HRP920578A2

HRP920578A2 - PROCESS FOR THE PRODUCTION OF ZEOLITE NaA

Info

Publication number: HRP920578A2
Application number: HR920578A
Authority: HR
Inventors: Jurgen Dorr
Original assignee: Degussa
Priority date: 1988-06-30
Filing date: 1992-09-29
Publication date: 1994-10-31

Description

Područje tehnike The field of technology

Izum je iz područja proizvodnje sredstava za pranje i odnosi se na postupak za proizvodnju zeolita NaA, koji služi za zamjenu fosfata u sredstvima za pranje. The invention is from the field of production of detergents and relates to the process for the production of zeolite NaA, which serves to replace phosphate in detergents.

Tehnički problem Technical problem

Tehnički problem koji se rješava ovim izumom je ubrzavanje kristalizacije u postupku proizvodnje zeolita NaA tako da završna faza kristalizacije više ne bude potrebna, a da pri tome kristalni zeolit ima istu razdiobu veličine čestica kao kristalni inokulat. The technical problem solved by this invention is the acceleration of crystallization in the production process of zeolite NaA so that the final crystallization phase is no longer necessary, and the crystalline zeolite has the same particle size distribution as the crystalline inoculum.

Stanje tehnike State of the art

Poznat je postupak proizvodnje kristalnog zeolitnog praha tipa A, čiji sastav je: 1,0 ± 0,2 Na2O : A12O3 : 1,85 ±0,5 SiO2-yH2O, pri čemu y je jedna vrijednost do 6, s 50 mas. % čestica ispod 4,0 μm i spektrom čestica The process of producing crystalline zeolite powder type A is known, the composition of which is: 1.0 ± 0.2 Na2O : A12O3 : 1.85 ±0.5 SiO2-yH2O, where y is a value up to 6, with 50 wt. % of particles below 4.0 μm and by the particle spectrum

[image] [image]

U ovom postupku polazi se od vodene otopine natrij silikata, koji se grije na temperaturu od 30 do 80°C. Uz miješanje dodaje se prethodno zagrijana na 30 do 100°C baza natrij aluminata, koja sadrži 0,1 do 100 g Al2O3/l i 1 do 200 g Na2O/l u postojeću otopinu natrij silikata do zamućenja reakcijske smjese u roku od 10 do 60 minuta. U ovu zamućenu reakcijsku smjesu, koja sadrži SiO2/Al2O3 = 2 do 50, Na2O/SiO2 = 0,2 do 20 i H2O/Na2O = 4 do 300, dodaje se otopina natrij aluminata koja sadrži 10 do 200 g/l A12O3 i 10 do 250 g/l Na2O, pri temperaturi od 10 do 100°C. Miješajući dodavanje se provodi u dva dijela, pri čemu je brzina drugog dodavanja 2 do 10 puta veća od prvog. Tako dobivena sintetička smjesa pri temperaturi između 20 i 175°C kristalizira u roku od najmanje 15 minuta (DE-PS 26 60 723). In this process, the starting point is an aqueous solution of sodium silicate, which is heated to a temperature of 30 to 80°C. With stirring, preheated to 30 to 100°C sodium aluminate base, containing 0.1 to 100 g Al2O3/l and 1 to 200 g Na2O/l, is added to the existing sodium silicate solution until the reaction mixture becomes cloudy within 10 to 60 minutes. A sodium aluminate solution containing 10 to 200 g/l A12O3 and 10 up to 250 g/l Na2O, at a temperature of 10 to 100°C. Mixing addition is carried out in two parts, where the speed of the second addition is 2 to 10 times higher than the first. The thus obtained synthetic mixture crystallizes at a temperature between 20 and 175°C within at least 15 minutes (DE-PS 26 60 723).

Po ovoj metodi nakon faze zagrijavanja dolazi do optimalnog kristaliziranja, te zahtjeva priključenje na dužu kristalizacijsku fazu. According to this method, optimal crystallization occurs after the heating phase, and requires connection to a longer crystallization phase.

Proizvod dobiven po ovoj poznatoj metodi koristi se kao supstituent fosfata odnosno kao zamjena fosfata u sredstvima za pranje. Stoga je za proizvodnju neophodno osigurati što veću vezivnu sposobnost kalcija i definiranu razdiobu veličine čestica. The product obtained by this well-known method is used as a phosphate substitute, i.e. as a replacement for phosphate in detergents. Therefore, for production, it is necessary to ensure the greatest binding capacity of calcium and a defined particle size distribution.

Da bi se omogućila nesmetana i ponovljiva razdioba veličina čestica zeolita A, kod ove metode odustalo se od primjene modifikatora. Primjena modifikatora pri sintezi zeolita opće je poznata. In order to enable a smooth and reproducible distribution of zeolite A particles, the use of modifiers was abandoned in this method. The use of modifiers in the synthesis of zeolites is generally known.

Tako je u DE-OS 35 38 416 proizvodnja fojazita opisana s primjenom amorfnog modifikatora. Thus, in DE-OS 35 38 416, the production of foyasite is described with the application of an amorphous modifier.

Prema US-PS 33 10 373 se upravo dobiveni kristali melju u kugličnom mlinu, pri čemu vjerojatno nastaju centri modifikatora. O razdiobi veličina čestica u tom tekstu nije ništa rečeno. According to US-PS 33 10 373, the crystals just obtained are ground in a ball mill, where modifier centers are probably formed. Nothing was said about the distribution of particle sizes in that text.

Iz US-PS 30 71 434 poznato je da se kristalni zeolit tipa NaA modificira recikliranjem dobivenog kristalnog proizvoda. O rasporedu veličine čestica ovog proizvoda u US-PS 30 71 434 nije ništa priopćeno. From US-PS 30 71 434 it is known that crystalline zeolite of type NaA is modified by recycling the resulting crystalline product. Nothing is disclosed about the particle size distribution of this product in US-PS 30 71 434.

Opis rješenja tehničkog problema s primjerima izvođenja Description of the solution to the technical problem with implementation examples

Navedeni tehnički problem rješava se postupkom prema izumu, koji se od poznatih postupaka te vrste razlikuje time što se kristalni prah zeolita NaA, koji sadrži 1,0 ± 0,2 Na2O : A12O3 : 1, 85 ± 0,5 SiO2-yH2O, pri čemu vrijednost y treba uzeti do 6, s masenim % čestica ispod 0,4 μm i razdiobom čestica The mentioned technical problem is solved by the process according to the invention, which differs from known processes of this type in that the crystalline powder of zeolite NaA, which contains 1.0 ± 0.2 Na2O : A12O3 : 1.85 ± 0.5 SiO2-yH2O, at why the value of y should be taken up to 6, with mass % of particles below 0.4 μm and particle distribution

[image] [image]

dodaje reakcijskoj smjesi kao centar jezgre kristala. adds to the reaction mixture as the center of the crystal nucleus.

Zeolit NaA u prahu proizvodi se poznatim postupkom prema DE-PS 26 60 723. To se odvija tako da se uzima vodenu otopinu natrij silikata zagrijanu do temperature između 30 i 80°C. Miješajući dogrijava se do temperature od 30 do 100°C i dodaje otopina natrij aluminata sa sadržajem od 0,1 do 100 g A12O3/l i 1 do 200 g Na2O/l u postojeću otopinu natrij silikata do točke zamućenja reakcijske smjese u roku od 10 do 60 minuta. U ovu zamućenu reakcijsku smjesu, koja sadrži SiO2/ A12O3 = 2 do 50, Na2O/ SiO2 = 0,2 do 20 i H20/ Na2O = 4 do 300, dodaje se otopina natrij aluminata koja sadrži 10 do 200 g/l A12O3 i 10 do 250 g/l Na2O, pri temperaturi od 10 do 100°C. Uz miješanje dodavanje se provodi dvokratno, pri čemu je brzina drugog dodavanja 2 do 10 puta veća od prvog. Tako dobivena sintetička smjesa pri temperaturi između 20 i 175°C kristalizira u roku od najmanje 15 minuta. Zeolite NaA in powder is produced by a known process according to DE-PS 26 60 723. This takes place by taking an aqueous solution of sodium silicate heated to a temperature between 30 and 80°C. With stirring, it is heated to a temperature of 30 to 100°C and a sodium aluminate solution with a content of 0.1 to 100 g A12O3/l and 1 to 200 g Na2O/l is added to the existing sodium silicate solution to the point of turbidity of the reaction mixture within 10 to 60 minute. A sodium aluminate solution containing 10 to 200 g/l A12O3 and 10 up to 250 g/l Na2O, at a temperature of 10 to 100°C. With mixing, the addition is carried out twice, whereby the speed of the second addition is 2 to 10 times higher than the first. The thus obtained synthetic mixture crystallizes at a temperature between 20 and 175°C within at least 15 minutes.

Pri najsvrhovitijem ostvarenju izuma, kao kristalni inokulat upotrijebljen je kristal zeolita tipa NaA postupkom prema DE-PS 26 60 723. Dodavanje kristala za inokulaciju može se izvršiti u bilo kojem trenutku reakcije, prvenstveno prije završetka dodavanja aluminata. In the most practical embodiment of the invention, a NaA-type zeolite crystal was used as the crystal inoculum according to DE-PS 26 60 723. The addition of crystals for inoculation can be performed at any time of the reaction, primarily before the end of adding aluminate.

Dodavanje kristala za modificiranje vrši se i po poznatim postupcima, a također i po ispitativanoj metodi, da se poboljša učinak skraćenja vremena kristalizacije. The addition of crystals for modification is done according to known procedures, and also according to the tested method, to improve the effect of shortening the crystallization time.

Neočekivano, postupkom prema izumu nastaje kristalni zeolit, koji pokazuje istu razdiobu veličine čestica kao i kristali za inokulaciju i bez ogorina je. Unexpectedly, the process according to the invention results in a crystalline zeolite, which exhibits the same particle size distribution as the inoculation crystals and is free of scale.

Ako se pode od teorije rasta kristala, treba uzeti u obzir da kristali moraju biti manji nego željeni proizvod, jer se kristalizacija odvija prvenstveno na postojećim mjestima centara kristalizacije. If we start from the theory of crystal growth, it should be taken into account that the crystals must be smaller than the desired product, because crystallization takes place primarily in the existing places of crystallization centers.

Posebna prednost novoizumljenog postupka je to da se upravo po završetku faze zagrijavanja proizvoda pokazuju željene značajke kao što je vezivna sposobnost kalcija, nepostojanje ogorina i razdioba veličine žestica. A special advantage of the newly invented process is that it is precisely after the heating phase of the product that the desired features such as calcium binding capacity, absence of scale and particle size distribution are shown.

Završna faza kristalizacije više nije potrebna. The final crystallization stage is no longer necessary.

Primjeri Examples

U posudu volumena 150 ml stavljeno je tekuće staklo. Liquid glass was placed in a container with a volume of 150 ml.

Miješajući tekućem staklu zagrijanom na 50°C tijekom 30 minuta dodaje se otopina aluminata I temperature 80°C. Prije kraja dodavanja dolazi do zamućenja smjese. A solution of aluminate I at a temperature of 80°C is added to the liquid glass heated to 50°C for 30 minutes while stirring. Before the end of the addition, the mixture becomes cloudy.

U slabo zamućenu otopinu tijekom narednih 45 minuta dodaje se 20 l, a potom tijekom narednih 30 minuta ostatak otopine aluminata II (temperatura otopine aluminata II: 70°C). 20 l is added to the slightly cloudy solution over the next 45 minutes, and then over the next 30 minutes the rest of the aluminate II solution (temperature of the aluminate II solution: 70°C).

Reakcijska smjesa zagrije se na 87°C. Nakon toga čvrsti sadržaj se filtrira, ispire, suši i analizira. The reaction mixture is heated to 87°C. After that, the solid content is filtered, washed, dried and analyzed.

Koncentracija upotrijebljene otopine i sastav smjese koja se taloži prikazani su u tablici 1. The concentration of the solution used and the composition of the precipitated mixture are shown in Table 1.

Podaci analiza dati su u tablici 2. Određivanje veličine čestica vrši se Coulter-Counter-mjerenjem. Analysis data are given in table 2. Determination of particle size is done by Coulter-Counter-measurement.

Određivanje faze kristalizacije vrši se rentgenografski. Determination of the phase of crystallization is carried out X-ray.

Primjer 1 ne sadrži kristale za inokulaciju. Primjeri 2 do 4 sadrže 2 do 3% kristala za inokulaciju proizvedenih prema DE-PS 2 6 60 723. Example 1 does not contain crystals for inoculation. Examples 2 to 4 contain 2 to 3% of inoculation crystals produced according to DE-PS 2 6 60 723.

Tablica 1 Table 1

[image] [image]

+)Odnosi se na zeolit A, atro. +)Refers to zeolite A, atro.

Dodaju se slijedeće otopine: The following solutions are added:

Tekuće staklo: Liquid glass:

N2O : 107 g/l N2O: 107 g/l

= 1,35 g/cm3 = 1.35 g/cm3

SiO2 : 347,5 g/l SiO2: 347.5 g/l

Otopina natrij aluminata: Sodium aluminate solution:

N2O : 94, 8 - 103, 8 g/l N2O: 94.8 - 103.8 g/l

= 1,10 g/cm3 = 1.10 g/cm3

A12O3 : 6,4 - 9, 6 g/l A12O3: 6.4 - 9.6 g/l

Otopina natrij aluminata: Sodium aluminate solution:

N2O : 160,3 - 182, 8 g/l N2O: 160.3 - 182.8 g/l

= 1,37 g/cm3 = 1.37 g/cm3

A12O3 : 93, 8 - 99,4 g/l A12O3: 93.8 - 99.4 g/l

[image] [image]

Claims

1. Process for the production of zeolite NaA, indicated by the fact that the crystalline powder of zeolite NaA, composition 1.0 ± 0.2 Na2O : Al2O3 : 1.85 ± 0.5 SiO2·yH2O, where the value of y should be taken up to 6, with 50 mass % of particles below 4.0 µm and particle distribution [image] adds to the reaction mixture as the center of the crystal nucleus.