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Abstrak :
[Preparasi zeolit berpori hierarki dari klinoptilolit Kalianda Lampung berhasil dilakukan dengan metode tandem acid-base treatments. Material zeolit alam berpori mikro dimodifikasi dengan menyatukan dua metode yang biasa dilakukan untuk mengubah ukuran mikropori zeolit menjadi mesopori, yaitu perlakuan asam (dealuminasi) dan perlakuan basa (desilikasi). Perlakuan asam diharapkan dapat meningkatkan rasio Si/Al sebagai hasil dari penurunan kadar Al, kemudian dilakukan perlakuan basa yang bertujuan untuk melarutkan sebagian atau menyeimbangkan kadar Si dan mengarahkan pembentukan mesopori dalam kerangka zeolit. Karakterisasi terhadap klinoptilolit raw dan hasil perlakuan asam-basa digunakan instrumen AAS, XRD, FTIR, dan BET surface area. Berdasarkan penelitian, Z-A4B1 memiliki sisi aktif yang cukup besar yang dapat berperan menjadi adsorben ion logam berat Cu(II) yang lebih baik karena kapasitas adsorpsi Z-A4B1 ini 4 kali lipat lebih tinggi daripada kapasitas adsorpsi dari klinoptilolit raw pada waktu optimum dan konsentrasi awal Cu(II) 300 ppm. Nilai KTK Z-A4B1 adalah sebesar 33,27 mg/g yang setara dengan 104,78 meq/100 g zeolit, sedangkan nilai KTK klinoptilolit raw adalah sebesar 72,19 meq/100 g zeolit. Adapun isoterm adsorpsi yang paling sesuai untuk menjelaskan mekanisme adsorpsi Cu(II) pada klinoptilolit berpori hierarki Z-A4B1 adalah model isoterm adsorpsi Freundlich. ;Hierarchical zeolites are prepared from Kalianda Lampung clinoptilolite by tandem acid-base treatments. Natural zeolites that are micropore intrinsicly was modified with two familiar methods that mostly used to change micropore size zeolite into hierarchical zeolite; acid treatment (dealumination) and base teratment (desilication). Acid treatments can increase Si/Al ratio of clinoptilolite because of Al content decreasing, then base treatment can balance Si content and aim the mesopore formation in zeolite frameworks. Intensive characterizations of both raw and modified clinoptilolites are conducted using XRD, AAS, FTIR, and BET surface area measurement. In this research, Z-A4B1 has more active sites to adsorb Cu(II) ions because the adsorption capacity of Z-A4B1 is up to 4-fold higher than the adsorption capacity of raw clinoptilolite at its optimum contact time and initial Cu(II) concentration 300 ppm. The CEC of Z-A4B1 is 33.27 mg/g that equals to 104.78 meq/100 g zeolite, besides CEC of raw clinoptilolite is 72.19 meq/100 g zeolite. Therefore, adsorption isoterm that fit to explain the adsorption Cu(II) mechanism at hierarichal zeolite Z-A4B1 is Freundlich isoterm adsorption model. , Hierarchical zeolites are prepared from Kalianda Lampung clinoptilolite by tandem acid-base treatments. Natural zeolites that are micropore intrinsicly was modified with two familiar methods that mostly used to change micropore size zeolite into hierarchical zeolite; acid treatment (dealumination) and base teratment (desilication). Acid treatments can increase Si/Al ratio of clinoptilolite because of Al content decreasing, then base treatment can balance Si content and aim the mesopore formation in zeolite frameworks. Intensive characterizations of both raw and modified clinoptilolites are conducted using XRD, AAS, FTIR, and BET surface area measurement. In this research, Z-A4B1 has more active sites to adsorb Cu(II) ions because the adsorption capacity of Z-A4B1 is up to 4-fold higher than the adsorption capacity of raw clinoptilolite at its optimum contact time and initial Cu(II) concentration 300 ppm. The CEC of Z-A4B1 is 33.27 mg/g that equals to 104.78 meq/100 g zeolite, besides CEC of raw clinoptilolite is 72.19 meq/100 g zeolite. Therefore, adsorption isoterm that fit to explain the adsorption Cu(II) mechanism at hierarichal zeolite Z-A4B1 is Freundlich isoterm adsorption model. ]

Abstrak :
[ABSTRAK
Telah dilakukan modifikasi zeolit alam dari Bayat-Klaten untuk material alternatif pengolahan limbah Thorium di Instalasi Pengolahan Limbah Radioaktif Batan. Zeolit alam yang umumnya merupakan material dengan ukuran mikropori dimodifikasi dengan menggabungkan dua metode yang biasa dilakukan untuk mengubah ukuran mikropori zeolit menjadi zeolit hierarki, yaitu dealuminasi dan desilikasi. Proses dealuminasi diharapkan dapat meningkatkan rasio Si:Al sehingga terjadi proses pengaturan ulang dalam kerangka zeolit, kemudian dilakukan proses desilikasi yang bertujuan untuk melarutkan sebagian Si dalam kerangka zeolit dan mengarahkan pembentukan mesopori dalam zeolit sehingga dapat meningkatkan kapasitas adsorpsi zeolit alam Bayat. Karakterisasi dilakukan dengan menggunakan XRD, FTIR, BET, SEM-EDS, dan AAS. Pola difraksi XRD untuk raw zeolite, zeolit pre-treatment, NaZ, ZA1, ZA2, ZA2B, ZB1 menunjukkan bahwa proses modifikasi ini tidak mengubah struktur kristal zeolit. Dalam penelitian ini setelah proses dealuminasi terjadi peningkatan rasio Si/Al dari sebelumnya 6,688 untuk NaZ menjadi 11,401 untuk zeolit alam termodifikasi dengan metode tandem acid-base treatments (ZA2B). Luas permukaan zeolit juga mengalami peningkatan, dari sebelumnya 125,4m2/g (NaZ) menjadi 216,8m2/g (ZA2B). Zeolit yang berhasil dimodifikasi memiliki sisi aktif yang cukup besar yang dapat berperan menjadi adsorben limbah Th4+ yang lebih baik daripada zeolit tanpa modifikasi. Terlihat dari data UV-Visibel larutan Th4+ yang teradsorpsi dalam zeolit alam termodifikasi adalah ca. 4,2 mg/g pada waktu 120 menit sementara pada waktu yang sama zeolit tanpa modifikasi hanya mengadsorpsi Th4+ sebesar ca. 3,92 mg/g. Adsorpsi Th(IV) oleh zeolit alam dari Bayat ini mengikuti isotherm adsorpsi Freundlich dengan kapasitas adsorpsi untuk NaZ dan ZA2B sebesar 909 mg/g dan 2000 mg/g. Hasil imobilisasi zeolit alam yang mengandung Th(IV) dengan menggunakan resin epoksi yang optimum didapat pada blok polimer-limbah dengan waste loading 30%.

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ABSTRACT
Hierarchical zeolite was prepared from natural zeolite using tandem acid-base treatments and applied as adsorbent in removal Th(IV) waste in the Installation of Radioactive Waste Management. Natural zeolite occurred naturally to have micropore size, was modified with two familiar methods that mostly used to change its micropore size into hierarchical pores in which are dealumination and desilication. Extensive characterization of both natural and modified zeolite were conducted using XRD, BET, SEM-EDS, AAS. XRD Pattern of Raw Zeolite, Pretreated Zeolite, NaZ, ZA1, ZA2, and ZA2B shows that the process to modify this material has not changed the crystallinity characteristic of this material. The Si/Al ratio is increased from 6.688 to 11.401 for NaZ and ZA2B respectively. Surface area is increased from 125.4 m2/g (NaZ) to216.8 m2/g (ZA2B). Application of these material as adsorbent were carried out using solution of 50 ppm Th4+. The UV-Vis result shows the modified zeolite (c.a. 10 mg) has higher adsorption capacity than the natural zeolite. The adsorption process is fit into Freundlich isotherm and the adsorption capacity of this material increase from 909 mg/g to 2000 mg/g for NaZ and ZA2B respectively.;Hierarchical zeolite was prepared from natural zeolite using tandem acid-base treatments and applied as adsorbent in removal Th(IV) waste in the Installation of Radioactive Waste Management. Natural zeolite occurred naturally to have micropore size, was modified with two familiar methods that mostly used to change its micropore size into hierarchical pores in which are dealumination and desilication. Extensive characterization of both natural and modified zeolite were conducted using XRD, BET, SEM-EDS, AAS. XRD Pattern of Raw Zeolite, Pretreated Zeolite, NaZ, ZA1, ZA2, and ZA2B shows that the process to modify this material has not changed the crystallinity characteristic of this material. The Si/Al ratio is increased from 6.688 to 11.401 for NaZ and ZA2B respectively. Surface area is increased from 125.4 m2/g (NaZ) to216.8 m2/g (ZA2B). Application of these material as adsorbent were carried out using solution of 50 ppm Th4+. The UV-Vis result shows the modified zeolite (c.a. 10 mg) has higher adsorption capacity than the natural zeolite. The adsorption process is fit into Freundlich isotherm and the adsorption capacity of this material increase from 909 mg/g to 2000 mg/g for NaZ and ZA2B respectively.;Hierarchical zeolite was prepared from natural zeolite using tandem acid-base treatments and applied as adsorbent in removal Th(IV) waste in the Installation of Radioactive Waste Management. Natural zeolite occurred naturally to have micropore size, was modified with two familiar methods that mostly used to change its micropore size into hierarchical pores in which are dealumination and desilication. Extensive characterization of both natural and modified zeolite were conducted using XRD, BET, SEM-EDS, AAS. XRD Pattern of Raw Zeolite, Pretreated Zeolite, NaZ, ZA1, ZA2, and ZA2B shows that the process to modify this material has not changed the crystallinity characteristic of this material. The Si/Al ratio is increased from 6.688 to 11.401 for NaZ and ZA2B respectively. Surface area is increased from 125.4 m2/g (NaZ) to216.8 m2/g (ZA2B). Application of these material as adsorbent were carried out using solution of 50 ppm Th4+. The UV-Vis result shows the modified zeolite (c.a. 10 mg) has higher adsorption capacity than the natural zeolite. The adsorption process is fit into Freundlich isotherm and the adsorption capacity of this material increase from 909 mg/g to 2000 mg/g for NaZ and ZA2B respectively., Hierarchical zeolite was prepared from natural zeolite using tandem acid-base treatments and applied as adsorbent in removal Th(IV) waste in the Installation of Radioactive Waste Management. Natural zeolite occurred naturally to have micropore size, was modified with two familiar methods that mostly used to change its micropore size into hierarchical pores in which are dealumination and desilication. Extensive characterization of both natural and modified zeolite were conducted using XRD, BET, SEM-EDS, AAS. XRD Pattern of Raw Zeolite, Pretreated Zeolite, NaZ, ZA1, ZA2, and ZA2B shows that the process to modify this material has not changed the crystallinity characteristic of this material. The Si/Al ratio is increased from 6.688 to 11.401 for NaZ and ZA2B respectively. Surface area is increased from 125.4 m2/g (NaZ) to216.8 m2/g (ZA2B). Application of these material as adsorbent were carried out using solution of 50 ppm Th4+. The UV-Vis result shows the modified zeolite (c.a. 10 mg) has higher adsorption capacity than the natural zeolite. The adsorption process is fit into Freundlich isotherm and the adsorption capacity of this material increase from 909 mg/g to 2000 mg/g for NaZ and ZA2B respectively.]