Hasil Pencarian  ::  Simpan CSV :: Kembali

Abstrak :
Banyak penelitian ekstraksi silika dari sekam padi telah berhasil. Salah satu metode dengan metode sol-gel menggunakan reaktan NaOH dan asam kuat HCl. Larutan NaOH yang digunakan dengan konsentrasi 5 % dan 10 % serta larutan HCl yang digunakan sebanyak 1,5 M. Abu sekam padi yang digunakan adalah hasil pembakaran sekam padi sampai pada suhu 500oC. Proses Ekstraksi dilakukan dengan metode sol-gel menggunakan larutan NaOH selama 3 jam pada suhu ruang. Selanjutnya diendapkan dengan pengasaman menggunakan asam kuat hingga pH mencapai titik netral. Bahan yang dihasilkan adalah asam silikat yang berbentuk gel dan kemudian dikeringkan. Silika yang telah dikeringkan kemudian dianalisis menggunakan SEM, XRD dan ICP.Hasil penelitian SEM dan XRD akan menilai ukuran partikel silika dan struktur fasa. Sedangkan ICP akan mengetahui jumlah pengotor yang ada dalam partikel silika. Penelitian ini bermanfaat dalam meningkatkan efektifitas dari proses esktraksi silika dari sekam padi khususnya metode sol-gel. ......Many studies of silica extraction from rice husks have been successful. One method is the sol-gel method using NaOH and strong acid HCl as reactants. NaOH solution used with a concentration of 5% and 10% and HCl solution used as much as 1.5 M. Rice husk ash used is the result of burning rice husks to a temperature of 500oC. The extraction process was carried out by the sol-gel method using NaOH solution for 3 hours at room temperature. Then it is precipitated by acidification using a strong acid until the pH reaches a neutral point. The resulting material is silicic acid in the form of a gel and then dried. The dried silica was then analyzed using SEM, XRD and ICP. The results show that the weight percentage is silica (SiO2). This research is useful in increasing the effectiveness of the silica extraction process from rice husks.

Abstrak :
[ABSTRAK
Telah dilakukan penelitian pembuatan beton ringan atau lightweight concrete (LWC) menggunakan batu apug (BA) dan abu sekam padi (ASP). Sampel beton ringan yang dibuat mengandung BA dengan fraksi berbeda, adapun material semen, pasir, dan abu sekam padi volumenya dijaga tetap. Terdapat dua parameter utama yang menentukan sifat mekanik sampel LWC masing-masing adalah densitas sampel dan rasio air/semen (w/c). Sifat mekanik yang paling utama dari LWC adalah kekuatan tekan. Pada campuran dengan fraksi volume batu apung terbesar (100%) menghasilkan densitas dan kekuatan tekan paling rendah masing-masing sebesar (1389,6 kg/m3 dan 11,1 MPa). Diketahui bahwa makin rendah fraksi batu apung dalam sampel beton makin tinggi nilai densitas dan kekuatan tekannya, disebabkan oleh tingginya nilai fraksi pori baik pori terbuka maupun pori tertutup dalam sampel beton. Observasi terhadap fotomikro SEM batu apung menunjukkan bahwa terdapat sejumlah besar pori dengan bentuk memanjang ke bagian dalam dari permukaan sampel beton. Pori hadir dengan kerapatan jumlah pori relatif besar serta dengan ukuran yang bervariasi. Fakta ini menjelaskan mengapa batu apung besifat ringan karena memiliki densitas massa yang rendah. Pola difraksi sinar X sampel beton ringan memperlihatkan dominasi fasa kristalin diidentifikasi sebagai fasa quartz (SiO2). Namun dapat dipastikan sampel beton ringan terdiri dari fasa campuran antara fasa kristalin dan dengan sedikit fasa amorph. Fotomikro SEM beton ringan menunjukkan bahwa senyawa Kalsium Silikat Hidrat (CSH) mulai tumbuh pada waktu awal proses hidrasi dan terus berkembang sampai umur beton mencapai umur hidrasi 28 hari yang ditandai dengan sifat fisik yang padat dan peningkatan kekuatan beton. Dapat dipastikan bahwa senyawa CSH ini memiliki peranan penting terhadap pengaturan sifat mekanik seperti kekuatan tekan. Penelitian ini menyimpulkan bahwa batu apung dan abu sekam padi adalah material berbasis silika amorph yang memiliki densitas lebih rendah terutama dibandingkan dengan material pembentuk beton lainnya. Baik densitas dan kekuatan tekan sampel beton ringan ditentukan oleh rasio antara batu apung dan abu sekam padi. Ditemukan rasio terkecil BA/ASP yaitu 8 menghasilkan nilai densitas dan kekuatan tekan optimal, masing-masing pada usia beton 28 hari sebesar 1891 kg/m3 dan 23 MPa. Komposisi beton ringan yang terbaik diperoleh dari hasil penelitian ini adalah komposisi campuran PCC (1,00) : Pasir (1,00) : ASP (0,05) : BA (0,50) dengan nilai Slump 8 cm ditandai oleh nilai rasio antara kuat tekan dan densitas tertinggi adalah 1285.;

---

ABSTRACT
Research studies on the manufacture of lightweight concrete (LWC) using pumice and rice husk ash (RHA) materials have been done. LWC samples were made of pumice materials with a different mass fraction, while the cement, sand, and rice husk ash materials were keep fixed. It was found that there are two main parameters that determine the mechanical properties of LWC which are density and the water and cement ratio (w/c ratio). The main mechanical properties of LWC sample is the power press. Samples with the largest volume fraction of pumice (100%) resulted in lightest density (1389.6 kg/m3) and the smallest strength of LWC (11.1 MPa). It was found that, the lower the mass fraction of pumice in LWC samples, the higher the density values and compressive strength were obtained. This was caused by the high mas fraction value of pores, which were both open and closed pores. Scanning electron micorscopy (SEM) images for the pumice showed that the there are a large number of regular and structured pores extending deep inside the surface of the sample. It was observed that pores present with pore size does not vary significantly but with the density of the relatively large number of pores, indicating pumice has a low mass density. The XRD pattern of the lightweight concrete samples indicated that the samples were dominated by crystalline phases in which the quartz (SiO2) is the main phase and a small fraction of amorphous phase was also obtained. SEM images of lightweight concrete samples showed that the structure of Calcium Silicate Hydrates (CSH) started growing at the beginning of hydration time and continue to evolve into a more solid structure until the age of 28 days, where the compound has an important role to the mechanical properties such as compressive strength. The study concluded that the pumice and rice husk ash is are amorphous silica-based material which has a lower density compared to other concrete forming material such as cement and sands. Both density and light weight concrete compressive strength are determined by the ratio between pumice and rice husk ash, in which the smallest ratio 8 resulted in the largest density and compressive strength, which are 1890.5 kg/m3 and 23.2 MPa respectively at the age of 28 days. The study concluded that the best composition for lightweight concrete samples was the following: PCC (1,00): Sand (1,00): ASP (0,05): BA (0,50) with a slump value of 8 cm resulted in the largest value of a ratio between compressive strength and density of 1285.;Research studies on the manufacture of lightweight concrete (LWC) using pumice and rice husk ash (RHA) materials have been done. LWC samples were made of pumice materials with a different mass fraction, while the cement, sand, and rice husk ash materials were keep fixed. It was found that there are two main parameters that determine the mechanical properties of LWC which are density and the water and cement ratio (w/c ratio). The main mechanical properties of LWC sample is the power press. Samples with the largest volume fraction of pumice (100%) resulted in lightest density (1389.6 kg/m3) and the smallest strength of LWC (11.1 MPa). It was found that, the lower the mass fraction of pumice in LWC samples, the higher the density values and compressive strength were obtained. This was caused by the high mas fraction value of pores, which were both open and closed pores. Scanning electron micorscopy (SEM) images for the pumice showed that the there are a large number of regular and structured pores extending deep inside the surface of the sample. It was observed that pores present with pore size does not vary significantly but with the density of the relatively large number of pores, indicating pumice has a low mass density. The XRD pattern of the lightweight concrete samples indicated that the samples were dominated by crystalline phases in which the quartz (SiO2) is the main phase and a small fraction of amorphous phase was also obtained. SEM images of lightweight concrete samples showed that the structure of Calcium Silicate Hydrates (CSH) started growing at the beginning of hydration time and continue to evolve into a more solid structure until the age of 28 days, where the compound has an important role to the mechanical properties such as compressive strength. The study concluded that the pumice and rice husk ash is are amorphous silica-based material which has a lower density compared to other concrete forming material such as cement and sands. Both density and light weight concrete compressive strength are determined by the ratio between pumice and rice husk ash, in which the smallest ratio 8 resulted in the largest density and compressive strength, which are 1890.5 kg/m3 and 23.2 MPa respectively at the age of 28 days. The study concluded that the best composition for lightweight concrete samples was the following: PCC (1,00): Sand (1,00): ASP (0,05): BA (0,50) with a slump value of 8 cm resulted in the largest value of a ratio between compressive strength and density of 1285., Research studies on the manufacture of lightweight concrete (LWC) using pumice and rice husk ash (RHA) materials have been done. LWC samples were made of pumice materials with a different mass fraction, while the cement, sand, and rice husk ash materials were keep fixed. It was found that there are two main parameters that determine the mechanical properties of LWC which are density and the water and cement ratio (w/c ratio). The main mechanical properties of LWC sample is the power press. Samples with the largest volume fraction of pumice (100%) resulted in lightest density (1389.6 kg/m3) and the smallest strength of LWC (11.1 MPa). It was found that, the lower the mass fraction of pumice in LWC samples, the higher the density values and compressive strength were obtained. This was caused by the high mas fraction value of pores, which were both open and closed pores. Scanning electron micorscopy (SEM) images for the pumice showed that the there are a large number of regular and structured pores extending deep inside the surface of the sample. It was observed that pores present with pore size does not vary significantly but with the density of the relatively large number of pores, indicating pumice has a low mass density. The XRD pattern of the lightweight concrete samples indicated that the samples were dominated by crystalline phases in which the quartz (SiO2) is the main phase and a small fraction of amorphous phase was also obtained. SEM images of lightweight concrete samples showed that the structure of Calcium Silicate Hydrates (CSH) started growing at the beginning of hydration time and continue to evolve into a more solid structure until the age of 28 days, where the compound has an important role to the mechanical properties such as compressive strength. The study concluded that the pumice and rice husk ash is are amorphous silica-based material which has a lower density compared to other concrete forming material such as cement and sands. Both density and light weight concrete compressive strength are determined by the ratio between pumice and rice husk ash, in which the smallest ratio 8 resulted in the largest density and compressive strength, which are 1890.5 kg/m3 and 23.2 MPa respectively at the age of 28 days. The study concluded that the best composition for lightweight concrete samples was the following: PCC (1,00): Sand (1,00): ASP (0,05): BA (0,50) with a slump value of 8 cm resulted in the largest value of a ratio between compressive strength and density of 1285.]

Abstrak :
Sekam padi merupakan limbah pertanian yang sangat banyak jumlahnya di negara penghasil beras. Pada tahun 2015, Indonesia sebagai negara penghasil beras memproduksi padi sebanyak 75 juta ton dan sekitar 20-25 dari berat total padi adalah sekam padi. Akumulasi dari limbah sekam padi yang sangat banyak ini dapat menjadi ancaman bagi lingkungan. Salah satu cara untuk mengurangi akumulasi dari limbah tersebut ialah dengan memanfaatkan limbah tersebut. Sekam padi mengandung silika dengan nilai sekitar 20-25 dari berat total sekam padi. Silika memiliki banyak aplikasi dalam industri gelas, keramik, dan semen. Pada penelitian ini silika diesktraksi dari abu sekam padi menggunakan metode alkali yang disertai dengan proses refluks. Abu sekam padi direfluks menggunakan larutan NaOH dengan konsentrasi 5, dan 10 selama 1 jam pada temperatur 80 C. Proses ini menghasilkan larutan Sodium Silikat Na2SiO3. Selanjutnya, asam HCl atau CH3COOH ditambahkan secara perlahan ke dalam larutan sodium silikat disertai dengan pengadukan dengan kecepatan konstan. Proses ini akan menghasilkan silika gel. Silika gel yang terbentuk diisolasi pada temperatur 30 C selama 18 jam. Selanjutnya, silika gel dipanaskan selama 12 jam dengan temperatur 120 C. Proses ini akan menghasilkan xerogel. Xerogel kemudian dikarakterisasi. Metode karakterisasi material yang digunakan ialah X-ray Diffraction XRD, Fourier transform infrared FTIR, Braun Emmet Teller BET, dan Energy Dispersive X-Ray EDX. Hasil penelitian menunjukkan bahwa silika yang diekstraksi dari sekam padi banyak mengandung unsur Si dan O. Berdasarkan hasil analisis XRD, silika yang dihasilkan dari sekam padi merupakan silika amorf, dan berdasarkan hasil analisis FT-IR, terdapat vibrasi tekuk dan ulur Si-O dalam serbuk silika. Silika dengan pengasaman menggunakan asam HCl memiliki luas permukaan sebesar 236,2 m2/g. Sementara silika dengan pengasaman menggunakan asam CH3COOH memiliki luas permukaan sebesar 204,8 m2/g. Silika yang diasamkan dengan HCl memiliki yield tertinggi yaitu sebesar 74,9 yang didapatkan dari rasio antara 3,745 gr massa xerogel dengan 5 gr massa abu sekam padi. Silika yang diasamkan dengan CH3COOH memiliki yield terendah yaitu sebesar 60,06 yang didapatkan dari rasio antara 3,003 gr massa xerogel dengan 5 gr massa abu sekam padi.

---

Rice Husk RH is an enormous agricultural waste in rice producing country. In 2015, Indonesia, a rice producing country, produced paddy about 75 million tons, and about 20 22 of total weight of paddy is rice husk. The accumulations of these huge amount of rice husk waste can be environmental threat. One of the solution to reduce these accumulations is to utilize these wastes. Rice husk contains silica in the range of 20 ndash 25 wt. Silica has many applications in the glass, ceramics, and cement industries. In this study, silica was extracted from rice husk using alkaline extraction method with reflux process and it was followed by acidification. In this study, rice husks ash RHA was refluxed by aqueous NaOH with concentration 5 and 10, for 1 hour at 80 C. This process produced Sodium Silicate solution Na2SiO3. Next, HCl or CH3COOH acid was added dropwise into the sodium silicate solution under constant stirring condition until pH 7. This process produced wet gel silica. The silica gel obtained was isolated at 30 C for 18 hours. Then, it was heated to 120 C for 12 hours to produce xerogel. Next, xerogel was characterized. The Characterization methods which were used in this study are X ray Diffraction XRD, Fourier transform infrared FTIR , Braun Emmet Teller BET, and Energy Dispersive X Ray EDX. The results showed that silica which was extracted from rice husks contains many Si and O elements. Based on XRD analysis, silica produced from rice husk ash is an amorphous silica and based on FT IR analysis, it has bending and stretching vibration of Si O. Silica with HCl acidification has a surface area 236.2 m2 g. In the other hand, silica with CH3COOH acidification has a surface area 204.8 m2 g. Silica which acidified by HCl has the highest yield, that is about 74.9 which was obtained from ratio between 3.745 gr mass of xerogel and 5 gr mass of RHA. Silica which acidified by CH3COOH has the lowest yield, that is about 60.06 which was obtained from ratio between 3.003 gr mass of xerogel and 5 gr mass of RHA. Keywords Rice husk ash Silica Alkaline extraction Reflux process Xerogel.

Abstrak :

Tingkat konsumsi nasi yang tinggi di Indonesia menuntut adanya tingkat produksi beras yang tinggi pula yang tentunya akan menghasilkan limbah. Salah satu limbah industri beras yang kurang pemanfaatannya adalah abu sekam padi. Abu sekam padi memiliki kandungan silika yang tinggi sehingga marak dilakukannya penelitian mengenai ekstraksi silika dengan sekam padi atau abu sekam padi sebagai sumbernya. SiO₂ yang didapatkan dari ekstraksi abu sekam padi memiliki banyak manfaat, salah satunya adalah sebagai material pendukung yang dapat meningkatkan performa fotokatalis. Dalam penelitian ini, SiO₂ yang diekstrak dari abu sekam padi disintesis bersama dengan g-C₃N₄ untuk membentuk komposit g-C₃N₄/SiO₂. Komposit g-C₃N₄/SiO₂ hasil sintesis dikarakterisasi menggunakan SEM/EDX (Scanning Electron Microscopy/Energi-Dispersive X-Ray), UV-Vis DRS (Ultraviolet-Visible Diffuse Reflectance Spectroscopy), dan FT-IR (Fourier Transform Infra-Red). Pengujian sifat swa-bersih dan anti-kabut komposit dilakukan dengan mengukur sudut kontak menggunakan contact angle meter dan menghitung pengurangan pengotor. Hasil uji menunjukkan bahwa g-C₃N₄/SiO­₂ dengan rasio 1:1 memiliki hasil paling optimal dengan sudut kontak terkecil, yaitu 3°, dan pengurangan pengotor terbanyak, yaitu 66,5%. ......The high level of rice consumption in Indonesia demands a high level of rice production which of course will produce waste. One of the wastes in rice industry that is still underutilized is rice husk ash. Rice husk ash has a high silica content, so there is a lot of research on silica extraction using rice husk ash or rice husk ash as the source. SiO₂ obtained from rice husk ash extraction has many benefits, one of which is as a supporting material that can improve photocatalyst performance. In this study, SiO₂ extracted from rice husk ash was synthesized together with g-C₃N₄ to form a g-C₃N₄/SiO₂ composite. The synthesized SiO₂/g-C₃N₄ composite was characterized using SEM/EDX (Scanning Electron Microscopy/Energy-Dispersive X-Ray), UV-Vis DRS (Ultraviolet-Visible Diffuse Reflectance Spectroscopy), and FT-IR (Fourier Transform Infra-Red). Testing of the self-cleaning and anti-fog properties of the composite was carried out by measuring the contact angle using a contact angle meter and calculating the reduction in impurities. The test results show that g-C₃N₄/SiO₂ with a ratio of 1:1 has the most optimal results with the smallest contact angle, which is 3°, and the highest reduction of impurities, which is 66,5%.

Abstrak :
Menurut survey Badan Pusat Statistik di Indonesia diketahui telah terjadi pertumbuhan nilai konstruksi di Kalimantan Timur (lokasi baru Ibu Kota Negara) sebesar 6,60% dari tahun 2019-2020. Semakin tinggi nilai konstruksi maka semakin tinggi pula permintaan bahan bangunan, contohnya seperti mortar semen portland. Akan tetapi, terdapat dampak buruk dalam pemakaian semen portland yang secara terus-menerus yaitu terjadinya pemanasan global karena adanya emisi gas CO yang tinggi. Untuk mengurangi dampak buruk tersebut diperlukanlah bahan pengganti semen yang lebih ramah lingkungan seperti material geopolimer. Dalam pembentukan mortar geopolimer dibutuhkan bahan utama yang mengandung kadar Si dan Al yang tinggi seperti ASP dan zeolit, serta perlu adanya alkali aktivator seperti NaOH dan NaSiO yang berperan sebagai larutan pengikat unsur Si dan Al dalam reaksi geopolimerisasi. Ada perlakuan khusus pada studi ini untuk menjaga kualitas mortar geopolimer ASP-Zeolit yang terbentuk yaitu metode dengan oven di suhu 60°C selama 24 jam. Pada studi ini dilakukan pembentukan mortar geopolimer dengan lima variasi komposisi penyusun mortar geopolimer antara lain 100%ASP; 90%ASP-10%Zeolit; 70%ASP-30%Zeolit; 50%ASP-50%Zeolit; dan 100%Zeolit, untuk mengetahui pengaruh kadar prekursor terhadap nilai kuat tekan mortar tersebut serta membandingkan nilai kuat tekan mortar geopolimer dengan kuat tekan mortar semen portland. Hasil penelitian ini menunjukkan adanya kandungan Si yang tinggi dalam bahan penyusun mortar geopolimer akan meningkatkan nilai kuat tekannya seperti mortar geopolimer 100%ASP, tetapi nilai kuat tekan mortar geopolimer ASP-Zeolit masih dibawah nilai kuat tekan mortar semen portland. ......According to a survey conducted by Indonesia's Central Statistics Agency, East Kalimantan (the new location for the State Capital of Indonesia) saw a 6,60% increase in construction value between 2019 and 2020. The higher the construction value, the higher the demand for building materials, such as portland cement mortar. However, there are negative impacts in the continuous use of portland cement which causes a global warming effect due to high CO2 gas emissions. To reduce these negative impacts, a more environmentally friendly cement substitute material, such as geopolymer material, is needed. In the formation of geopolymer mortar, the main ingredients that contain high levels of Si and Al are needed, such as RHA and zeolite, as well as the need for alkaline activators such as NaOH and Na2SiO3 which act as a binding solution for Si and Al elements in the geopolymerization reaction. There is special treatment in this study to maintain the quality of RHA-Zeolite geopolymer mortar that is formed namely curing oven at 60°C for 24 hours. In this study, geopolymer mortar was formed with five variations of geopolymer mortar composition, including 100% RHA; 90% RHA-10% Zeolite; 70% RHA-30% Zeolite; 50% RHA-50% Zeolite; and 100% Zeolite, to determine the effect of precursor content on the compressive strength of the mortar and to compare the compressive strength of this geopolymer mortar with the compressive strength of portland cement mortar. The results of this study indicate that a high Si content in the RHA-Zeolite geopolymer mortar will increase its compressive strength like 100% RHA geopolymer mortar, but the compressive strength of RHA-Zeolite geopolymer mortar is still below the compressive strength of portland cement mortar.

Abstrak :
ABSTRAK
Mortar yang terbuat dari semen dan agregat halus dengan perbandingan 1:4, dimodifikasi dengan menambahkan abu sekam padi sebagai material subtitusi parsial yang menggantikan sejumlah proporsi agregat halus sebesar 10%, 20%, 30% dan 40% dari berat agregat halus. Serangkaian uji coba di laboratorium dilakukan untuk melihat pengaruhnya terhadap kuat tekan, modulus elastisitas dan permeabilitas mortar. Hasil evaluasi data hingga saat ini memberikan kesimpulan sebagai berikut : 1. Penggunaan abu sekam padi dalam campuran mortar mengakibatkan terjadinya penurunan kekuatan mortar. Semakin banyak penggunaan abu sekam padi semakin besar penurunan kekuatan mortar. 2. Penggunaan abu sekam padi pada campuran mortar menurunkan modulus elastisitas mortar. Semakin banyak penggunaan abu sekam padi semakin besar penurunan modulus elastisitas mortar. 3. Penggunaan abu sekam padi pada campuran mortar menaikkan permeabilitas mortar. Semakin banyak penggunaan abu sekam padi semakin besar permeabilitas mortar.

Abstrak :
Penggunaan batubara sebagai bahan bakar yang semakin meningkat di seluruh dunia membutuhkan perhatian secepatnya dari beberapa peneliti. Fokus penelitian ini melakukan sintesis zeolit ZSM-5 menggunakan abu terbang batubara (rasio mol SiO2 /Al2O3 = 3,59). sebagai bahan baku utama. Dalam rangka untuk mendapatkan rasio mol SiO2/Al2O3 yang tepat, digunakan silikat dibuat dari sekam padi. Pertam-tama abu terbang batubara dan abu sekam padi dilakukan pre-treatment untuk mendapatkan ekstrak silikat (SiO4 4-) dan aluminat (AlO4 5-) dan dipisahkan dari pengotor-pengotornya. Kemudian zeolit ZSM-5 mesopori disintesis menggunakan metode hidrotermal dengan dua jenis template (TPAOH dan PDDA) dan dengan benih ZSM-5 dengan ratio mol 12 NaOH : 30 SiO2 : 0,75 Al2O3 : 1800 H2O. Hasil sintesis zeolit ZSM-5 mesopori dikarakterisasi dengan FTIR, XRD, SEM-EDX, AAS, TGA dan BET. Hasil sintesis ZSM-5 dari abu terbang batubara dan abu sekam padi juga dibandingkan dengan ZSM-5 hasil sintesis dari bahan pro-analisis. Hasil FTIR menunjukkan puncak pada bilangan gelombang pada 1250-950 cm-1 (νasymetric T-O), 820-650 cm-1 (νsymetric T-O), and at 650-500 cm-1 (double ring) yang merupakan jalinan eksternal gugus pentasil. Dari hasil XRD terlihat munculnya puncak pada posisi 2 theta pada 7-10 0 dan 22-25 0, yang merupakan puncak khas dari zeolit ZSM-5, selain itu juga muncul pola menunjukkan hematite dan magnetite dengan intensitas rendah. Hasil SEM menunjukkan kristal heksagonal yang tidak merata yang mengindikasi terbentuknya mesopori pada kristal ZSM-5, tetapi dari hasil SEM juga terlihat masih banyak terdapatnya pengotor pada hasil sintesis. Analisa AAS dan EDX menunjukkan ratio Si/Al ZSM-5 double template sebesar 20,10 dan ZSM-5 dengan benih sebesar 15,95. ZSM-5 hasil sintesis dari campuran abu terbang batubara dan abu sekam padi (SA ZSM-5 double template =43,76 m2/g dan SA ZSM-5 benih = 45,95 m2/g) memiliki luas permukaan yang lebih rendah dibandingkan dengan ZSM-5 hasil sintesis dari bahan pro-analisis (SA=294,75 m2/g). Selanjutnya, ZSM-5 hasil sintesis diimpregnasi dengan ion kobalt (III) dan dikalsinasi pada 550 oC menjadi spesi kobalt-oksida (Co/ZSM-5). Uji aktivitas katalitik ZSM-5 dan Co/ZSM-5 sebagai katalis heterogen pada reaksi partial oksidasi metana menjadi metanol dan juga dibandingkan dengan ZSM-5 komersial. Dari uji aktivitas katalitik meskipun % konversi metana menjadi metanol ZSM-5 hasil sintesis dari campuran abu terbang batubara dan abu sekam padi masih inferior ( ZSM-5 double template = 7,08% dan 12,43% ; ZSM-5 benih = 10,54% dan 11,19 % konversi metana) dibandingkan hasil sintesis dari precursor pro-analitik (28,33% dan 37,65%) and ZSM-5 komersial (9,92% dan 21,36%), tetapi ZSM-5 dan Co/ZSM-5 yang berasal dari abu terbang batubara dan abu sekam padi berpotensi digunakan sebagai katalis pada reaksi partial oksidasi metana menjadi metanol. ......The ever increasing consumption of coal around the world has given rise to the by-product coal fly ash that requires an urgent attention and is gaining much needed research attention. Focus of this work has the synthesis of ZSM-5 zeolite using fly ash (SiO2/Al2O3 mole ratio = 3.59). as the main raw material. In order to obtain the appropriate SiO2/Al2O3 mole ratio, the silicate prepared from rice husk was used. First, coal fly ash and rice husk were subjected to pre-treatment in order to extract silicate (SiO4 4-) and aluminate (AlO4 5-) and separated from the impurities. Then the ZSM-5 zeolite were synthesized through hydrothermal treatment using two types of templates (TPAOH and PDDA) and using seed of ZSM-5 giving molar ratio 12 NaOH : 30 SiO2 : 0.75 Al2O3 : 1800 H2O. The as-synthesized ZSM-5 was then characterized using FTIR, XRD, SEM-EDX, and BET. The as-synthesized ZSM-5 from fly ash and rice husk also was compared with ZSM-5 from pro-analysis material. The result of FTIR showed peaks at 1250-950 cm-1 (νasymetric T-O), 820-650 cm-1 (νsymetric T-O), and at 650-500 cm-1 confirming the presence of the five number ring of the pentasil structure. The result of XRD showed the appearance of certain peaks in the position 2 theta between 7-90 and 22-250 indicative of ZSM-5 structure, but also showed the pattern of low intensity magnetite and hematite. The SEM image showed the rough surface of hexagonal crystals from ZSM-5 structure, indicative of mesoporosity in the structure, but SEM image also showed still many impurities. Furthermore, the EDX result showed variation in Si/Al ratio, and in which the ratio in the ZSM-5 double template is 20.10 ; ZSM-5 from pro-analysis materials is 16.73 and ZSM-5 seeded is 15.95 . ZSM-5 from fly ash and rice husk (SA ZSM-5 double template =43.76 m2/g and SA ZSM-5 seeded = 45.95 m2/g) has lower surface area than ZSM-5 from pro-analisys material (SA=294,75 m2/g). After ZSM-5 was synthesized, it was modified with Cobalt through impregnation method. The catalytic activity of both ZSM-5 and Co/ZSM-5 zeolites as heterogeneous catalysts in partial oxidation of methane were preliminary tested and compared with that commercial one. The result showed that hence the catalytic activity of ZSM-5 and Co/ZSM-5 from fly ash and rice husk was still inferior ( ZSM-5 double template is 7.08% and 12.43% ; ZSM-5 seeded is 10.54% and 11.19 % conversion of methane) compared tothe pro-analysis sourced-counterpart (28.33% and 37.65%) and commercial one (9.92% and 21.36%), they were potential to be used as catalyst in the partial oxidation of methane to methanol.

Abstrak :
Skripsi ini membahas tentang penggunaan Abu Sekam Padi (RHA) sebagai bahan substitusi perekat semen dan penggunaan Limbah Adukan Beton (CSW) sebagai agregat halus untuk mengurangi penggunaan jumlah pasir pada beton. Penelitian dilakukan dengan membuat mix design dari beton normal fc' 25 MPa dan dikembangkan pada lima variasi campuran dengan jumlah CSW 30%, 40%, 50%, 60% dan 70% dengan penggunaan RHA tetap yaitu 8% dai total pemakaian semen. Sifat mekanis beton yang diuji meliputi: kuat tekan, modulus elastisitas, densitas, permeabilitas. Pengujian kuat tekan dilakukan pada umur 3, 7, 14, 21, 28, 56 dan 90 hari terhadap lima benda uji pada setiap umur pengujian. Pada pengujian kuat tekan dan modulus elastisitas nilai optimum terjadi pada campuran dengan jumlah CSW 30%, sedangkan prosentase susut terbesar terjadi pada beton dengan campuran CSW 70%. Dari penelitia ini diharapkan beton dengan campuran RHA dan CSW menghasilkan mutu sesuai yang direncanakan dan dapat diaplikasikan untuk produk paving blok.

---

The focus of the study is observing the use of Rice Husk Ash (RHA) as a substitute of portland cement and Concrete Sludge Waste (CSW) to reduce of sand in concrete.Refers to the mix design of normal concrete fc' 25 MPa the mechanical properties tested in five variations with a percentage of CSW 30%, 40%, 50%, 60%, 70% and using fixed number 8% of RHA. The concrete were tested compressive strength, modulus of elasticity, density, and permeability at the age of 3, 7, 14, 21, 28, 56 and 90 days for five specimens at each age of test. From the testing of compressive strength, modulus of elasticity obtained an optimum number of CSW 30%. And teh largest percentage of shrinkage occured in CSW 70%. From the result has been obtained, the concrete with RHA and CSW produce quality as planned and can be applied to block paving products, could be applied to the road pavement.