FCC catalyst additive and binder

Abstract

Provided is a process for manufacturing a Fluid Catalytic Cracking catalyst additive composition with a novel binder. The steps involve mixing an alumina source with water to make a slurry; adding to the alumina slurry an amount of P2O5 source; the slurry is then stirred and reacted under controlled temperature and time conditions to form an aluminum phosphate binder; adding to the aluminum phosphate binder a zeolite, an amount of silica binder and an amount of clay; and spray-drying the slurry to form catalyst additive particles. The catalyst additive composition comprises a about 35 wt % to about 65 wt % zeolite; about 0 wt % to about 10 wt % silica; about 15 wt % to about 50 wt % clay and an aluminum phosphate binder comprising about 2.5 wt % to 5 wt % amorphous or pseudo-boehmite alumina and about 7 wt % to 15 wt % phosphoric acid.

Claims

1. A process for the preparation of a catalyst additive comprising the following steps: a. mixing an alumina source with water to make a slurry; b. adding to the slurry of step (a) an amount of P.sub.2O.sub.5 source; c. the slurry of step (b) is then stirred and reacted at a temperature above 5 C. but not higher than 60 C. and under time conditions to form an aluminum phosphate binder; d. adding to the aluminum phosphate binder a zeolite, an amount of silica binder and an amount of clay; and e. spray-drying the slurry of step (d) to form catalyst additive particles.

2. The process of claim 1 further comprising the step of calcining the catalyst additive particles after step (e) at a temperature of between about 350 C. and about 700 C.

3. The process of claim 1 wherein the alumina source is amorphous or pseudoboehmite alumina added in an amount of less than about 5 wt %.

4. The process of claim 3 wherein the amorphous or pseudoboehmite alumina is added in amount of greater than about 2.5 wt % and less than about 5 wt %.

5. The process of claim 1 wherein the solids content of the slurry of step (a) to be between about 5 wt % and about 30 wt % Al.sub.2O.sub.3.

6. The process of claim 1 wherein the solids content of the slurry of step (a) to be between about 9 wt % and about 30 wt % Al.sub.2O.sub.3.

7. The process of claim 1 wherein the source of the amount of P.sub.2O.sub.5 is H.sub.3PO.sub.4 and the P.sub.2O.sub.5 is added in an amount between about 7 wt % and 15 wt %, by dry weight basis.

8. The process of claim 1 wherein the source of the amount of P.sub.2O.sub.5 is H.sub.3PO.sub.4 and the P.sub.2O.sub.5 is added in an amount between about 8 wt % and 12 wt %, by dry weight basis.

9. The process of claim 1 wherein the P/Al molar ratio at step (b) is between 1 and 3.

10. The process of claim 1 wherein the P/Al molar ratio at step (b) is between 1.5 and 2.5.

11. The process of claim 1 wherein the silica binder is added in the range of greater than about 0 wt % to about 10 wt %.

12. The process of claim 1 wherein the silica binder is added in the range of about 3 wt % to about 8 wt %.

Description

EXAMPLES

(1) The invention is illustrated in the following non-limiting examples, which are provided for the purpose of representation, and are not to be construed as limiting the scope of the invention.

(2) Prior to any lab testing the catalyst must be deactivated to simulate catalyst in a refinery unit, this is typically done with steam. These samples were deactivated with 100% steam at 788 C. or 800 C. for 20 hours. It should be noted that while this example is done as a Fluidized Bed Simulation, the propylene yield at a given conversion is essentially the same as that which would be given in commercial practice because lab deactivated catalyst mimics catalyst deactivated in a FCC unit. The Fluid microactivity test, or Fluidized-bed Simulation Test (FST) is a test known and generally accepted in the art for ascertaining the FCC cracking activity of a catalyst. The test is conducted with a series of catalyst-to-feed ratios (CTO) which are obtained by varying the mass of catalyst present in the reactor while using the same feed rate for all runs. The testing apparatus simulates the cracking of a known amount of a hydrocarbon feedstock of known amount and compositional characteristics. This small scale testing unit is a once through unit and operated approximately as in ASTM 5154-10. The reactor is in a hot furnace and the catalyst is added directly to the reactor followed by the feed injection, as outlined below. Then, 4.5 to 9 grams of catalyst were loaded into the FST unit. The reaction temperature was fixed at 537 C. 1.5 grams of a hydrocarbon feed are injected at a rate of 1.5 grams per minute. The gas and liquid products were collected and their component proportions were analyzed by GC. The weight percent conversion is the weight percent of the feed which is converted into coke, gas and gasoline:
100[(weight of feed)(weight of light cycle oil produced)(weight of bottoms/residue formed, excluding coke on catalyst]/[weight of feed]
For testing additives one blends it with a FCC catalyst prior to performance testing at concentrations to simulate commercial use. For the following examples, additives were blended at 5% blends.

(3) The weight of the coke on the catalyst is measured by removing the catalyst from the reactor after the reaction and subjecting it to analysis by a LECO carbon analyzer.

(4) The examples below utilize a typical VGO crude oil. Other feeds can be used and the feed properties do impact the absolute yields of LPG and in particular propylene.

Example 1

(5) Five additive samples were made using the methodology described herein. A sixth base case made by way of prior methods was also used. The five additives were then performance tested to determine propylene yields (reported values are at CTO=4) after blending it in to an Ecat at 5% level.

(6) TABLE-US-00001 Base Case Example A Example B Example C Example D Example E ZSM5 40 40 50 50 50 50 pseudo-boeh 3.8 3.8 3.8 3.8 3.8 P.sub.2O.sub.5 9.5 10.5 11 11.5 12 ABD 0.70 0.71 0.72 0.72 0.73 0.73 Attrition 0.4 0.25 0.49 0.39 0.32 0.3 Propylene, 8.96 9.80 9.88 8.75 8.23 7.52 wt % CTO = 4

Example 2

(7) Another aspect of the additive was tested by varying the solids of the alumina prior to the addition of the H.sub.3PO.sub.4. Four samples of the additive were made in accordance with the invention described herein. The same weight percent of ingredients were used while the alumina solid percentage was varied. The resulting tests showed that to maintain preferred physical properties of the additive, the alumina slurry should preferably be maintained above 9 wt % solids during the synthesis of the AlP material as shown in the table below.

(8) TABLE-US-00002 Alumina Alumina Alumina Alumina Solid: Solid: Solid: Solid: 8% 9% 10% 12% ABD 0.69 0.69 0.69 0.7 Attrition 1.6 0.65 0.6 0.65

Example 3

(9) Another aspect of the invention is that the reaction mixture of aluminum and phosphate is preferably maintained below a set temperature. When done so, the process yields an additive after spray drying that will have acceptable physical properties. Two examples were made in accordance with the invention described herein. The same weight percent of ingredients were used while the temperature of the aluminum and phosphorous mixture was varied. The samples were in both examples allowed to react for 5 minutes prior to mixing with all other ingredients. The table below shows that when the AlP mixture reached a temperature of 64 C. the attrition increased from the sample which had a temperature of 55 C. for the AlP mixture.

(10) TABLE-US-00003 Example 3-1 Example 3-2 Temp Al-P ( C.) 55.0 64.0 ABD 0.7 0.7 Attrition 0.4 1.8

Example 4

(11) Another aspect of the invention is that order of addition affects the properties of the final catalyst. Four samples of the additive were made in accordance with the invention described herein. The same weight percent of ingredients were used while the order of addition was varied for each sample. The samples were allowed to react for 5 minutes prior to mixing with all other ingredients. The first sample was prepared by reacting alumina in the presence of phosphoric acid. The second sample was prepared by reacting the alumina with the phosphoric acid in the presence of zeolite. The third sample was prepared by reacting alumina with phosphoric acid in the presence of clay. The fourth sample was prepared by reacting alumina with phosphoric acid in the presence of clay and silica. The physical properties are disclosed in the below table. The results show poor calcined attrition values for each sample wherein the alumina is reacted with the phosphoric acid in the presence of another ingredient, not including water or other aqueous solution.

(12) TABLE-US-00004 H.sub.3PO.sub.4 + H.sub.3PO.sub.4 + H.sub.3PO.sub.4 + H.sub.3PO.sub.4 + Pseudo- Pseudo-boeh + Pseudo-boeh + Pseudo-boeh + boeh Zeolite clay clay + Si-sol ABD 0.73 0.70 0.73 0.73 Attrition 0.4 10.1 1.0 3.4

(13) As used herein, the term about modifying the quantity of an ingredient in the compositions of the invention or employed in the methods of the invention refers to variation in the numerical quantity that can occur, for example, through typical measuring and liquid handling procedures used for making concentrates or use solutions in the real world; through inadvertent error in these procedures; through differences in the manufacture, source, or purity of the ingredients employed to make the compositions or carry out the methods; and the like. The term about also encompasses amounts that differ due to different equilibrium conditions for a composition resulting from a particular initial mixture. Whether or not modified by the term about, the claims include equivalents to the quantities.

(14) Except as may be expressly otherwise indicated, the article a or an if and as used herein is not intended to limit, and should not be construed as limiting, the description or a claim to a single element to which the article refers. Rather, the article a or an if and as used herein is intended to cover one or more such elements, unless the text expressly indicates otherwise. This invention is susceptible to considerable variation in its practice. Therefore the foregoing description is not intended to limit, and should not be construed as limiting, the invention to the particular exemplifications presented hereinabove.