CN103253684B - Method for synthesizing small-grain ZSM-5 molecular sieve by direct method in-situ crystallization - Google Patents

Abstract

The invention provides a method for preparing a ZSM-5 molecular sieve by direct in-situ crystallization without using a template agent. The method comprises the following steps: pretreating high-temperature roasted kaolin microspheres containing five-membered ring characteristic structural units by using water glass, adding acid to prepare a reaction mixture, and performing hydrothermal crystallization to obtain an in-situ product containing the ZSM-5 molecular sieve and an ex-situ ZSM-5 molecular sieve. The relative crystallinity of the kaolin microsphere in-situ crystallization ZSM-5 molecular sieve product prepared by the invention can be adjusted within 65% according to the needs, the grain size is 0.1-3 um, the wear resistance is good, and the kaolin microsphere in-situ crystallization ZSM-5 molecular sieve product can be used as a catalytic assistant for increasing the yield of propylene in the FCC process. The crystallinity of the co-produced ex-situ ZSM-5 molecular sieve can reach more than 90 percent, and the grain size is 0.1-3 um, so that the co-produced ex-situ ZSM-5 molecular sieve can be used for preparing a semi-synthetic catalyst.

Description

A kind of method of direct method in-situ crystallization synthesizing small crystal grain ZSM-5-5 molecular sieve

Technical field

The present invention relates to and a kind ofly adopt direct method, take kaolin microsphere as the method for raw material in-situ crystallization synthesizing small crystal grain ZSM-5-5 molecular sieve.

Background technology

ZSM-5 molecular sieve has the shape selective catalysis performance of unique three-dimensional open-framework, good hydrothermal stability and excellence because of it, is introduced in FCC catalyst, is used for improving octane number and increased low carbon olefine output.

In FCC catalyst, the introducing of active component generally has two kinds of modes, and active component and matrix, binding agent are mixed and made into slurries by the first, and spray-dried, roasting supervisor is prepared into microspherical catalyst, is called semi-synthetic catalyst; It two is first kaolin spraying is prepared into microballoon, after roasting, under suitable condition by the method for hydrothermal crystallizing by the growth of molecular sieve active component on kaolin microsphere (i.e. in-situ crystallization), be called in-situ crystallization or clay catalyst entirely.The full clay catalyst containing Y zeolite utilizing in-situ crystallization method to prepare demonstrates good performance in the activity stability, raising heavy oil transformation and preventing from heavy metal pollution ability etc. of raising molecular sieve, great success (Xu Chunming etc.: " petroleum refining and technical progress of chemical engineering " are industrially obtained, petroleum industry publishing house, 2006, Beijing, the first edition, 212-258 page).In recent years, the growing of propylene demand requires that in raising FCC catalyst, ZSM-5 selects the content of type molecular sieve, but, the mechanical strength of FCC technique to microspherical catalyst has strict requirement, there is the upper limit in molecular sieve content total in catalyst, increase ZSM-5 molecular sieve content and certainly will will reduce the content of other active component (as Y zeolite), therefore the activity of semisynthetic microspherical catalyst and heavy oil conversion performance all can be affected.The catalyst that in-situ crystallization technology obtains, its Active components distribution is on the outer surface or even internal channel surfaces of microballoon, and the accessibility of active component is better, and activity stability is high.The in-situ crystallization technology industrialization of Y zeolite, and ZSM-5 molecular sieve is as the main shape selective catalysis active component of another in FCC catalyst, its in-situ crystallization industrial production technology have not been reported.Therefore, in-situ crystallization ZSM-5-5 sieve technology causes the extensive concern of domestic and international scientific research personnel in recent years.

Lanzhou University's academic dissertation (Sun Shuhong: " kaolin microsphere in-situ crystallization synthetic ZSM-5 zeolite catalyst and sign, application " thereof, Lanzhou University Ph.D. Dissertation, 2006) reporting in n-butylamine is that template in-situ crystallization on kaolin microsphere has synthesized ZSM-5, and its relative crystallinity can reach 27%; This paper there was reported and synthesized in-situ crystallization ZSM-5-5 molecular sieve with alkali density kaolin microsphere without template.Wherein the latter is by the kaolin microsphere after 950 ~ 1000 DEG C of high-temperature roasting 1 ~ 6h, mix in the ratio of 1: 0.4: 5 with NaOH, water, at 95 DEG C of reaction 2h, reactant mixture after filtration, washing, dry, obtain the kaolin microsphere of alkali density modification; Again alkali density kaolin microsphere and ZSM-5 crystal seed are joined in the mixed system be made up of waterglass, aluminum sulfate, deionized water that (each constituent content is 20Na ₂oAl ₂o ₃60SiO ₂1100H ₂o), wherein, the addition of alkali density microballoon and the addition of ZSM-5 crystal seed be respectively sodium that in system, waterglass and aluminum sulfate provide, aluminium, one times and 2% of Si oxide gross weight, instillation 3M aqueous sulfuric acid regulates and reduces reactant mixture pH value, and then obtain at 150 DEG C of Water Under thermal crystallisation 48 ~ 96h the microballoon product that ZSM-5 molecular sieve content is 17%, also obtain the ZSM-5 molecular sieve fines product that a large amount of ex situs generates simultaneously.The technical characterstic of the method is the use of a part of active silica-alumina that highly basic NaOH solution extracts from kaolin microsphere, make to form certain duct in the body of microballoon, additional silicon and aluminum source again, ZSM-5 must be used as crystal seed simultaneously, finally can realize the in-situ crystallization synthesis of ZSM-5 molecular sieve.But utilize the step of NaOH alkali density kaolin microsphere only to reach the object of extracting kaolin microsphere, but employ extra alkali, and this part of alkali needed to filter, not only can produce discarded alkali lye and washes, also can increase the steps such as filtration, washing, make preparation technology become complicated; In addition, the active silica-alumina extracted from kaolin microsphere is in this course filtered after entering liquid phase and has washed away (not being utilized in crystallization system afterwards), is equivalent to a part of sial raw material and has been wasted; Moreover the crystallization time of the method is longer, need more than 48 hours, the product degree of crystallinity obtained is lower.

In addition, crystallization method is synthesized in ZSM-5 or Y zeolite process in position, the active silica-alumina in kaolin microsphere or additional sial can be dissolved in the liquid phase medium of alkalescence, this part sial material can not completely and kaolin microsphere interact and be all converted into in-situ crystallization molecular sieve (namely growing the molecular sieve on microballoon), but the molecular sieve (namely do not grow the molecular sieve on microballoon, be similar to the molecular sieve product that conventional hydrothermal crystallization obtains) of the ex situ generation that a part of crystallization is in the liquid phase formed can be generated.Generally the kaolin microsphere containing in-situ crystallization molecular sieve is called in-situ crystallization product, relative to the molecular sieve of growth in situ, liquid phase crystallization product is then called ex situ crystallization product.(Shen Jian Hua, Mao Xuewen, former good, the Zhang Yongming: " the non-in-situ crystallization reaction in kaolin microsphere fabricated in situ NaY zeolite system " such as Shen Jian Hua, petroleum journal (PETROLEUM PROCESSING), 1996,12 (4), 20 ~ 25) in the non-in-situ crystallization research of in-situ crystallization Y zeolite, relevant description has been carried out.(Lin Wei, Meng Ming, Zou Xubiao, the Qin Song: the research of " white powder " " in the kaolin in-situ crystallization process " such as Lin Wei, Industrial Catalysis, 2007,15 (8), 62 ~ 64) research of " white powder " in kaolin microsphere in-situ crystallization Y zeolite process is shown, in actual industrial production, also there is molecular sieve " white powder " product of quite a few ex situ.

CN101462740A discloses a kind of with through the kaolin microsphere of roasting and Silicon-rich clay microphere, the method for carrying out in-situ crystallization synthesis ZSM-5 molecular sieve.In the product obtained, the relative crystallinity of ZSM-5 molecular sieve is 30-90%, all needs to introduce expensive organic formwork agent in the building-up process of the wherein product of higher crystallinity.The method has also related to and added ZSM-5 crystal seed in the preparation process of kaolin microsphere, and in-situ crystallization synthesizes the example of ZSM-5 under the condition of not adding organic formwork agent, this example be by kaolin microsphere and solid sodium hydroxide with 1: 0.03 weight ratio mix after, roasting 2h at 918 DEG C.By Silicon-rich clay microphere and solid sodium hydroxide with 1: 0.05 weight ratio mix after, roasting 1h at 500 DEG C.Then get after 3.5g roasting kaolin microballoon and 32g roasting Silicon-rich clay microphere mix with sodium hydroxide solution and carry out in-situ crystallization, the product relative crystallinity obtained is 47%.But the method needs to carry out high-temperature process respectively to two kinds of microballoons, and technique is more complicated.For whether there will be the ex situ crystallization product reported in document in crystallization process, and physico-chemical property is not mentioned.

CN101332995A discloses a kind of method of modified kaolin microballoon in-situ crystallization ZSM-5-5 molecular sieve.The technical characterstic of the method is first mixed with modification constituent element by kaolin, is shaped, and mix with additional silicon and aluminum source, template, crystal seed, water after high-temperature roasting, hydrothermal crystallizing has synthesized kaolin based ZSM-5 molecular sieve.Its product relative crystallinity is 30 ~ 80%, introduces expensive organic amine as template and crystal seed in this crystallization system.

USP6908603 discloses one and neither uses organic formwork agent, does not also use ZSM-5 crystal seed, but needs to introduce Y molecular sieve seed-solution, situ synthesis of ZSM-5 method on kaolin microsphere.The technical characterstic of the method is the seed-solution introduced in the mixture systems such as kaolin microsphere, alkali and silicate after baking containing Y zeolite.

USP5145659 adopts clay matrix microspheres, adopts organic amine template method to synthesize ZSM-5 molecular sieve, after 200 mesh sieves screenings to in-situ crystallization ZSM-5-5 molecular sieve crystallinity can reach 35%, ex situ crystallization ZSM-5-5 molecular sieve crystallinity can reach 38%.One of feature of the method is the use of organic amine template.The method has also related to after kaolin, solid silicone and the hybrid shaping of ZSM-5 crystal seed, be shaped at 982 DEG C of roasting 3h, first at low temperature 100 DEG C, react 16h after mixing with water and NaOH, then at high temperature 149 DEG C crystallization 4 days, in the product obtained, ZSM-5 content is 40%.

EP0156595 technology is by after clay, silicon and aluminum source and high-silica zeolite crystal seed (as ZSM Series Molecules sieve) hybrid shaping, high-temperature roasting, then be mixed with aqueous slkali and meet the mixture that high-silica zeolite generates proportioning, after first low temperature aging, the mode of high temperature crystallization obtains the in-situ crystallization product that high-silica zeolite content can reach 60% again, and wherein high temperature crystallization time reaches 4 days.

King have and wait people (king have and etc.: the fabricated in situ of non-amine method ZSM-5 " on the kaolin microsphere ", Chinese Journal of Inorganic Chemistry, 2009,25 (3), after 533-538) roasting kaolin microballoon, silicic acid, NaOH, additional ZSM-5 crystal seed and water being stirred, direct fabricated in situ ZSM-5 molecular sieve on kaolin microsphere under without amine condition.The feature of the method needs to use crystal seed.Although in-situ crystallization ZSM-5-5 molecular sieve crystal grain utilizing the method to obtain is less, the specific area of product is less, only has 60m ²/ g, illustrates that in-situ crystallization is less to the amount of the ZSM-5 on kaolin microsphere, also can find out that the degree of crystallinity of in-situ crystallization product is lower from the XRD spectra that this report provides.This report does not mention the physico-chemical property of ex situ product.

In above-mentioned patent or document, the relative crystallinity of template agent method in-situ crystallization synthesis ZSM-5 molecular sieve is higher, but template itself is expensive, and pollute the environment in post processing removed template method process, high-temperature roasting method is often adopted to remove template in addition in industrial production, this needs energy consumption, and therefore the use of template certainly will increase the manufacturing cost of in-situ crystallization catalyst greatly, is the method that should as far as possible avoid; In above-mentioned patent or document, an other class is the method for in-situ crystallization ZSM-5-5 molecular sieve not using template, but all need to use such or such crystal seed, there is high, the not harsh pretreatment condition of technological process complexity, raw material availability, expensive silicon source, the weak points such as such or such crystal seed, crystallization time length must be used.And the key index such as relative crystallinity, specific area of kaolin microsphere in-situ crystallization ZSM-5-5 molecular sieve that these methods obtain is general not high, there is the problem that combined coefficient is low, and the performance and application of the ex situ ZSM-5 molecular sieve product produced in in-situ crystallization reaction is not taken in.

Summary of the invention

The invention provides a kind of method of direct method kaolin microsphere in-situ crystallization ZSM-5-5 molecular sieve, its feature is:

1. spraying dry after kaolin, waterglass, water mixing making beating is obtained kaolin microsphere, then obtain roasting kaolin microballoon through roasting.This roasting kaolin microballoon through infrared spectrum characterization, at 540 ~ 560cm ^-1there is the infrared vibration absworption peak of pentacyclic feature structure unit (about at 540 ~ 560cm in scope ^-1in scope, the report that infrared vibration absworption peak represents pentacyclic feature structure unit please be seen: Guo Wen silicon, hard etc.: " the infrared spectrum structural analysis of ZSM-5 type zeolite ", catalysis journal, 1981,2 (1): 36 ~ 41 pages; Xu Ruren, Pang Wenqin etc.: " molecular sieve and porous material chemistry ", Beijing, Science Press, 2004,172 pages; And Jacobs P A, Derouane E G, Weitkamp J.J.Chem.Soc.Chem.Commun.1981,591.).

In the present invention, the roasting of kaolin microsphere can adopt prior art, as roasting 0.1 ~ 10h under 500 ~ 1100 DEG C of high temperature, obtains roasting kaolin microballoon.Sintering temperature preferably 700 ~ 1000 DEG C, roasting time is 0.5 ~ 4h preferably.Can be different according to object, adopt different condition roasting microballoon, to be met the microspheres product of condition, as intensity, particle size etc.The condition of this roasting explores gained according to long-term pilot scale, can obtain the suitable microballoon raw material that this experiment needs within the scope of this roasting condition.

2. the pretreatment of roasting kaolin microballoon: by above-mentioned baked kaolin microsphere waterglass stirring reaction (i.e. pretreatment) 6 ~ 60h at 40 ~ 120 DEG C, preferably at 60 ~ 100 DEG C of pretreatment 12 ~ 36h.Wherein, OH in pretreatment mixed system ^-, H ₂the active SiO of O and roasting kaolin microballoon ₂amount calculate in molar ratio as OH ^-/ SiO ₂=0.3 ~ 3, OH ^-/ SiO ₂preferably 0.6 ~ 2.6.H ₂o/SiO ₂=10 ~ 120, H ₂o/SiO ₂preferably 30 ~ 90.Wherein, OH ^-for the OH in waterglass ^-, SiO ₂for the active SiO in the kaolin microsphere after roasting ₂, H ₂o is water whole in system.

Waterglass is adopted to carry out harsh pretreatment to roasting kaolin microballoon, its Main Function utilizes the silicon and aluminum source on sodium metasilicate in waterglass and poly sodium metasilicate and kaolin microsphere to interact, the state of the silicon and aluminum source on kaolin microsphere or composition are changed, thus is conducive to in-situ crystallization formation ZSM-5 molecular sieve.In addition, the main component Na of waterglass ₂siO ₃or the hydrolysis of polymeric silicicacid sodium solution can provide the OH that basicity is moderate and sustainable, stable ^-, OH ^-na is made with kaolin microsphere active silica-alumina component generation interaction ₂siO ₃hydrolyzed chemical balance moves to positive reaction direction, promotes Na again ₂siO ₃further hydrolysis.Directly OH is to the difference that kaolin microsphere processes with NaOH solution ^-be discharge gradually in the process of process, therefore make the basic pattern of kaolin microsphere not easily be destroyed in water glass solution processing procedure.Waterglass makes the active silica-alumina component in microballoon at the OH of slow releasing to the pretreatment that roasting kaolin microballoon carries out on the one hand ^-effect under can as much as possiblely just to adjust before crystallization starts, for crystallization ZSM-5-5 molecular sieve provides suitable silicon and aluminum source; On the other hand, the certain hole formed in microballoon spheroid after the restructuring of this part active silica-alumina substance dissolves, is conducive to the mass transfer of crystallization.The result of this effect is: under the inducing action of five-membered ring feature structure unit, not only grown fine and close interlaced ZSM-5 molecular sieve at kaolin microsphere surface crystallization, and the reactant in hole in its body also transforms in order to ZSM-5 molecular sieve, by the mode of chemical bond, the different blocks of kaolin spheroid is coupled together simultaneously, microballoon intensity is increased greatly, and anti-wear performance is improved.Dissolve the sial material entering liquid phase after entering crystallization stage, then react the ZSM-5 molecular sieve generating the ex situ of high-crystallinity.In other words, the path between the liquid phase sial needed for " five-membered ring " construction unit and in-situ crystallization ZSM-5-5 has been dredged in the pretreatment of water glass solution of synthesizing basicity higher than ZSM-5, the inducing action of " five-membered ring " construction unit is made to obtain better performance, facilitate again the generation of high-quality ex situ ZSM-5 molecular sieve simultaneously, improve the utilization rate of raw material greatly.

3. the preparation of in-situ crystallization initial reactant: with sour regulation system basicity (i.e. OH ^-/ SiO ₂) to 0.12 ~ 0.20, make reactant mixture, wherein each component by the mol ratio of its oxide basis is:

SiO ₂/ Al ₂o ₃=25 ~ 80, preferably 35 ~ 65;

OH ^-/ SiO ₂=0.12 ~ 0.20, preferably 0.14 ~ 0.18;

H ₂o/SiO ₂=10 ~ 80, preferably 20 ~ 50;

SiO in the mol ratio of above-mentioned reactant mixture ₂comprise the active SiO in the kaolin microsphere after roasting ₂with the SiO in waterglass ₂, Al ₂o ₃for the active A l in the kaolin microsphere after roasting ₂o ₃.

4. carry out the in-situ crystallization of ZSM-5, after crystallization completes, then through sedimentation separation in water, washing, filtration, dry obtained in-situ crystallization ZSM-5-5 molecular sieve and ex situ ZSM-5 molecular sieve.Its condition can adopt the general conditions of prior art, and as gained reactant mixture is carried out hydrothermal crystallizing 6 ~ 48h at 140 ~ 200 DEG C, crystal pattern can be static, dynamic or batch (-type) dynamic crystallization.

A kind of direct method in-situ crystallization provided by the invention prepares the method for ZSM-5 molecular sieve, can comprise following process more specifically:

(1) preparation of roasting kaolin microballoon: kaolin, waterglass and water are mixed and made into slurries, then slurries by the shaping microballoon making 10 ~ 210um of spray-dired method.In above-mentioned slurries, the butt amount of waterglass is 1 ~ 10wt% of kaolin quality (butt), preferably 4 ~ 7wt%, and the solid content of slurries is 10 ~ 60wt%.

Also can add molecular sieve crystal seed to above-mentioned mixed serum, crystal seed can be one or more in ZSM-5 type, Y type and Beta type molecular sieve, and preferred ZSM-5 crystal seed, the addition of crystal seed accounts for SiO in kaolin ₂0 ~ 10wt% of quality.But add crystal seed not necessarily.Also expanding agent can be added again in above-mentioned kaolin microsphere preparation process, described expanding agent the present invention is not particularly limited, the expanding agent can commonly used for in-situ crystallization molecular sieve, as being one or more in starch, oxidized starch, graft starch, acid treated starches, polyacrylamide, by butt Mass Calculation, expanding agent accounts for SiO in kaolin ₂0 ~ 10wt% of quality.

In the kaolin microsphere made, kaolin amount (butt) is preferably 75% ~ 96wt% of microballoon gross mass (butt).

Roasting the present invention of kaolin microsphere is not limited especially, adopts prior art.

Suggestion uses following roasting condition: by this kaolin microsphere roasting 0.1 ~ 10h under 500 ~ 1100 DEG C of high temperature, obtain roasting kaolin microballoon.Sintering temperature preferably 700 ~ 1000 DEG C, roasting time is 0.5 ~ 4h preferably.Use the method roasting kaolin microballoon can obtain pentacyclic feature structure unit.Do not get rid of the method using other can obtain the roasting kaolin microballoon of pentacyclic feature structure unit in the present invention.

(2) pretreatment of roasting kaolin microballoon: by above-mentioned baked kaolin microsphere waterglass stirring reaction (i.e. pretreatment) 6 ~ 60h at 40 ~ 120 DEG C, preferably at 60 ~ 100 DEG C of pretreatment 12 ~ 36h.Wherein, OH in pretreatment mixed system ^-, H ₂the active SiO of O and roasting kaolin microballoon ₂amount calculate in molar ratio as OH ^-/ SiO ₂=0.3 ~ 3, preferably 0.6 ~ 2.6, H ₂o/SiO ₂=10 ~ 120, preferably 30 ~ 90.Wherein, OH ^-for the OH in waterglass ^-, SiO ₂for the active SiO in the kaolin microsphere after roasting ₂, H ₂o is water whole in system.

(3) preparation of in-situ crystallization initial reactant: with sour regulation system basicity (i.e. OH ^-/ SiO ₂) to 0.12 ~ 0.20, make reactant mixture, wherein each component by the mol ratio of its oxide basis is:

SiO ₂/ Al ₂o ₃=25 ~ 80, preferably 35 ~ 65;

OH ^-/ SiO ₂=0.12 ~ 0.20, preferably 0.14 ~ 0.18;

H ₂o/SiO ₂=10 ~ 80, preferably 20 ~ 50;

SiO in the mol ratio of above-mentioned reactant mixture ₂comprise the active SiO in the kaolin microsphere after roasting ₂with the SiO in waterglass ₂, Al ₂o ₃for the active A l in the kaolin microsphere after roasting ₂o ₃.

Sour the present invention wherein used is not particularly limited, and is the acid that the art is general, as being one or more in sulfuric acid, hydrochloric acid and nitric acid.

(4) in-situ crystallization of ZSM-5: carry out hydrothermal crystallizing 6 ~ 48h at 140 ~ 200 DEG C to gained reactant mixture, crystal pattern can be static, dynamic or batch (-type) dynamic crystallization.Crystallization temperature preferably 150 ~ 180 DEG C, crystallization time is 8 ~ 36h preferably.

After crystallization completes, then through sedimentation separation, washing, filtration, dry obtained in-situ crystallization ZSM-5-5 molecular sieve and ex situ ZSM-5 molecular sieve.

According to the method that the present invention proposes, the composition of kaolin microsphere must meet the ratio of kaolin of the present invention and waterglass, otherwise the roasting kaolin microballoon obtained does not possess five-membered ring feature structure unit.

In the present invention, the active SiO of roasting kaolin microballoon ₂, active A l ₂o ₃assay method be method therefor in prior art, periodical literature all has report, as Zheng Shuqin, Chang little Ping, high rich etc.: " in kaolin in-situ crystallization system roasting microballoon characteristic research ", nonmetallic ore, 2002,11 (6), 5-7 pages.

According to the method that the present invention proposes, on kaolin microsphere, the size of microcrystal of in-situ crystallization gained ZSM-5 molecular sieve is less than 5 microns, optimization be that the size of microcrystal of molecular sieve is less than 3 microns, optimized is that the size of microcrystal of molecular sieve is less than 1 micron.The relative crystallinity of gained in-situ crystallization product ZSM-5 molecular sieve can within 65%.

According to the method for direct method in-situ crystallization ZSM-5-5 molecular sieve provided by the invention, at waterglass in the preprocessing process of roasting kaolin microballoon, if degree for the treatment of is too low, then in microballoon silicon and aluminum source and waterglass effect inadequate, the time of crystallization will be extended and weaken the intensity of in-situ crystallization microballoon product, or cause in-situ crystallization and ex situ crystallization product to reduce, even there is stray crystal; If degree for the treatment of is too high, the sial component of dissolving in microballoon is too much, its kaolin microsphere will be made again broken, cause the reduction of in-situ crystallization product yield, even occur stray crystal.Therefore, degree for the treatment of should be suitable.Degree for the treatment of mentioned here refers to OH in pretreatment system ^-/ SiO ₂with pretreatment time, temperature, should control in the scope of application claims.

The invention provides a kind of method of direct method in-situ crystallization ZSM-5-5 molecular sieve, by kaolin microsphere prepared by this method, five-membered ring structure unit containing the feature required for crystallization ZSM-5-5 (this five-membered ring structure unit is crystal seed required for ZSM-5 crystallization or directed agents), no longer can add any organic formwork agent and any crystal seed, just can crystallization synthesis within a short period of time ZSM-5.In addition, the present invention proposes a kind of kaolin microsphere preprocess method of novelty, namely utilize in-situ crystallization to synthesize the cheap raw material waterglass of ZSM-5 molecular sieve to process kaolin microsphere, do not need additionally to use other alkaline solution.That is kaolin microsphere preprocess method provided by the invention is the use of a kind of raw material (waterglass) as cheap silicon source that follow-up in-situ crystallization synthesis ZSM-5 needs to use, just by the change of charging sequence, avoid the step using strong base solution process kaolin microsphere, it also avoid filtration, wash the operation of corresponding alkali lye, avoid the generation of relevant waste liquid.About in the patent of the in-situ crystallization of ZSM-5 and document disclosed in, the preparation of initial reaction mixture is by silicon source mostly, aluminium source and alkali source mix, control mixed system basicity in the claimed range of synthesis ZSM-5 after carry out crystallization immediately, and about higher than ZSM-5 synthesize basicity condition under pretreatment is carried out to kaolin microsphere after, not washing and filtering, after then entering into the crystallization stage of ZSM-5, make the sial substance be dissolved down from microballoon participate in the crystallization of ex situ simultaneously, the technology obtaining the ZSM-5 molecular sieve of high-quality ex situ have not been reported.

Utilize method provided by the present invention, with the kaolin microsphere containing five-membered ring feature structure unit for silicon and aluminum source, cheap waterglass is used to be alkali source and supplementary silicon source, any organic formwork agent or crystal seed can not be added, with cheap cost and simple and direct synthesis technique, in shorter crystallization time, obtain the kaolin microsphere in-situ crystallization product containing the ZSM-5 molecular sieve with small crystal grains of high-crystallinity and ex situ ZSM-5 molecular sieve simultaneously, and the specific area of in-situ crystallization microspheres product is large, pore structure is flourishing, anti-wear performance is good.Achieve the synchronous high-efficiency synthesis of high-quality in-situ ZSM-5-5 microspherical catalyst and powdery ex situ ZSM-5 molecular sieve, there are good commercial Application potentiality.

Accompanying drawing explanation

Figure 1 shows that the XRD spectra of synthesized original position microballoon product and ex situ powdered product in the embodiment of the present invention 6.

Figure 2 shows that the SEM figure of synthesized original position microballoon product in the embodiment of the present invention 6.

SEM spectrogram after one of them the microballoon product that Figure 3 shows that in Fig. 2 amplifies.

Figure 4 shows that the SEM figure of synthesized ex situ powdered product in the embodiment of the present invention 6.

Figure 5 shows that the raw material microballoon of the embodiment of the present invention 4 and comparative example 4 and the product microballoon infrared vibration spectrogram of embodiment 4.The product microballoon of a-in-situ crystallization ZSM-5-5 in figure, b-is containing pentacyclic raw material microballoon, and c-is containing containing pentacyclic raw material microballoon.

Detailed description of the invention

Below in conjunction with embodiment, the present invention is further detailed.

In an embodiment, said relative crystallinity is the ratio (representing with percentage) of the peak area sum of five characteristic diffraction peaks of 2 θ (2theta) between 22.5 ~ 25.0 ° of X-ray diffraction (XRD) spectrogram of products therefrom and ZSM-5 molecular sieve standard specimen.Standard specimen ZSM-5 molecular sieve is the H type ZSM-5 molecular sieve of the high-quality that Nankai University produces, and its degree of crystallinity is decided to be 95%.

The specific area related to herein characterizes the ASAP2020M type physical adsorption appearance using Micromeritic company of the U.S. to produce and measures product specific surface by nitrogen adsorption desorption.Calculate total specific area by BET method, calculate micro pore volume by t-plot method.Nitrogen adsorption assay condition: under liquid nitrogen temperature, isothermal adsorption desorption measures.

The active SiO of kaolin microsphere ₂, active A l ₂o ₃composition measuring method is as follows:

Active SiO in kaolin microsphere ₂method of testing: on industrial balance, take sample 5.000 ± 0.01g, be placed in 100mL conical flask, then add 25mL, the sodium hydroxide solution of 15%, shakes up, and is placed in 80 DEG C of waters bath with thermostatic control, extracting 1h, and every 5min shake is once.Terminate rear filtered on buchner funnel, mother liquor is all collected in 250mL volumetric flask.Finally be diluted to scale with 0.5mol/L sodium hydroxide solution.The filtrate 10mL tried to please in measuring bottle with pipette, in white plastic bottle, adds red fuming nitric acid (RFNA) 10mL in fume hood, adds solid potassium chloride 2 ~ 3g, after it dissolves, is cooled to room temperature, adds 15% potassium fluoride solution 10mL, stirs and makes its complete reaction.Filter with fast grade filter paper and plastic funnel, then wash filter paper and plastic cup three times with 5% Klorvess Liquid.Precipitation is moved in former plastic cup together with filter paper, add the potassium chloride alcoholic solution 10mL of 5%, phenolphthalein indicator 10, the acid do not cleaned carefully is neutralized with 0.2500mol/L sodium hydroxide solution, careful stirring filter paper and precipitation are until redden, then add the boiling water of about 200mL, be titrated to blush with 0.2500mol/L NaOH standard liquid immediately, 30s fades inside for titration end-point. ${\mathrm{SiO}}_2(m/m)=\frac{C_{\mathrm{NaOH}}\×V_{\mathrm{NaOH}}\×\frac{60}{4}\×F}{1000\×m}\×100$

In formula: m-sample weight

C _naOHthe concentration of-standardised sodium hydroxide, 0.2500mol/L

V _naOHthe volume of-standardised sodium hydroxide consumes number, Ml

SiO ₂the percentage composition of %-active silica

F-dilutes the multiple of main liquid.

Active A l in kaolin microsphere ₂o ₃method of testing: take 5g sample and put into 250mL conical flask, add 6mol/L hydrochloric acid solution 36.8mL, put into 80 DEG C of waters bath with thermostatic control, extracting 80min.Filter, once wash three times respectively with the 0.5mol/L hydrochloric acid solutions of 60 DEG C, finally filtrate is collected in 250mL volumetric flask, constant volume post analysis alumina content.Get above solution 10.00mL in conical flask, add the xylenol orange indicator of 2mL aqueous tartaric acid solution, 10mLEDTA standard liquid and about 15mg, ammoniacal liquor with 1: 1 regulates solution to be aubergine, 1: 1 hydrochloric acid is used to be adjusted to yellow again, with buffer solution 15mL, with the EDTA that the standard chlorination zinc solution back titration of 0.05000mol/L is excessive, volumetric soiutions goes out yellow and becomes redness and be terminal, the volume that several lower zinc chloride standard liquid consumes.

Activated alumina computing formula is as follows:

${\mathrm{Al}}_2{O}_3=\frac{(M_1{V}_1-M_2{V}_2)\×F\×51}{1000\×G}\×100\%$

M ₁the concentration of-EDTA standard liquid, mol/L

V ₁the volume of-EDTA standard liquid, mL

M ₂-ZnCl ₂the concentration of standard liquid, mol/L

V ₂-consume ZnCl ₂the volume of standard liquid, mL

F-divides the multiple getting network analysis liquor capacity

G-takes the weight of kaolin ball, g

The conversion coefficient of 51-aluminium oxide

Described herein " situ product " is the kaolin crystallization microballoon containing molecular sieve, and relative to the molecular sieve of growth in situ, liquid phase crystallization product is then called " ex situ product ".

Situ product described herein and the separation method of ex situ product can use the combination of one or more of sedimentation separation in the method for screening, the method for cyclonic separation or water.The method of sedimentation separation in water is used in embodiment, the method is: after crystallization terminates, product is poured in beaker, add appropriate water, after stirring, leave standstill 2 minutes, because the product microballoon of original position wants fast a lot of compared with the sinking speed of the fine powder of ex situ, pour out the ex situ molecular sieve fine powder of the non-sedimentation in upper strata.Repeat above lock out operation 2 ~ 3 times, time of repose is shortened to 1 minute, pour out upper suspension, time of repose is afterwards 30 seconds, in the process of sedimentation separation, the liquid on upper strata can be limpid gradually, till the clear liquid on upper strata in 30 seconds is completely limpid, namely isolates the ZSM-5 molecular sieve of ex situ and original position completely.

Embodiment 1

The preparation of kaolin microsphere:

Spraying dry after 3071g kaolin, 536g waterglass and 5002g distilled water mixing making beating is made the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 2h at 950 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 40.0wt%, active A l ₂o ₃content 5.95wt%.Kaolin microsphere is analyzed through IR, at 550cm ^-1near there is five-membered ring eigen vibration absworption peak.

In-situ crystallization ZSM-5-5 molecular sieve:

Take 30.0g roasting kaolin microballoon and 131.1g distilled water in beaker, beaker is put into 90 DEG C of water-baths, stir 5min; In beaker, add 111.1g waterglass, stir 20h; Then add 131.1g distilled water, after stirring 10min, in system, slowly add 36.1g 3M sulfuric acid solution regulation system basicity; Continue to stir 1h after adding sulfuric acid solution, uniform reactant mixture will be obtained.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=41, OH ^-/ SiO ₂=0.18, H ₂o/SiO ₂=28; Mixture is transferred in 1L stainless steel autoclave in 180 DEG C of standing crystallization 24h.After reaction terminates, product obtains the said situ product of the present invention and ex situ product through separation, washing, filtration, drying and other steps.Show that two kinds of products all have the characteristic diffraction peak of ZSM-5 molecular sieve through XRD analysis.

By the NH of above-mentioned situ product and 0.5mol/L ₄cl solution is 1: 5 mixing in mass ratio, stirs 1h, repeat 2 times at 90 DEG C, and washing, filtration, drying obtain ammonium type product, obtain H type product after 540 DEG C of roasting 4h.

Embodiment 2

The preparation of kaolin microsphere:

Spraying dry after 2752g kaolin, 263g waterglass and 4698g distilled water mixing making beating is made the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 2h at 950 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 40.2wt%, active A l ₂o ₃content 5.92wt%.Kaolin microsphere is analyzed through IR, at 550cm ^-1near there is five-membered ring eigen vibration absworption peak.

In-situ crystallization ZSM-5-5 molecular sieve:

Take 30.0g roasting kaolin microballoon and 300.0g distilled water in beaker, beaker is put into 60 DEG C of water-baths, stir 5min; In beaker, add 282.0g waterglass, stir 20h; Then add 300.0g distilled water, after stirring 10min, in system, slowly add 59.0g 3M sulfuric acid solution regulation system basicity; Continue to stir 1h after adding sulfuric acid solution, uniform reactant mixture will be obtained.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=60, OH ^-/ SiO ₂=0.20, H ₂o/SiO ₂=40; Mixture is transferred in 1L stainless steel autoclave in 170 DEG C of standing crystallization 24h.After reaction terminates, product obtains the said situ product of the present invention and ex situ product through separation, washing, filtration, drying and other steps.Show that two kinds of products all have the characteristic diffraction peak of ZSM-5 molecular sieve through XRD analysis.

The NH4Cl solution of above-mentioned situ product and 0.5mol/L to be mixed in mass ratio at 1: 5, at 90 DEG C, stirs 1h, repeat 2 times, washing, filter, drying obtains ammonium type product, obtains H type product after 540 DEG C of roasting 4h.

Embodiment 3

The preparation of kaolin microsphere:

Spraying dry after 3012g kaolin, 780g waterglass and 6206g distilled water mixing making beating is made the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 2h at 950 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 41.2wt%, active A l ₂o ₃content 5.7wt%.Kaolin microsphere is analyzed through IR, at 550cm ^-1near there is five-membered ring eigen vibration absworption peak.

In-situ crystallization ZSM-5-5 molecular sieve:

Take 30.0g roasting kaolin microballoon and 55.0g distilled water in beaker, beaker is put into 70 DEG C of water-baths, stir 5min; In beaker, add 70.0g waterglass, stir 24h; Then add 55.0g distilled water, after stirring 10min, in system, slowly add 24.0g 3M sulfuric acid solution regulation system basicity; Continue to stir 1h after adding sulfuric acid solution, uniform reactant mixture will be obtained.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=30, OH ^-/ SiO ₂=0.14, H ₂o/SiO ₂=18; Mixture is transferred in 0.5L stainless steel autoclave in 180 DEG C of standing crystallization 24h.After reaction terminates, product obtains the said situ product of the present invention and ex situ product through separation, washing, filtration, drying and other steps.Show that two kinds of products all have the characteristic diffraction peak of ZSM-5 molecular sieve through XRD analysis.

By the NH of above-mentioned situ product and 0.5mol/L ₄cl solution is 1: 5 mixing in mass ratio, stirs 1h, repeat 2 times at 90 DEG C, and washing, filtration, drying obtain ammonium type product, obtain H type product after 540 DEG C of roasting 4h.

Embodiment 4

The preparation of kaolin microsphere:

By 30.71kg kaolin, 1.99kg ZSM-5 molecular sieve crystal seed, 5.36kg waterglass and 50.02kg distilled water mixing making beating, spraying dry makes the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 2.5h at 950 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 40.8wt%, active A l ₂o ₃content 5.6wt%.Kaolin microsphere is analyzed through IR, at 550cm ^-1near there is five-membered ring eigen vibration absworption peak.

In-situ crystallization ZSM-5-5 molecular sieve:

Taking 16.000kg distilled water joins in 100L autoclave, adds 3.452kg kaolin microsphere under stirring; Heat up, after reaching 90 DEG C to temperature in the kettle, add 17.192kg waterglass wherein, at 90 DEG C, stir 20h; Then add 16.000kg distilled water, after stirring 15min, in system, add 6.214kg 3M sulfuric acid solution regulation system basicity, after adding sulfuric acid solution, make reactant mixture.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=55, OH ^-/ SiO ₂=0.16, H ₂o/SiO ₂=25; Sealed reactor, Keep agitation crystallization 20h after being warming up to 180 DEG C.After reaction terminates, product obtains the said situ product of the present invention and ex situ product through separation, washing, filtration, drying and other steps.Two kinds of products show the characteristic diffraction peak all with ZSM-5 molecular sieve through XRD analysis.

By the NH of above-mentioned situ product and 0.5mol/L ₄cl solution is 1: 5 mixing in mass ratio, stirs 1h, repeat 2 times at 90 DEG C, and washing, filtration, drying obtain ammonium type product, and 540 DEG C of roasting 4h obtain H type product.

Embodiment 5

The preparation of kaolin microsphere:

By 3071g kaolin, 199g ZSM-5 molecular sieve crystal seed, 536g waterglass and 5002g distilled water mixing making beating, spraying dry makes the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 4h at 850 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 37.5wt%, active A l ₂o ₃content 4wt%.

In-situ crystallization ZSM-5-5 molecular sieve:

Take 40.0g kaolin microsphere and 278.0g distilled water in beaker, beaker is put into 95 DEG C of water-baths, stir 5min; In beaker, add 148.0g waterglass, stir 17h; Then add 278.0g distilled water, after stirring 10min, in system, add 56.0g 3M sulfuric acid solution regulation system basicity; Continue to stir 40min after adding sulfuric acid solution and make reactant mixture.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=60, OH ^-/ SiO ₂=0.14, H ₂o/SiO ₂=41; Mixture is transferred in autoclave in 180 DEG C of standing crystallization 30h.After reaction terminates, product obtains the said in-situ crystallization of the present invention and ex situ product through separation, washing, filtration, drying.Two kinds of products show the characteristic diffraction peak all with ZSM-5 molecular sieve through XRD analysis.

By the NH of above-mentioned situ product and 0.5mol/L ₄cl solution is 1: 5 mixing in mass ratio, stirs 1h, repeat 2 times at 90 DEG C, and washing, filtration, drying obtain ammonium type product, and 540 DEG C of roasting 4h obtain H type product.

Embodiment 6

The preparation of kaolin microsphere:

3071g kaolin, 536g waterglass and 5002g distilled water mixing making beating, spraying dry are made the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 2.5h at 950 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 40.0wt%, active A l ₂o ₃content 5.95wt%.Kaolin microsphere is analyzed through IR, at 550cm ^-1near there is five-membered ring eigen vibration absworption peak.

In-situ crystallization ZSM-5-5 molecular sieve:

Take 25.0g kaolin microsphere and 113.0g distilled water in beaker, beaker is put into 90 DEG C of water-baths, stir 5min; In beaker, add 124.0g waterglass, stir 22h; Then add 113.0g distilled water, after stirring 10min, in system, add 42.5g 3M sulfuric acid solution regulation system basicity; Continue to stir 40min after adding sulfuric acid solution and make reactant mixture.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=51, OH ^-/ SiO ₂=0.17, H ₂o/SiO ₂=25; Mixture is transferred in autoclave, the autoclave after sealing is put into rotary oven in 160 DEG C of dynamic crystallization 36h.After reaction terminates, product obtains the said in-situ crystallization of the present invention and ex situ product through separation, washing, filtration, drying.Two kinds of products show the characteristic diffraction peak with ZSM-5 molecular sieve through XRD analysis.

By the NH of above-mentioned situ product and 0.5mol/L ₄cl solution is 1: 5 mixing in mass ratio, stirs 1h, repeat 2 times at 90 DEG C, and washing, filtration, drying obtain ammonium type product, and 540 DEG C of roasting 4h obtain H type product.

Embodiment 7

The preparation of kaolin microsphere:

5833g kaolin, 357g Beta molecular sieve crystal seed, 623g waterglass and 5833g water mixing making beating, spraying dry are made the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 2h at 1000 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 42wt%, active A l ₂o ₃content 3wt%.

In-situ crystallization ZSM-5-5 molecular sieve:

Take 26.0g kaolin microsphere and 130.0g distilled water in beaker, beaker is put into 90 DEG C of water-baths, stir 5min; In beaker, add 50.0g waterglass, stir 20h; Then add 130.0g distilled water, after stirring 10min, in system, add 13.0g 3M sulfuric acid solution regulation system basicity; Continue to stir 40min after adding sulfuric acid solution and make reactant mixture.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=54, OH ^-/ SiO ₂=0.18, H ₂o/SiO ₂=40; Mixture is transferred in autoclave, the autoclave after sealing is put into rotary oven in 180 DEG C of dynamic crystallization 28h.After reaction terminates, product obtains the said situ product of the present invention and ex situ product through separation, washing, filtration, drying and other steps.Two kinds of products show the characteristic diffraction peak with ZSM-5 molecular sieve through XRD analysis.

By the NH of above-mentioned situ product and 0.5mol/L ₄cl solution is 1: 5 mixing in mass ratio, stirs 1h, repeat 2 times at 90 DEG C, and washing, filtration, drying obtain ammonium type product, and 540 DEG C of roasting 4h obtain H type product.

Embodiment 8

The preparation of kaolin microsphere:

2047g kaolin, 250g Y zeolite crystal seed, 357g waterglass and 3335g water mixing making beating, spraying dry are made the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 6h at 750 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 34.0wt%, active A l ₂o ₃content 2.7wt%.

In-situ crystallization ZSM-5-5 molecular sieve:

Take 25.0g kaolin microsphere and 113.0g distilled water in beaker, beaker is put into 90 DEG C of water-baths, stir 5min; In beaker, add 32.0g waterglass, stir 22h; Then add 113.0g distilled water, after stirring 10min, in system, add 6.8g 3M sulfuric acid solution regulation system basicity; Continue to stir 40min after adding sulfuric acid solution and make reactant mixture.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=44, OH ^-/ SiO ₂=0.19, H ₂o/SiO ₂=48; Mixture is transferred in autoclave, the autoclave after sealing is put into rotary oven in 170 DEG C of dynamic crystallization 30h.After reaction terminates, product obtains the said in-situ crystallization of the present invention and ex situ product through separation, washing, filtration, drying.Two products show the characteristic diffraction peak with ZSM-5 molecular sieve through XRD analysis.

By the NH of above-mentioned situ product and 0.5mol/L ₄cl solution is 1: 5 mixing in mass ratio, stirs 1h, repeat 2 times at 90 DEG C, and washing, filtration, drying obtain ammonium type product, and 540 DEG C of roasting 4h obtain H type product.

Embodiment 9

The preparation of kaolin microsphere:

By 3.071kg kaolin, 0.199kg ZSM-5 molecular sieve crystal seed, 0.536g waterglass, 0.440g graft starch and 6.002kg distilled water mixing making beating, spraying dry makes the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 2.5h at 950 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 40.8wt%, active A l ₂o ₃content 5.6wt%.Kaolin microsphere is analyzed through IR, at 550cm ^-1near there is five-membered ring eigen vibration absworption peak.

In-situ crystallization ZSM-5-5 molecular sieve:

Taking 8.000kg distilled water joins in 50L autoclave, adds 1.726kg kaolin microsphere under stirring; Heat up, after reaching 90 DEG C to temperature in the kettle, add 8.596kg waterglass wherein, at 90 DEG C, stir 20h; Then add 8.000kg distilled water, after stirring 15min, in system, add 3.107kg 3M sulfuric acid solution regulation system basicity, after adding sulfuric acid solution, make reactant mixture.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=55, OH ^-/ SiO ₂=0.16, H ₂o/SiO ₂=25; Sealed reactor, Keep agitation crystallization 20h after being warming up to 180 DEG C.After reaction terminates, product obtains the said situ product of the present invention and ex situ product through separation, washing, filtration, drying and other steps.Two kinds of products show the characteristic diffraction peak all with ZSM-5 molecular sieve through XRD analysis.

By the NH of above-mentioned situ product and 0.5mol/L ₄cl solution is 1: 5 mixing in mass ratio, stirs 1h, repeat 2 times at 90 DEG C, and washing, filtration, drying obtain ammonium type product, and 540 DEG C of roasting 4h obtain H type product.

Embodiment 10

The preparation of kaolin microsphere:

By 3.071kg kaolin, 0.199kg ZSM-5 molecular sieve crystal seed, 0.536g waterglass, 0.320g polyacrylamide and 6.002kg distilled water mixing making beating, spraying dry makes the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 2.5h at 950 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 40.8wt%, active A l ₂o ₃content 5.6wt%.Kaolin microsphere is analyzed through IR, at 550cm ^-1near there is five-membered ring eigen vibration absworption peak.

In-situ crystallization ZSM-5-5 molecular sieve:

Taking 8.000kg distilled water joins in 50L autoclave, adds 1.726kg kaolin microsphere under stirring; Heat up, after reaching 90 DEG C to temperature in the kettle, add 8.596kg waterglass wherein, at 90 DEG C, stir 20h; Then add 8.000kg distilled water, after stirring 15min, in system, add 3.107kg 3M sulfuric acid solution regulation system basicity, after adding sulfuric acid solution, make reactant mixture.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=55, OH ^-/ SiO ₂=0.16, H ₂o/SiO ₂=25; Sealed reactor, Keep agitation crystallization 20h after being warming up to 180 DEG C.After reaction terminates, product obtains the said situ product of the present invention and ex situ product through separation, washing, filtration, drying and other steps.Two kinds of products show the characteristic diffraction peak all with ZSM-5 molecular sieve through XRD analysis.

By the NH of above-mentioned situ product and 0.5mol/L ₄cl solution is 1: 5 mixing in mass ratio, stirs 1h, repeat 2 times at 90 DEG C, and washing, filtration, drying obtain ammonium type product, and 540 DEG C of roasting 4h obtain H type product.

Comparative example 1

The preparation of kaolin microsphere:

By 3071g kaolin, 199g ZSM-5 molecular sieve crystal seed, 536g waterglass and 5002g distilled water mixing making beating, spraying dry makes the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 2h at 950 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 40wt%, active A l ₂o ₃content 6wt%.

In-situ crystallization ZSM-5-5 molecular sieve:

Take 25.0g kaolin microsphere, 124.0g waterglass and 226.0g distilled water in beaker, beaker is put into 70 DEG C of water-baths, stir 10min, mix; Then in system, add 43.0g 3M sulfuric acid solution regulation system basicity; Continue to stir 40min after adding sulfuric acid solution and make reactant mixture.In this reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=51, OH ^-/ SiO ₂=0.17, H ₂o/SiO ₂=25; Mixture is transferred in autoclave, the autoclave after sealing is put into baking oven in 180 DEG C of static crystallization 24h.After reaction terminates, product obtains the said in-situ crystallization of the present invention and ex situ product through separation, washing, filtration, drying.This product shows the characteristic diffraction peak with ZSM-5 molecular sieve through XRD analysis.Scanning electron microscope analysis shows that the crystal grain of ZSM-5 in this product is comparatively large, at about 15um.

By the NH of above-mentioned situ product and 0.5mol/L ₄cl solution is 1: 5 mixing in mass ratio, stirs 1h, repeat 2 times at 90 DEG C, and washing, filtration, drying obtain ammonium type product, and 540 DEG C of roasting 4h obtain H type product.

Comparative example 2

The preparation of kaolin microsphere:

The mixing of 3071g kaolin, 536g waterglass and 5002g distilled water is pulled an oar as solid content is the slurries of 34wt%, this slurries spraying dry is made the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 2h at 980 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 40wt%, active A l ₂o ₃content 4wt%.

In-situ crystallization ZSM-5-5 molecular sieve:

Take 20g kaolin microsphere, 2.6g NaOH and 300g distilled water in beaker, stir 10min, add 59g Ludox and 2.5g ZSM-5 molecular sieve crystal seed; Reactant mixture is made after mixing.In this reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=42, OH ^-/ SiO ₂=0.20, H ₂o/SiO ₂=59; Mixture is transferred in autoclave, the autoclave after sealing is put into baking oven in 160 DEG C of static crystallization 48h.After reaction terminates, product obtains the said in-situ crystallization of the present invention and ex situ product through separation, washing, filtration, drying.This product shows the characteristic diffraction peak with ZSM-5 molecular sieve through XRD analysis.

By the NH of above-mentioned situ product and 0.5mol/L ₄cl solution is 1: 5 mixing in mass ratio, stirs 1h, repeat 2 times at 90 DEG C, and washing, filtration, drying obtain ammonium type product, and 540 DEG C of roasting 4h obtain H type product.

Comparative example 3

Kaolinic preparation:

By former for 1000g kaolin powder roasting 2h at 950 DEG C, obtain the kaolin after roasting.This roasting kaolin is analyzed through IR, at 550cm ^-1near there is not five-membered ring eigen vibration absworption peak.

With above-mentioned roasting kaolin for Material synthesis ZSM-5 molecular sieve:

Take 30.0g roasting kaolin and 131.1g distilled water in beaker, beaker is put into 90 DEG C of water-baths, stir 5min; In beaker, add 111.1g waterglass, stir 20h; Then add 131.1g distilled water, after stirring 10min, in system, slowly add 36.1g 3M sulfuric acid solution regulation system basicity; Continue to stir 1h after adding sulfuric acid solution, uniform reactant mixture will be obtained.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=41, OH ^-/ SiO ₂=0.18, H ₂o/SiO ₂=28; Mixture is transferred in 1L stainless steel autoclave in 180 DEG C of standing crystallization 24h.After reaction terminates, product obtains through separation, washing, filtration, drying and other steps, and products therefrom is amorphous substance through XRD analysis, does not have the characteristic diffraction peak of ZSM-5 molecular sieve to occur.

Comparative example 4

The preparation of kaolin microsphere:

Spraying dry after 3012g kaolin, 1627g waterglass and 5358g distilled water mixing making beating is made the kaolin microsphere that particle diameter is 10 ~ 210um.By kaolin microsphere roasting 2h at 950 DEG C, obtain the kaolin microsphere after roasting, active SiO in this roasting kaolin microballoon ₂content is 46.1wt%, active A l ₂o ₃content 5.3wt%.Kaolin microsphere is analyzed through IR, at 550cm ^-1near there is not five-membered ring eigen vibration absworption peak.

In-situ crystallization ZSM-5-5 molecular sieve:

Take 30.0g roasting kaolin microballoon and 126g distilled water in beaker, beaker is put into 90 DEG C of water-baths, stir 5min; In beaker, add 88.0g waterglass, stir 20h; Then add 126g distilled water, after stirring 10min, in system, slowly add 26g 3M sulfuric acid solution regulation system basicity; Continue to stir 1h after adding sulfuric acid solution, uniform reactant mixture will be obtained.In reactant mixture, each component by the mol ratio of its oxide basis is: SiO ₂/ Al ₂o ₃=41, OH ^-/ SiO ₂=0.18, H ₂o/SiO ₂=28; Mixture is transferred in 1L stainless steel autoclave in 180 DEG C of standing crystallization 24h.After reaction terminates, product obtains through separation, washing, filtration, drying and other steps, and products therefrom is amorphous substance through XRD analysis, does not have the characteristic diffraction peak of ZSM-5 molecular sieve to occur.

The characterization result of the situ product synthesized by embodiment 1 ~ 9 and comparative example 1,2 and ex situ product is listed in table 1.

The character of table 1 crystallization product

Catalytic Cracking Performance is evaluated

By in-situ crystallization ZSM-5-5 microsphere zeolite catalyst of embodiment 4, comparative example 1 and comparative example 2 gained through 750 DEG C of 100% aging 16h of steam, as co-catalyst, major catalyst adopts LBO-16 (Petrochina Lanzhou Petrochemical Company).On small fixed flowing bed, with the charging of Petrochina Lanzhou Petrochemical Company 3,000,000 device, carry out catalytic cracking reaction evaluation, reaction condition and acquired results are in table 2.

As can be seen from Table 2, in-situ crystallization ZSM-5-5 molecular sieve of employing prepared by the embodiment of the present invention 4 is as FCC auxiliary agent compared with comparative example, and the productive rate of productivity of propylene and liquefied gas is higher.Light oil (gasoline+diesel oil) yield is suitable, and total liquid yield (liquefied gas+gasoline+diesel oil) improves.Therefore in-situ crystallization ZSM-5-5 molecular sieve that prepared by the present invention can be used in propylene enhancing in FCC process, increases economic efficiency.

The reactivity worth of table 2 catalyst

Claims (13)

1. a method for direct method in-situ crystallization synthesizing small crystal grain ZSM-5-5 molecular sieve, is characterized in that the method comprises:

(1). spraying dry after kaolin, waterglass, water mixing making beating is obtained kaolin microsphere, then obtains roasting kaolin microballoon through roasting, this roasting kaolin microballoon through infrared spectrum characterization, at 540 ~ 560cm ^-1there is in scope pentacyclic feature structure unit;

(2). the pretreatment of roasting kaolin microballoon: above-mentioned baked kaolin microsphere waterglass stirring reaction 6 ~ 60h at 40 ~ 120 DEG C is carried out pretreatment, wherein, OH in pretreatment mixed system ^-, H ₂the active SiO of O and roasting kaolin microballoon ₂amount calculate in molar ratio as OH ^-/ SiO ₂=0.3 ~ 3; H ₂o/SiO ₂=10 ~ 120; Wherein, OH ^-for the OH in waterglass ^-, SiO ₂for the active SiO in the kaolin microsphere after roasting ₂, H ₂o is water whole in system;

(3). the preparation of in-situ crystallization initial reactant: by sour regulation system basicity, adjust OH ^-/ SiO ₂to 0.12 ~ 0.20, make reactant mixture, wherein each component by the mol ratio of its oxide basis is:

SiO ₂/Al ₂O ₃＝25～80；

OH ^-/SiO ₂＝0.12～0.20；

H ₂O/SiO ₂＝10～80；

SiO in the mol ratio of above-mentioned reactant mixture ₂comprise the active SiO in the kaolin microsphere after roasting ₂with the SiO in waterglass ₂, Al ₂o ₃for the active A l in the kaolin microsphere after roasting ₂o ₃;

(4). carry out the in-situ crystallization of ZSM-5, after crystallization completes, then through washing, separation, filtration, dry obtained in-situ crystallization ZSM-5-5 molecular sieve and ex situ ZSM-5 molecular sieve.

2. method according to claim 1, is characterized in that in step (2): kaolin microsphere waterglass is stirring reaction 12 ~ 36h at 60 ~ 100 DEG C.

3. method according to claim 1, is characterized in that in step (2): OH in pretreatment mixed system ^-, H ₂the active SiO of O and roasting kaolin microballoon ₂amount calculate in molar ratio as OH ^-/ SiO ₂=0.6 ~ 2.6; H ₂o/SiO ₂=30 ~ 90.

4. method according to claim 1, is characterized in that in step (3): each component by the mol ratio of its oxide basis is:

SiO ₂/Al ₂O ₃＝35～65；

OH ^-/SiO ₂＝0.14～0.18；

H ₂O/SiO ₂＝20～50。

5. method according to claim 1, it is characterized in that in step (1): the kaolin microsphere sintering temperature that spraying dry is made is 500 ~ 1100 DEG C, roasting time is 0.1 ~ 10h.

6. method according to claim 1, it is characterized in that in step (1): kaolin microsphere is that the slurries spraying dry be mixed to get by kaolin, waterglass and water is prepared from, in butt quality, wherein: the amount of described waterglass is 1 ~ 10wt% of kaolin quality; The amount adding molecular sieve crystal seed in above-mentioned kaolin microsphere preparation process is SiO in kaolin ₂0 ~ 10wt% of quality; The amount adding expanding agent in kaolin microsphere preparation process is SiO in kaolin ₂0 ~ 10wt% of quality.

7. method according to claim 6, is characterized in that described molecular sieve crystal seed is one or more in ZSM-5 type, Y type and Beta type molecular sieve.

8. method according to claim 6, is characterized in that described molecular sieve crystal seed is type ZSM 5 molecular sieve.

9. method according to claim 6, is characterized in that described expanding agent is one or more in starch, oxidized starch, graft starch, acid treated starches, polyacrylamide.

10. the method according to claim 1 or 6, is characterized in that, with butt gauge in step (1), described kaolin amount is 75% ~ 96% of microballoon gross mass.

11. methods according to claim 1, is characterized in that acid used in step (3) is one or more in sulfuric acid, hydrochloric acid and nitric acid.

12. methods according to claim 1, it is characterized in that in the condition of step (4) situ crystallization be: crystallization temperature is 140 ~ 200 DEG C, and crystallization time is 6 ~ 48h.

13. methods according to claim 1 or 12, to is characterized in that in step (4) crystal pattern is for static, dynamically or batch (-type) dynamic crystallization.