[ABSTRAK Telah dilakukan modifikasi zeolit alam dari Bayat-Klaten untuk material alternatifpengolahan limbah Thorium di Instalasi Pengolahan Limbah Radioaktif Batan.Zeolit alam yang umumnya merupakan material dengan ukuran mikroporidimodifikasi dengan menggabungkan dua metode yang biasa dilakukan untukmengubah ukuran mikropori zeolit menjadi zeolit hierarki, yaitu dealuminasi dandesilikasi. Proses dealuminasi diharapkan dapat meningkatkan rasio Si:Alsehingga terjadi proses pengaturan ulang dalam kerangka zeolit, kemudiandilakukan proses desilikasi yang bertujuan untuk melarutkan sebagian Si dalamkerangka zeolit dan mengarahkan pembentukan mesopori dalam zeolit sehinggadapat meningkatkan kapasitas adsorpsi zeolit alam Bayat. Karakterisasi dilakukandengan menggunakan XRD, FTIR, BET, SEM-EDS, dan AAS. Pola difraksi XRDuntuk raw zeolite, zeolit pre-treatment, NaZ, ZA1, ZA2, ZA2B, ZB1menunjukkan bahwa proses modifikasi ini tidak mengubah struktur kristal zeolit.Dalam penelitian ini setelah proses dealuminasi terjadi peningkatan rasio Si/Aldari sebelumnya 6,688 untuk NaZ menjadi 11,401 untuk zeolit alam termodifikasidengan metode tandem acid-base treatments (ZA2B). Luas permukaan zeolit jugamengalami peningkatan, dari sebelumnya 125,4m2/g (NaZ) menjadi 216,8m2/g(ZA2B). Zeolit yang berhasil dimodifikasi memiliki sisi aktif yang cukup besaryang dapat berperan menjadi adsorben limbah Th4+ yang lebih baik daripadazeolit tanpa modifikasi. Terlihat dari data UV-Visibel larutan Th4+ yangteradsorpsi dalam zeolit alam termodifikasi adalah ca. 4,2 mg/g pada waktu 120menit sementara pada waktu yang sama zeolit tanpa modifikasi hanyamengadsorpsi Th4+ sebesar ca. 3,92 mg/g. Adsorpsi Th(IV) oleh zeolit alam dariBayat ini mengikuti isotherm adsorpsi Freundlich dengan kapasitas adsorpsi untukNaZ dan ZA2B sebesar 909 mg/g dan 2000 mg/g. Hasil imobilisasi zeolit alamyang mengandung Th(IV) dengan menggunakan resin epoksi yang optimumdidapat pada blok polimer-limbah dengan waste loading 30%. ABSTRACT Hierarchical zeolite was prepared from natural zeolite using tandem acid-basetreatments and applied as adsorbent in removal Th(IV) waste in the Installation ofRadioactive Waste Management. Natural zeolite occurred naturally to havemicropore size, was modified with two familiar methods that mostly used tochange its micropore size into hierarchical pores in which are dealumination anddesilication. Extensive characterization of both natural and modified zeolite wereconducted using XRD, BET, SEM-EDS, AAS. XRD Pattern of Raw Zeolite, PretreatedZeolite, NaZ, ZA1, ZA2, and ZA2B shows that the process to modify thismaterial has not changed the crystallinity characteristic of this material. The Si/Alratio is increased from 6.688 to 11.401 for NaZ and ZA2B respectively. Surfacearea is increased from 125.4 m2/g (NaZ) to216.8 m2/g (ZA2B). Application ofthese material as adsorbent were carried out using solution of 50 ppm Th4+. TheUV-Vis result shows the modified zeolite (c.a. 10 mg) has higher adsorptioncapacity than the natural zeolite. The adsorption process is fit into Freundlichisotherm and the adsorption capacity of this material increase from 909 mg/g to2000 mg/g for NaZ and ZA2B respectively.;Hierarchical zeolite was prepared from natural zeolite using tandem acid-basetreatments and applied as adsorbent in removal Th(IV) waste in the Installation ofRadioactive Waste Management. Natural zeolite occurred naturally to havemicropore size, was modified with two familiar methods that mostly used tochange its micropore size into hierarchical pores in which are dealumination anddesilication. Extensive characterization of both natural and modified zeolite wereconducted using XRD, BET, SEM-EDS, AAS. XRD Pattern of Raw Zeolite, PretreatedZeolite, NaZ, ZA1, ZA2, and ZA2B shows that the process to modify thismaterial has not changed the crystallinity characteristic of this material. The Si/Alratio is increased from 6.688 to 11.401 for NaZ and ZA2B respectively. Surfacearea is increased from 125.4 m2/g (NaZ) to216.8 m2/g (ZA2B). Application ofthese material as adsorbent were carried out using solution of 50 ppm Th4+. TheUV-Vis result shows the modified zeolite (c.a. 10 mg) has higher adsorptioncapacity than the natural zeolite. The adsorption process is fit into Freundlichisotherm and the adsorption capacity of this material increase from 909 mg/g to2000 mg/g for NaZ and ZA2B respectively.;Hierarchical zeolite was prepared from natural zeolite using tandem acid-basetreatments and applied as adsorbent in removal Th(IV) waste in the Installation ofRadioactive Waste Management. Natural zeolite occurred naturally to havemicropore size, was modified with two familiar methods that mostly used tochange its micropore size into hierarchical pores in which are dealumination anddesilication. Extensive characterization of both natural and modified zeolite wereconducted using XRD, BET, SEM-EDS, AAS. XRD Pattern of Raw Zeolite, PretreatedZeolite, NaZ, ZA1, ZA2, and ZA2B shows that the process to modify thismaterial has not changed the crystallinity characteristic of this material. The Si/Alratio is increased from 6.688 to 11.401 for NaZ and ZA2B respectively. Surfacearea is increased from 125.4 m2/g (NaZ) to216.8 m2/g (ZA2B). Application ofthese material as adsorbent were carried out using solution of 50 ppm Th4+. TheUV-Vis result shows the modified zeolite (c.a. 10 mg) has higher adsorptioncapacity than the natural zeolite. The adsorption process is fit into Freundlichisotherm and the adsorption capacity of this material increase from 909 mg/g to2000 mg/g for NaZ and ZA2B respectively., Hierarchical zeolite was prepared from natural zeolite using tandem acid-basetreatments and applied as adsorbent in removal Th(IV) waste in the Installation ofRadioactive Waste Management. Natural zeolite occurred naturally to havemicropore size, was modified with two familiar methods that mostly used tochange its micropore size into hierarchical pores in which are dealumination anddesilication. Extensive characterization of both natural and modified zeolite wereconducted using XRD, BET, SEM-EDS, AAS. XRD Pattern of Raw Zeolite, PretreatedZeolite, NaZ, ZA1, ZA2, and ZA2B shows that the process to modify thismaterial has not changed the crystallinity characteristic of this material. The Si/Alratio is increased from 6.688 to 11.401 for NaZ and ZA2B respectively. Surfacearea is increased from 125.4 m2/g (NaZ) to216.8 m2/g (ZA2B). Application ofthese material as adsorbent were carried out using solution of 50 ppm Th4+. TheUV-Vis result shows the modified zeolite (c.a. 10 mg) has higher adsorptioncapacity than the natural zeolite. The adsorption process is fit into Freundlichisotherm and the adsorption capacity of this material increase from 909 mg/g to2000 mg/g for NaZ and ZA2B respectively.] |