Proceedings of The 5th Sriwijaya International Seminainar on Energy and Environmental Science & Technology Palembang, Indonesia September 10-11, 2014 Hydrothermal Synthesesis of Nanocrystalline Zeolite using Clelear Solution Syaifullah Muhammad1*, Izazarul Machdar1 , Sofyana1, Aris Munandar1, Tuty EEmilia Agustina3 Edy Saputaputra2 , Shaobin Wang4 and Moses O. Tade4 1 Chemical Engigineering Department Syiah Kuala University Banda Acehh 2 Chememical Engineering Department Riau University 3Chemicical Engineering Department Sriwijaya University 4 Chemical Engineeringng Department Curtin University of Technology Western AuAustralia *Correspsponding author: [email protected] ABSTRACT Nano size particles such as nanocrystatalline zeolites have unique properties relative to conventntional micrometer sized zeolite crystals. The reduction of particlicle size to the nanometer scale leads to substanti al changeses in properties of zeolite which make them as promising materiarials for many applications. Nanocrystalline zeolite A, siliclicate -1 and ZSM-5 were successfully synthesiszed at temperaturure of 80-1500C using clear solution in the presence of orgorganic templates. Values of 1.46, 3.06, 4.59 and 6.79 are effectivtive Si/Al ratio to synthesis LTA zeolite. Further, high Si/A/Al ratio of 30, 40 and 60 were used for ZSM-5 synthesis. The productp could be obtained at 1-5 day for zeolite A andd ZZSM-5 while silicate-1 (aluminum free) could be obtained att 5-9 day. It is proved that zeolite yields increased withh iincreasing temperature, time, Si/Al ratio and organic template.. MMoreover, TEOS and Ludox LS as silica sources in the ssilicate -1 synthesis were found to influence the particle size. TTEOS makes the zeolite particle smaller than Ludox LSLS. Two stage synthesis conducted on silicate-1 crystallizationn could decrease time and increase yield. However it is found that the average particle size was slightly higher than thattha in one-stage synthesis. Key words: Nanocrystalline zeolite, clealear solution, organic template, one-stage synthesis 1. INTRODUCTION (2003) who synthesized the mataterials at temperature of Nanozeolites are crystalline alumiinosilicates with 800C with initial Si/Al ratios of 3.05, 4.03, 5.03, 6.99 molecular dimension in the range of 100-1000 nm of the and 7.89 and particle sizes in ththe range of 50 -100 nm. particle size (Mintova, 2003). Nanoanozeoilites have The other researchers Persson eet al (19 94) reported the higher external surface area and reduceced diffusion path success of nanozeolite silicate-1 synthesis with average lengths due to smaller particle size. TheT reduction of particle size of less than 1000 nm at temperature of particle size to the nanometer scale leadads to substantial 1550C in 29 hours. Moreover,er, Grieken et al (2000) changes in properties of zeolite whichch make them as reported the synthesis of nananocrystalline ZSM-5 at promising materials for many applicatiotions. 1700C for 24 hours with 10-100 nm particle sizes. The Zeolite nanocrystals are usually synthesizedsy under initial SiO2/Al2O3 of molar ratiotio used in the synthesis hyhrothermal condition using clearr aluminosilicate process is 60. With the similarr pprocedure to Grieken et solution, usually in the presence of orgarganic compounds al, Song et al (2004) synthesizedzed nanocrystalline ZSM - as templates such as tetramethylammononium (TMA) and 5 at temperature of 1650C withith Si/Al ratio of 20. The tetrapropylammonium (TPA) (Zhan,n, et al. 2001). obtained ZSM-5 particles weree 115 -60 nm for 120 hours Further, Cundy and Cox (202004) reported synthesis time. aluminosilicate zeolites synthehesized under hydrothermal condition from reactivee gels in alkaline media at temperature of about 800C and 2000C and most high Si/Al ratio of zeolites (>10)0) are synthesized using organic templates, which havee to be removed from the zeolites structure by calcinainations. Mintova (2003) reported the synthesis of nanano size zeolites including nanozeolite A (LTA), nanozezeolite Y (FAU), nanozeolite silicate-1 (MFI) and nanozeolitena beta (BEA) at temperatures lower than 1000C with synthesis time up to 400 hours. The successfsful synthesis of Figure 1. Zeolite framemework and channel dimension (pore opening),, (A) LTA, (B) MFI nanozeolite A was also reported by RakoczyRa and Traa 80 Proceedings of The 5th Sriwijaya International Seminar on Energy and Environmental Science & Technology Palembang, Indonesia September 10-11, 2014 (http://www.iza-stucture.org, retrieved: 10 August centrifugation for 4 times were done to purify the 2007) product and finally filtration was employed to obtain the nanozeolite A product. next, the product was dried Many other researchers reported the success of at 120 0C for 24 hours and then calcined at temperature nanozeolite synthesis which indicate the interesting and of 550 0C for 3 hours. promising prospect of nanozeolite technology (Tosheva & Valtchev, 2005). Figure 1 shows the description of 2.2 Synthesis of nanozeolite silicate-1 (MFI) zeolite framework and channel dimension of LTA, Synthesis solution was made by adding FAU and MFI. tetrapropylammonium hydroxide (TPAOH, Sigma This article reports experimental studies on Aldrich) into silica sources (Ludox LS or TEOS) and synthesis of nanocrystalline zeolite A, silicate-1 and followed by strong mixing. The solution was then ZSM-5 under hydrothermal condition using clear added by distilled water and ethanol. If the silica solution in the present of organic template. Some source is TEOS (tetraethyl orthosilicate), the synthesis parameters in synthesis process such as the effects of solution was shaken for 12 hours on a shaker time, temperature, initial Si/Al ratio, and specific (Certomat R Shaker from B. Braun). The synthesis reactant will be evaluated. mixtures with molar composition 2TPAOH: 0.15Na2O: 6SiO2: 532H2O: 51EtOH (Ludox LS as 2. METHODS silica source) and 2TPAOH: 0.15Na2O: 4.5Si: 2.1 Synthesis of nanozeolite A (LTA) 382H2O: 51EtOH (TEOS as silica source) were In preparation of LTA, two typical solutions have obtained. In the next step, the synthesis mixture was been deployed, namely solution-1 and solution-2. The transferred to the crystallization vessel and heated in an solution-1 is composed of aluminum tri-isopropoxide oven at temperatures of 800C, 1200C and 1500C. After (Al(OiPr)3, 99.99%, Sigma-Aldrich) dispersed in a certain synthesis time, the product was separated distillated water and sodium hydroxide (NaOH, 1M). from mother liquor by centrifuge (Heraeus Multifuge Furthermore, the solution was vigorously stirred for an 1s Kendro) at 4700 rpm for 2 hours. The solid phase hour. After that, TMAOH (25 wt.% in water, Sigma- was then rinsed up to 5 times and filtered. After that, Aldrich) was added. The solution-2 is composed of the product was dried at 120 0C for 24 hours and then Ludox LS colloidal silica (30 wt.%, Sigma-Aldrich) calcined at temperature of 6000C for 3 hours. The and distilled water. Next, the solution-1 and solution-2 temperatures of 800C and 1200C were used for two were mixed under constant stirring to produce a clear stages synthesis period with varying of temperatures synthesis solution. The molar composition of various where 3, 4 and 5 days synthesis time were used at 800C synthesis solutions are shown in Table. 1. as the first stage and another 1 day was used at 1200C as the second stage. Table 1. Molar composition of zeolite A synthesis solution 2.3 Synthesis of nanozeolite ZSM-5 (MFI) SAMPLE Si/Al MOLAR COMPOSITION ZSM-5 synthesis was started by adding aluminum 2.92SiO2: Al2O3: 0.29Na2O: LTA-1 1.46 isopropoxide (Al(OiPr)3) into the mixture of distilled 0.58(TMA)2O: 493.57H2O LTA-4, LTA-5, water and tetrapropylammonium hydroxide (TPAOH). 6.12SiO : Al O : 0.29Na O: LTA-6, LTA-19, 3.06 2 2 3 2 After a clear solution was obtained with stirring at 2.24 (TMA) O: 345.36H O LTA-20, LTA-21 2 2 room temperature, ethanol was then added into the LTA-8, LTA-9, solution followed by adding sodium hydroxide. And LTA-10, LTA- 9.18SiO : Al O : 0.29Na O: then, TEOS as silica source was added and stirred for 11, LTA-23, 4.59 2 2 3 2 2.8 (TMA) O: 458.9H O LTA-24, LTA- 2 2 24 hours to ensure complete hydrolysis of TEOS. The 25, LTA-26 molar composition of synthesis solution is depicted in 13.58SiO : Al O : LTA-14, LTA- 2 2 3 Table 2. 6.79 0.23Na2O: 4.48(TMA)2O: 15, LTA-16 538.59H2O LTA-28, LTA- Table 2. Molar composition of ZSM-5 synthesis 6.12SiO : Al O : 0.25Na O: 29, LTA-30, 3.06 2 2 3 2 solution 2.24(TMA) O: 359.73H O LTA-31 2 2 SAMPLE Si/Al MOLAR COMPOSITION LTA-33, LTA- ZSM5-1, 1.48TPAOH: 0.33Na O: 0.49Al: 9.18SiO : Al O : 0.31Na O: 30 2 34, LTA-35, 4.59 2 2 3 2 ZSM5-2 14.4Si: 656.83H O: 97.68EtOH 2.80 (TMA) O: 461.58H O 2 LTA-36 2 2 ZSM5-3, 1.48TPAOH: 0.33Na O: 0.24Al: 40 2 ZSM5-4 9.6Si: 656.83H2O: 97.68EtOH ZSM5-5, 1.48TPAOH: 0.33Na O: 0.24Al: Then, the solution was put in a stainless steel 60 2 ZSM5-6 14.4Si: 656.83H O: 97.68EtOH autoclave (100 ml) for crystallisation at temperature of 2 800C, 1200C and 150 0C in an oven. The autoclave was Finally the synthesis solution was transferred into subjected to varying crystallisation time, from 1 day to the bottle and put into an oven for crystallization at 5 days. The product was then separated from solution 900C. After a certain time, the samples were taken and in a centrifuge with 4700 rpm for 3 hours (Heraeus separated by using the centrifuge at 4700 rpm for 2 Multifuge 1s Kendro).