Electronic Theses and Dissertation

Selulosa asetat sebagai bahan dasar membran telah banyak diaplikasikan di berbagai bidang, hal ini dikarenakan kekuatan mekanik dan ketahanan termalnya yang tinggi. Untuk meningkatkan kinerja membran, selulosa asetat pada penelitian ini dikompositkan dengan pati dari umbi janeng (Dioscorea hispida D.) dan diikat silangkan (crosslinking) asam sitrat dengan beberapa variasi konsentrasi. Metode pembuatan membran pada penelitian ini metode inversi fasa. Hasil karakterisasi membran membran tanpa ikat silang (SA0) memiliki kuat tarik sebesar 1,56 kgf/mm2 sedangkan membran ikat silang asam sitrat 0,010 mol (SA2) memiliki kuat tarik yang baik yaitu 18,3 kgf/mm2. Membran SA0 memiliki derajat pengembangan dan porositas sebesar 39,15% dan 29,06%, sedangkan membran SA2 memiliki derajat pengembangan dan porositas yang lebih baik yaitu 43,08% dan 33,54%. Membran SA0 terdekomposisi pada suhu 367,37℃ dan mengalami penurunan berat sampel sebesar 97,333%, sedangkan membran SA2 terdekomposisi pada suhu 376,50℃ dan mengalami penurunan berat sampel sebesar 82,655%. Membran SA0 memiliki nilai fluks sebesar 81,01 L/m2 Jam, sedangkan membran SA2 memilki fluks sebesar 89,23 L/m2 Jam. Hasil pengujian kinetika dan isoterm adsorpsi menunjukkan adsorpsi urea menggunakan membran SA2 mengikuti kaidah kinetika Pseudo Second Order (PSO) dengan nilai R2 = 0,9975 dan kaidah isoterm Langmuir dengan nilai R2 = 0,9967. Membran SA0 dan SA2 mampu menurunkan konsentrasi urea masing-masing sebesar 27,70% dan 42,02%. Removal urea menggunakan membran ikat silang telah mendekati kadar normal urea yang ditetapkan.

Using of cellulose acetate as basic material for membranes had applied in various fields due to its high mechanical strength and thermal resistance. To upgrade the perfomance of membrane, cellulose acetate was composited with starch from (Dioscorea hispida D.) and crosslinked with citric acid in different concentrations. Method of membrane making in this reseacrh using phase inversion method. The results of characterization showed that the uncrosslinked membrane (SA0) had tensile strength of 1,56 kgf/mm2, while the crosslinked membrane with citric acid 0,010 mol (SA2) had better tensile strength of 18,3 kgf/mm2. Membrane SA0 had swelling degree of 39,15% and porosity of 29,06%, while membrane SA2 had better swelling degree of 43,08% and porosity of 33,54%. The temperature of decomposition for membrane SA0 was 367,37℃ and weight reduction sample was 97,333%, while the temperature of decomposition for membrane SA2 was 376,50℃ and weight reduction sample was 82,655%. The flux value for membrane SA0 was 81,01 L/m2h and for membrane SA2 was 89,23 L/m2h. The results of adsorption kinetics and isotherms test showed that urea adsorption using a membrane SA2 following the Pseudo Second Order (PSO) kinetic rule with a value of R2 = 0,9975 and the Langmuir adsorption isotherm rule with a value of R2 = 0,9967. Membrane SA0 can decrease urea was 27,20% and SA2 can decrease urea was 42,02%. Urea removal using crosslinked membrane has approched the normal urea levels that have been set.