Judul: Effect of EFB Elements on Pulp and Viscose as Raw Materials for Viscose Rayon Staples
Abstrak: Serat viskosa merupakan serat semi sintetis yang berasal dari proses regenerasi selulosa dengan dissolving pulp sebagai bahan baku. TKKS memiliki kandungan selulosa yang cukup tinggi sehingga dalam penelitian ini akan diolah sebagai dissolving pulp. Tujuan penelitian ini adalah mengetahui bagian TKKS terbaik yang dapat menghasilkan pulp dan viscose sesuai dengan standar. Penelitian ini juga bertujuan mengetahui waktu terbaik dalam proses aging dan konsentrasi CS2 yang dapat menghasilkan viscose. Proses pembuatan pulp menggunakan metode prahidrolisis kraft karena memiliki kelebihan dapat menghasilkan pulp dengan kemurnian tinggi. Dissolving pulp yang didapatkan selanjutnya diolah menjadi bahan baku pembuatan larutan viscose. Viscose merupakan larutan yang berasal dari pulp hasil aging kemudian diberikan CS2 membentuk selulosa xantat yang selanjutnya dilarutkan. Pengujian yang dilakukan berupa pengujian kimia bahan baku dan dissolving pulp, pengujian XRD, SEM-EDX, dan pengujian FTIR. Pada proses aging dilakukan variasi waktu dan pada proses xantasi konsentrasi CS2 divariasikan. Hasil penelitian menunjukkan TKKS stalk menghasilkan pulp terbaik yang sesuai dengan standar SNI. Pembuatan viscose dari kedua sampel menunjukkan bahwa pulp TKKS stalk menghasilkan viscose sesuai dengan standarisasi., In the cellulose regeneration process, the basic material for viscose fiber is dissolving pulp. OPEFB will be used as dissolving pulp because of its high cellulose content. This research aims to discover industry-standard OPEFB components for pulp and viscose production. Viscosity can also be produced by determining the ideal time of aging and the concentration of CS2 that produces it. The kraft prehydrolysis method is used in the pulp producing process because it produces high-purity pulp. Raw materials for viscose solution are made from the dissolving pulp. To make cellulose xanthate, aged pulp is mixed with CS2 to generate viscose, which is then dissolved in water. Raw materials and dissolving pulp are subjected to chemical testing, as well as XRD, SEM-EDX, and FTIR testing. In the viscose process, aging time and CS2 concentration are varied. In compliance with SNI criteria, OPEFB stalk pulp was found to provide the best pulp. Both samples showed OPEFB stalk pulp met viscose production standards.
Keyword: Cellulose, Dissolving Pulp, OPEFB, Viscose

Judul: Modification of the Surface Properties of Oil Palm Empty Leaves (EFB) using the Delignification Method
Abstrak: Delignifikasi merupakan tahap awal yang bertujuan untuk mengurangi komposisi kimia non-selulosa di dalam serat TKKS. Delignifikasi dapat memutuskan ikatan non-selulosa dan melarutkan impuritas agar selulosa menjadi lebih mudah diurai. Tujuan penelitian ini dilaksanakan untuk memperoleh serat panjang TKKS dengan metode delignifikasi dan mengaplikasikannya dalam kain nonwoven serta mendapatkan kajian sifat mekanik. Proses pembuatan serat menggunakan pra-perlakuan sodium klorit-asam asetat (SC-AA) dan alkaline peroxide (AP), kemudian dilakukan pengujian komponen kimia menggunakan TAPPI. Hasil pengujian Sampel dikarakterisasi menggunakan alat TGA, FTIR, ASTM D 5035 dan ASTM D 5587. Hasil penelitian menunjukkan bahwa, berdasarkan uji termal (TGA) Sampel A6 memiliki kemampuan termal lebih baik dengan degradasi massa yang kecil 29% karena perlakuan AP mampu degradasi impuritas dan komposisi non-selulosa lebih tinggi dibandingkan perlakuan SC-AA. Sedangkan pada uji FTIR gugus fungsi pada bilangan gelombang 1030 cm-1 (C-O), 2300 cm-1 (O-H), 2900 cm-1 (C-H) menunjukkan terjadi penurunan persen transmitansi pada sampel A4 dan A6 dibandingkan kontrol. Hasil uji tarik dan sobek serat TKKS yang terbaik berdasarkan perlakuan alkaline peroxide yaitu pada nonwoven 4 lapis, semakin besar lapisannya maka kekuatan sobek dan tarik semakin tinggi. Delignifikasi terbaik adalah sampel alkaline peroxide (180 menit) dan berdasarkan uji mekanik serat TKKS nonwoven lapisan 4 dengan gramassi 1700 g/m2., Delignification is an initial step that aims to reduce the chemical composition of non-cellulose in the OPEFB fibers. Delignification can break non- cellulose bonds and dissolve impurities to make cellulose easier to break down. The purpose of this study was to obtain long fiber OPEFB by delignification method and apply it to non-woven fabrics and obtain a study of its mechanical properties. The fiber manufacturing process uses pre-treatment of sodium chlorite-acetic acid (SC-AA) and alkaline peroxide (AP), then testing the chemical components using TAPPI. Test results The samples were characterized using TGA, FTIR, ASTM D 5035 and ASTM D 5587 tools. The results showed that, based on the thermal test (TGA) Sample A6 had a better thermal ability with a small mass degradation of 29% because AP treatment was able to degrade impurity and non-cellulose composition was higher than SC-AA treatment. Whereas in the functional group FTIR test at wave numbers 1030 cm-1 (C-O), 2300 cm-1 (O-H), 2900 cm-1 (C-H) showed a decrease in the percentage of transmittance in samples A4 and A6 compared to controls. The best results of the tensile and tear test for OPEFB fibers based on alkaline peroxide treatment, namely on 4-layer nonwovens, the larger the layer, the higher the tear and tensile strength. The best delignification is alkaline peroxide sample (180 minutes) and based on mechanical test of 4 layer nonwoven OPEFB fibers with gramassiere 1700 g/m2.
Keyword: Alkaline peroxide (AP), Delignification, Chemical components, Nonwoven, OPEFB fibers, Sodium chlorite-acetic acid (SC-AA)

Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model