two metals of Pt, Pd and Ir in the VIII group noble metal with the content of 0.05-5 wt%, a ZSM-22 molecular sieve containing organic matters or carbon deposition and amorphous oxide; its advantage is that compared with catalyst prepared by existing technique, the catalyst prepared by the invention has higher selectivity and yield of isomeric alkane in alkane hydroisomerization reaction.

The three patents all provide respective solutions for the preparation of the isomerization catalyst, and the applicant finds that the specific surface area and the pore volume of the catalyst prepared by any method are lower, and the catalytic effect is poor when the diesel fraction is caused by insufficient activity in the actual operation, so that the diesel fraction isomerization pour point depressing catalyst with low freezing point is provided.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a diesel fraction isomerization pour point depressing catalyst with low pour point, and solves the problems of low specific surface area, low pore volume and insufficient activity of the catalyst in the prior art.

(II) technical scheme

In order to achieve the purpose, the invention is realized by the following technical scheme: a diesel fraction isomerization pour point depressing catalyst with low pour point comprises the following steps:

s1, preparing a solution, namely preparing an aluminum source, an alkali metal source and a structure directing agent according to the weight ratio of 1: 1: dissolving 1 proportion of the mixture in water to prepare a metal salt solution;

s2, stirring, namely adding seed crystals and a silicon source into a metal salt solution, and fully stirring to form stable gel;

s3, mixing, namely introducing a noble metal in a co-crystallization process to prepare an aqueous solution, slowly adding the stable gel obtained in the step S2 into the aqueous solution of the noble metal, and stirring while adding to uniformly mix the stable gel and the aqueous solution of the noble metal to obtain a mixture;

s4, crystallizing, namely performing precipitation crystallization on the mixture obtained in the S3 in a crystallization reaction kettle;

s5, preparing, namely washing, drying, roasting, grinding and molding the crystallized product, and then activating to prepare the heterogeneous pour point depressing catalyst.

Preferably, the aluminum source in the step S1 is one or more of aluminum sulfate, sodium metaaluminate and aluminum isopropoxide.

Preferably, the alkali metal source of step S1 is sodium hydroxide or potassium hydroxide.

Preferably, the structure directing agent of step S1 is one or more of cetyltrimethylammonium bromide, dodecyltrimethylammonium bromide, and sodium dodecylsulfonate.

Preferably, the silicon source in step S2 is one or more of water glass, silica sol, fumed silica, and tetraethoxysilane.

Preferably, the PH value of the crystallization in the S4 step is 6.3 to 9.8.

Preferably, the preparation and molding are performed with an acid solution before the drying step in the step S4.

Preferably, the crystallization temperature in the step of S4 is 150 ℃, and the crystallization time is 24 h.

(III) advantageous effects

The invention provides a diesel fraction isomerization pour point depressing catalyst with low pour point. The method has the following beneficial effects:

1. the invention provides a diesel fraction isomerization pour point depressing catalyst with low condensation point, which is synthesized by a molecular sieve prepared by an aluminum source and noble metals, so that the noble metals can be uniformly distributed in the molecular sieve, the purpose of improving the surface area and the pore volume of the catalyst is achieved, and the preparation raw materials have rich sources and smaller preparation difficulty.

2. The invention provides a diesel oil fraction isomerization pour point depressing catalyst with low freezing point, which does not need a precipitator, and directly leads the crystallization object to be formed through a plurality of procedures of washing, drying, roasting, grinding, and the like, and then to be activated, thus leading the activity and the selectivity of the obtained catalyst to be higher.

3. The invention provides a diesel fraction isomerization pour point depression catalyst with low freezing point, the method prepares a primary product through crystallization in the preparation process, the preparation is quick and effective, and compared with the traditional hydrothermal synthesis method, the method has lower freezing point and cloud point.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The first embodiment is as follows:

the embodiment of the invention provides a diesel fraction isomerization pour point depressing catalyst with low freezing point, which comprises the following steps:

s1, preparing a solution, namely preparing an aluminum source, an alkali metal source and a structure directing agent according to the weight ratio of 1: 1: dissolving 1 proportion of the mixture in water to prepare a metal salt solution;

s2, stirring, namely adding seed crystals and a silicon source into a metal salt solution, and fully stirring to form stable gel;

s3, mixing, namely introducing a noble metal in a co-crystallization process to prepare an aqueous solution, slowly adding the stable gel obtained in the step S2 into the aqueous solution of the noble metal, and stirring while adding to uniformly mix the stable gel and the aqueous solution of the noble metal to obtain a mixture;

s4, crystallizing, namely performing precipitation crystallization on the mixture obtained in the S3 in a crystallization reaction kettle;

s5, preparing, namely washing, drying, roasting, grinding and molding the crystallized product, and then activating to prepare the heterogeneous pour point depressing catalyst.

Wherein the PH value is firstly adjusted to 6.3 during crystallization, the crystallization temperature is 100 ℃, and the crystallization time is 12 hours before crystallization treatment.

Example two:

the embodiment of the invention provides a diesel fraction isomerization pour point depressing catalyst with low freezing point, which is characterized in that: the method comprises the following steps:

s1, preparing a solution, namely preparing an aluminum source, an alkali metal source and a structure directing agent according to the weight ratio of 1: 1: dissolving 1 proportion of the mixture in water to prepare a metal salt solution;

s2, stirring, namely adding seed crystals and a silicon source into a metal salt solution, and fully stirring to form stable gel;

s3, mixing, namely introducing a noble metal in a co-crystallization process to prepare an aqueous solution, slowly adding the stable gel obtained in the step S2 into the aqueous solution of the noble metal, and stirring while adding to uniformly mix the stable gel and the aqueous solution of the noble metal to obtain a mixture;

s4, crystallizing, namely performing precipitation crystallization on the mixture obtained in the S3 in a crystallization reaction kettle;

s5, preparing, namely washing, drying, roasting, grinding and molding the crystallized product, and then activating to prepare the heterogeneous pour point depressing catalyst.

Wherein the PH value is firstly adjusted to 6.3 during crystallization, the crystallization temperature is 200 ℃, and the crystallization time is 12 hours before crystallization treatment.

Example three:

the embodiment of the invention provides a diesel fraction isomerization pour point depressing catalyst with low freezing point, which is characterized in that: the method comprises the following steps:

s1, preparing a solution, namely preparing an aluminum source, an alkali metal source and a structure directing agent according to the weight ratio of 1: 1: dissolving 1 proportion of the mixture in water to prepare a metal salt solution;

s2, stirring, namely adding seed crystals and a silicon source into a metal salt solution, and fully stirring to form stable gel;

s3, mixing, namely introducing a noble metal in a co-crystallization process to prepare an aqueous solution, slowly adding the stable gel obtained in the step S2 into the aqueous solution of the noble metal, and stirring while adding to uniformly mix the stable gel and the aqueous solution of the noble metal to obtain a mixture;

s4, crystallizing, namely performing precipitation crystallization on the mixture obtained in the S3 in a crystallization reaction kettle;

s5, preparing, namely washing, drying, roasting, grinding and molding the crystallized product, and then activating to prepare the heterogeneous pour point depressing catalyst.

Wherein the PH value is firstly adjusted to 6.3 during crystallization, the crystallization temperature is 100 ℃, and the crystallization time is 72 hours before crystallization treatment.

Example four:

the embodiment of the invention provides a diesel fraction isomerization pour point depressing catalyst with low freezing point, which is characterized in that: the method comprises the following steps:

s1, preparing a solution, namely preparing an aluminum source, an alkali metal source and a structure directing agent according to the weight ratio of 1: 1: dissolving 1 proportion of the mixture in water to prepare a metal salt solution;

s2, stirring, namely adding seed crystals and a silicon source into a metal salt solution, and fully stirring to form stable gel;

s3, mixing, namely introducing a noble metal in a co-crystallization process to prepare an aqueous solution, slowly adding the stable gel obtained in the step S2 into the aqueous solution of the noble metal, and stirring while adding to uniformly mix the stable gel and the aqueous solution of the noble metal to obtain a mixture;

s4, crystallizing, namely performing precipitation crystallization on the mixture obtained in the S3 in a crystallization reaction kettle;

s5, preparing, namely washing, drying, roasting, grinding and molding the crystallized product, and then activating to prepare the heterogeneous pour point depressing catalyst.

Wherein the PH value is firstly adjusted to 9.8 during crystallization, the crystallization temperature is 100 ℃, and the crystallization time is 12 hours before crystallization treatment.

Example five:

the embodiment of the invention provides a diesel fraction isomerization pour point depressing catalyst with low freezing point, which is characterized in that: the method comprises the following steps:

s1, preparing a solution, namely preparing an aluminum source, an alkali metal source and a structure directing agent according to the weight ratio of 1: 1: dissolving 1 proportion of the mixture in water to prepare a metal salt solution;

s2, stirring, namely adding seed crystals and a silicon source into a metal salt solution, and fully stirring to form stable gel;

s3, mixing, namely introducing a noble metal in a co-crystallization process to prepare an aqueous solution, slowly adding the stable gel obtained in the step S2 into the aqueous solution of the noble metal, and stirring while adding to uniformly mix the stable gel and the aqueous solution of the noble metal to obtain a mixture;

s4, crystallizing, namely performing precipitation crystallization on the mixture obtained in the S3 in a crystallization reaction kettle;

s5, preparing, namely washing, drying, roasting, grinding and molding the crystallized product, and then activating to prepare the heterogeneous pour point depressing catalyst.

Wherein the PH value is firstly adjusted to 9.8 during crystallization, the crystallization temperature is 200 ℃, and the crystallization time is 72 hours before crystallization treatment.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.