CN104607255A - Low-L-acid and high-B-acid catalytic cracking catalyst and preparation method thereof - Google Patents

Abstract

The invention relates to a preparation method for a catalytic cracking catalyst for petrifaction, and particularly relates to a low-L-acid and high-B-acid catalytic cracking catalyst and a preparation method thereof. The preparation method comprises the following steps: adding a catalytic cracking catalyst into deionized water, adding boric acid solution at the temperature of 20-90 DEG C, adding inorganic acid, carrying out suction filtration and washing on the product subjected to reaction, and drying and roasting the obtained filter cake to obtain the low-L-acid and high-B-acid catalytic cracking catalyst. According to the preparation method for the low-L-acid and high-B-acid catalytic cracking catalyst provided by the invention, a boron element is introduced into the catalytic cracking catalyst, so that the surface L-acid content of the catalytic cracking catalyst is reduced, and the B-acid content thereof is increased; the low-L-acid and high-B-acid catalytic cracking catalyst is capable of increasing a raw material conversion rate, effectively increasing the yields of catalytic cracking gasoline and diesel oil, and reducing the yield of light hydrocarbons when being used for catalytic cracking micro-reaction.

Description

The acid catalyzed cracking Catalysts and its preparation method of the low L high B of acid

Technical field

The present invention relates to a kind of catalytic cracking catalyst preparation method of petrochemical industry, be specially the acid catalyzed cracking Catalysts and its preparation method of the low L high B of acid.

Technical background

Catalytic cracking is mink cell focus secondary operations, produce one of important means of the clear gusoline such as gasoline, diesel oil, as the catalytic cracking catalyst of leading petroleum hydrocarbon Journal of Molecular Catalysis reaction primarily of active component and molecular sieve and matrix composition, sometimes also will by the effect of binding agent.Commercial Application requires that catalytic cracking catalyst has good physics, chemical property, as: specific surface is large, mechanical strength is high, heat endurance is strong, surface has acidity etc.Catalytic cracking catalyst has simultaneously acid (B acid) and Lewis acid (L acid).Wherein, active component Y zeolite has B acid and L acid simultaneously, and the alumina surface as main binding agent and matrix only has L acidity usually, and this two classes acidic site can play the effect of cracking to hydrocarbon molecules.Research shows, L acid has very strong adsorption capacity to unsaturated compound, polymerization and deep dehydrogenation reaction easily occurs, produces coke and dry gas.And hydro carbons mainly carries out cracking by carbenium ion mechanism on B acid position, the coke selectivity of catalyst effectively can be reduced.So regulate the acidity on catalytic cracking catalyst surface, catalyst surface is had while the sour and more B acid of less L can improve catalytic cracking product yield and reduces coke.

CN 104084233A discloses the method with boron oxide modified micro porous molecular sieve ZSM-5 and MCM-22, be that boron oxide is carried on micro porous molecular sieve outer surface by impregnation-calcination method by boron oxide presoma with ammonium pentaborate, reduce molecular sieve surface acid, the catalyst Pyrogentisinic Acid contraposition alkylation synthesis p-methyl phenol that the method obtains and paraethyl phenol process have good shape selective catalysis performance.But the method does not make embodiments and test to the acidity change of molecular sieve.

CN 103191776A discloses and directly prepares boron aluminum molecular screen B-ZSM-5 with boric acid, and infusion process and ion-exchange and carry out the method that post processing obtains boracic ZSM-5 to ZSM-5.The effect of the molecular sieve that the method obtains in MTP reaction is better.But the method does not provide modified acid characterization and the test data of molecular sieve.

CN 102728335A discloses the method with boron modification aluminium oxide, first with low-carbon alcohol solution, alumina precursor is soaked, add the BAS formed by polyalcohol and boric acid again, due to the volatilization of low-carbon alcohols and lower surface tension thereof can be boron evenly the surface being dispersed in aluminium oxide, prevent B solution from directly joining gathering aluminium oxide causing local boron.The method effectively improves specific surface and the pore volume of carrier.

The method carrying out modified aluminas with different boron-containing compounds is disclosed in the patents such as CN 1052501A, CN 1082387C, CN 1609178A.The body that boron element is all successfully incorporated into aluminium oxide by these methods mutually in, but all concrete sign and test are not made for the change of the acidity of aluminium oxide.

CN 1768945A discloses a kind of preparation method of alumina support of siliceous and titanium, and silicon adds in the plastic process of aluminium oxide, and the surface area of aluminium oxide, aperture and pore volume are improved; Titanium after plastic, aging before add, further improve the surface acidity of aluminium oxide, the total acid content of alumina surface and B acid content significantly improved.CN 1110304A discloses a kind of method of silicon and P Modification aluminium oxide, and silicon, phosphorus adopt substep plastic method to add respectively, make silicon and phosphorus more even in the dispersion of alumina surface.

CN 1853774A discloses a kind of method of Si modification aluminium oxide, add in the aqueous solution of aluminium salt alkalescence aqueous silicate solution, regulate pH formed gel, then aging, filter, washing.Record alumina surface that Si modification crosses only containing L acid with pyridine infra-red sepectrometry, there is no B acid.

Summary of the invention

For above-mentioned technical problem, the invention provides a kind of Surface L ewis acid (L acid) low, be rich in surface simultaneously the catalytic cracking catalyst of acid (B acid), with and preparation method thereof, concrete technical scheme is:

The preparation method of the acid catalyzed cracking catalyst of the low L high B of acid, comprises the following steps:

(1) catalytic cracking catalyst is added in deionized water fully stir, under the bath temperature of 20-90 DEG C, add the BAS of 0.05-2.0mol/L, wherein H ₃bO ₃be 2% ~ 20% with the mass ratio of catalytic cracking catalyst;

(2) add inorganic acid in the mixed liquor obtained to step (1), inorganic acid is one or more mixtures of hydrochloric acid, nitric acid, sulfuric acid, regulates this mixed system pH value to be 2.0-6.0; Then successive reaction 0.5-24h in 20-90 DEG C of water-bath;

(3) gained mixture is filtered, washed, the filter cake of gained is dry at 50-200 DEG C, the roasting 2-24h at 500 DEG C-700 DEG C, obtains the acid catalyzed cracking catalyst of the low L high B of acid.

Also may be used for process molecular sieve active component, or boehmite.

The preparation method of the acid catalyzed cracking catalyst of the low L high B of acid provided by the invention, boron element is incorporated in catalytic cracking catalyst, catalytic cracking catalyst Surface L acid content is reduced, B acid content improves, feed stock conversion can be improved as catalytic cracking micro-inverse time, effectively improve the yield of catalytically cracked gasoline, diesel oil, reduce lower carbon number hydrocarbons yield.

Accompanying drawing explanation

Fig. 1 is the XRD diffraction pattern of embodiment and comparative example gained sample;

Fig. 2 is the pyridine adsorption FTIR spectrogram of embodiment and comparative example gained sample.

Detailed description of the invention

The specific embodiment of the present invention is described in conjunction with the embodiments.

Embodiment 1

Get 20 grams of Industrial Catalysis Cracking catalyst, be labeled as M, join stirring to pulp in 50ml water.Then under 80 DEG C of water bath condition, add the BAS of the 0.65mol/L of 50ml, obtain the catalytic cracking catalyst suspension of acidifying, the reaction time keeps 0.5h.The dust technology adjust ph adding 1.0mol/L in gained mixture is again 3.0, continues successive reaction 24h under 80 DEG C of stirring in water bath conditions.Finally, by reacted sample suction filtration, washing, dry 8h at 110 DEG C, then roasting 4h at 500 DEG C, obtaining Product Labeling is sample A.

Embodiment 2

Get 20 grams of Y zeolites, be labeled as and be designated as N, add stirring to pulp in 50ml water.Then under 80 DEG C of water bath condition, add the BAS of the 0.65mol/L of 50ml, obtain the boehmite suspension of acidifying, reaction time 0.5h.The dust technology adjust ph adding 1.0mol/L in the mixture of gained is again 3.0, continues successive reaction 24h under 80 DEG C of stirring in water bath conditions.Finally, by reacted sample suction filtration, washing, dry 8h under 110 DEG C of conditions, then roasting 4h at 500 DEG C, obtain modified molecular screen sample B.

Embodiment 3

Get 20 grams of Y zeolites, be labeled as and be designated as N, impregnated in containing in 0.4g boron aqueous acid, left at room temperature 12h.Then by gained sample dry 8h at 80 DEG C, at 500 DEG C, roasting 4h obtains sample C.

Embodiment 4

Get 20 grams of boehmites and add stirring to pulp in 50ml water.Then under 80 DEG C of water bath condition, in mixed liquor, add the BAS of the 0.65mol/L of 50ml, obtain the boehmite suspension of acidifying, reaction 0.5h.The dust technology adjust ph adding 1.0mol/L is again 3.0, continues successive reaction 24h under 80 DEG C of stirring in water bath conditions.Finally, by reacted sample suction filtration, washing, dry 8h under 110 DEG C of conditions, then roasting 4h at 500 DEG C, obtain modified aluminas sample D.

Comparative example

By 20 grams of boehmites dry 8h under 110 DEG C of conditions, then at 500 DEG C, roasting 4h obtains common aluminium oxide comparative sample E.

The performance of above products therefrom detects, and gained testing result is in the specific area of table 1, aperture and pore volume data, the XRD diffraction pattern of Fig. 1 and the pyridine adsorption FTIR spectrogram of Fig. 2.

Specific area, aperture and pore volume data acquisition low temperature nitrogen physisorphtion measures (MicromereticsTristar3000).Measure the surface acid property of aluminium oxide with infra-red sepectrometry, adopt pyridine as absorption probe.

Table 1 specific area, aperture and pore volume testing result

Sample	Specific area S BET/(m 2/g)	Pore volume V/ (cm 3/g)
			A	155	0.192
B	607	0.385
			C	578	0.376
D	346	0.667
			E	304	0.680
M	144	0.193
			N	583	0.382

Above embodiment and comparative example products therefrom are used for catalytic cracking heavy oil anti-micro-, gained reaction result data, in table 2, can find out the catalytic cracking catalyst sample A that modification obtains, compared with before unmodified, light oil yield significantly improves, and liquefied gas and dry gas yied obviously reduce.

The micro-converse result of table 2 catalytic cracking heavy oil

Product/%	Sample M	Sample A
			Dry gas	2.08	1.28
Liquefied gas	16.40	10.21
			Hydrogen	0.15	0.07
Gasoline	41.47	47.72
			Diesel oil	24.01	25.11
Heavy oil	7.41	7.15
			Light oil yield	65.48	72.83
Coke	5.79	5.67
			Conversion ratio	89.86	89.99
Total liquid recovery	81.88	83.04

Claims (2)

1. the acid catalyzed cracking catalyst of the low L high B of acid, it is characterized in that, by following preparation method's gained, preparation method comprises the following steps:

(1) catalytic cracking catalyst is added in deionized water fully stir, under the bath temperature of 20-90 DEG C, add the BAS of 0.05-2.0mol/L, wherein H ₃bO ₃be 2% ~ 20% with the mass ratio of catalytic cracking catalyst;

(2) add inorganic acid in the mixed liquor obtained to step (1), regulate this mixed system pH value to be 2.0-6.0; Then successive reaction 0.5-24h in 20-90 DEG C of water-bath;

(3) gained mixture is filtered, washed, the filter cake of gained is dry at 50-200 DEG C, the roasting 2-24h at 500 DEG C-700 DEG C, obtains the acid catalyzed cracking catalyst of the low L high B of acid.

2. the acid catalyzed cracking catalyst of the low L high B of acid according to claim 1, it is characterized in that, the inorganic acid described in step (2) is one or more mixtures in hydrochloric acid, nitric acid, sulfuric acid.