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Abstrak :
Nanopartikel oksida seng (ZnO) yang diberi dopan kromium (Cr) dan penambahan 10 % montmorillonite (MMT) disintesis dengan metode kopresipitasi untuk empat variasi persen atom Cr. Nanopartikel dikarakterisasi menggunakan X-Ray Diffraction (XRD), Energy Dispersive X-Ray (EDX), Fourier Transform Infrared (FTIR), UV-Visible Diffuse Reflectance (UV-Vis) dan Electronic Spin Resonance (ESR). Pengujian aktivitas fotokatalitik dilakukan menggunakan model polutan methylene blue dengan paparan sinar UV. Penambahan montmorillonite dan dopan Cr pada ZnO dapat meningkatkan degradasi methylene blue dengan Cr doped ZnO/MMT 10 at.% menunjukkan degradasi maksimum dengan kondisi optimum dosis fotokatalis 0.7 g/L dan konsenstrasi larutan 20 mg/L. Spesies dominan pada aktivitas fotokatalitik adalah hole dan OH● berturut-turut. ......Chromium (Cr) doped zinc oxide (ZnO) nanoparticles with 10% montmorillonite (MMT) addition were synthesized by co-precipitation method for four chrome atomic percentage variations. Samples were characterized by X-Ray Diffraction (XRD), Energy Dispersive X-Ray (EDX), Fourier Transform Infrared (FTIR), UV-Visible Diffuse Reflectance (UV-Vis) and Electronic Spin Resonance (ESR). Photocatalytic were evaluated using methylene blue under UV light irradiation. MMT addition and Cr dopant to ZnO nanoparticles enhance methylene blue degradation with the optimum conditions are 0.7 g/L of nanoparticle and 20 mg/L of methylene blue initial concentration. Hole and OH● were identified as dominant species of photocatalytic activity.

Abstrak :
Superabsorben nanokomposit berbasis natrium alginat tercangkok poli akrilat-co-akrilamida yang dikompositkan dengan montmorillonite MMT , dan dengan penambahan pupuk NPK ke dalam superabsorben nanokomposit dengan metode polimerisasi in situ telah berhasil disintesis pada panelitian ini. Pada awal penelitian dilakukan isolasi natrium alginat dari ganggang coklat dengan persen rendemen rata-rata yang diperoleh sebesar 44,26 . Selanjutnya, natrium alginat hasil isolasi dikopolimerisasi dengan menggunakan asam akrilat dan akrilamida sebagai monomer, kalium persulfat sebagai inisiator, N,N '; metilen-bis-akrilamida MBA sebagai agen pengikat silang dan ditambahkan MMT untuk memperkuat sifat fisik dari superabsorben nanokomposit. Superabsorben nanokomposit dikarakterisasi dengan instrumen FTIR untuk analisis gugus fungsi, XRD untuk analisis indeks kristanilitas, dan SEM untuk melihat morfologi permukaan. Kapasitas swelling air, urea, KH2PO4, dan NH4 H2PO4 superabsorben nanokomposit natrium alginat menunjukkan nilai kapasitas terbaik, yaitu berturut-turut sebesar 475.8 g/g, 491.1 g/g, 122.9 g/g, dan 134.9 g/g. Kapasitas release air, urea, KH2PO4, dan NH4 H2PO4 superabsorben nanokomposit natrium alginat menunjukkan nilai kapasitas terbaik, yaitu berturut-turut sebesar 70.9 , 69.8 , 52.6 , dan 48.6 . Kapasitas swelling optimum superabsorben nanokomposit pupuk lepas lambat dengan in situ urea, KH2PO4, NH4 H2PO4, yaitu berturut - turut sebesar 423.3 g/g, 89.8 g/g, dan 138.1 g/g. Kapasitas release optimum superabsorben nanokomposit pupuk lepas lambat dengan in situ urea, KH2PO4, NH4 H2PO4, yaitu berturut - turut sebesar 55.0 , 35.3 , 28.2 . Kinetika orde swelling optimum SA9 FD terhadap larutan air, urea, KH2PO4, dan NH4 H2PO4 mengikuti hukum laju orde pseudo-pertama. Kinetika orde release optimum SA9 FD terhadap larutan KH2PO4, dan NH4 H2PO4 mengikuti hukum laju orde pseudo-pertama, sedangkan kinetika orde release optimum SA9 FD terhadap larutan air dan urea mengikuti hukum laju orde pseudo-kedua. Kinetika orde swelling optimum superabsorben nanokomposit pupuk lepas lambat in situ KH2PO4 SA17 FD terhadap air mengikuti hukum laju orde pseudo-pertama, sedangkan kinetika orde swelling optimum superabsorben nanokomposit pupuk lepas lambat in situ urea SA14 FD , dan in situ NH4 H2PO4 SA20 FD mengikuti hukum laju orde pseudo-kedua. Kinetika orde release optimum SA14 FD dan SA20 FD terhadap larutan NaCl 0.9 mengikuti hukum laju orde pseudo-pertama, sedangkan kinetika orde release optimum SA17 FD mengikuti hukum laju orde pseudo-kedua. Hukum laju reaksi orde pseudo-pertama mengikuti persamaan v=k[absorbat]^1, sedangkan hukum laju reaksi orde pseudo-kedua mengikuti persamaan v=k[absorbat]^2. ...... Superabsorbent nanocomposite based sodium alginate grafted poly acrylate co acrylamide composited with montmorillonite MMT , and with the addition of NPK fertilizers into superabsorbent nanocomposite by in situ polymerization methods have been successfully synthesized in this study. At the beginning of the study, the isolation of sodium alginate from brown algae with percentage of average yield was 44,26 . Furthermore, the isolated sodium alginate was copolymerized using acrylic acid and acrylamide as monomer, potassium persulfate as initiator, N, N 39 methylene bis acrylamide MBA as a crosslinking agent and MMT was added to enhance the physical properties of the superabsorbent nanocomposite. Superabsorbent nanocomposite were characterized by FTIR instruments for functional group analysis, XRD for christanility index analysis, and SEM for viewing surface morphology. The swelling capacity of water, urea, KH2PO4, and NH4 H2PO4 superabsorbent nanocomposite sodium alginate show the best capacity value, ie 475,8 g g, 491,1 g g, 122,9 g g, and 134,9 g g, respectively. The release capacity of water, urea, KH2PO4, and NH4 H2PO4 superabsorbent nanocomposite sodium alginate show the best capacity, ie 70,9 , 69,8 , 52,6 and 48,6 , respectively. The optimum swelling capacity of slow release fertilizer superabsorbent nanocomposites with in situ urea, KH2PO4, NH4 H2PO4, ie 423,3 g g, 89,8 g g, and 138,1 g g, respectively. The optimum release capacity of slow release fertilizer superabsorbent nanocomposites with in situ urea, KH2PO4, NH4 H2PO4, ie 55.0 g g, 35,3 g g, 28,2 g g, respectively. The optimum swelling order kinetics of SA9 FD against water, urea, KH2PO4, and NH4 H2PO4 solution follows the pseudo first order rate law. The optimum release order kinetics of SA9 FD against KH2PO4, and NH4 H2PO4 solution follows the pseudo first order rate law, whereas the optimum release order kinetics of SA9 FD against water and urea solution follows the pseudo second order rate law. The optimum swelling order kinetics superabsorbent nanocomposite fertilizer slow release in situ KH2PO4 SA17 FD against the water follows the pseudo first order rate law, while the optimum swelling order kinetics superabsorbent nanocomposite fertilizer slow release in situ urea SA14 FD , and in situ NH4 H2PO4 SA20 FD follows the pseudo second order rate law. The optimum release order kinetics SA14 FD and SA20 FD against 0.9 NaCl solution follows the pseudo first order rate law, while the optimum release order kinetics SA17 FD follows the pseudo second order rate law. The pseudo first order reaction rate law follows the equation v k absorbat 1, while the pseudo second order reaction rate law follows the equation v k absorbat 2.

Abstrak :
Limbah minyak pelumas bekas dikategorikan sebagai limbah bahan berbahaya dan beracun B3 yang mengandung logam berat salah satunya Pb. Untuk mengurangi konsentrasi Pb dalam minyak pelumas bekas dan memperbaiki karakteristik minyak pelumas, dilakukan pengolahan dengan menggunakan lempung sebagai bleaching earth melaui proses adsorbsi. Pada penelitian ini, dilakukan karakterisasi awal minyak pelumas bekas dengan spesifikasi SAE 10W-30. Selanjutnya, untuk meningkatkan kemampuan lempung sebagai adsorban, lempung diaktivasi dengan kalsinasi pada temperatur 300, 450, dan 600°C. Hasil XRD menunjukkan terjadi peningkatan montmorillonite dalam lempung hingga 63. Kemudian proses adsorbsi dilakukan untuk mengetahui pengaruh perubahan mineral lempung terhadap kapasitas lempung dalam skala laboratorium dengan konsentrasi lempung 80 g/L. Temperatur adsorbsi adalah 120°C dengan waktu kontak 300 menit. Pada penelitian, diperoleh hasil bahwa adsorbsi timbal mencapai kondisi optimum pada penggunaan lempung teraktivasi kalsinasi 450°C dan konstan pada penggunaan lempung teraktivasi kalsinasi 600. Data isotherm adsorbsi menunjukkan kecocokan dengan model isoterm Freundlich dengan kapasitas adsorbsi 4,05x10-3 mg/g. Karakterisasi akhir minyak pelumas menunjukkan terjadinya perbaikan sifat fisik dan kimiawi minyak pelumas bekas setelah proses adsorbsi.

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Waste lubricant oil is categorized as hazardous waste which contains heavy metal such us lead. To reduce the amount of lead concentration and improve waste lubricant oil properties, the waste is treated with clay as bleaching earth through adsorption process. In this study, the physical and chemical properties of waste lubricant oil with specification SAE 10W 30 was analyzed before treated with clay. To enhance clays properties as adsorbent, the clay was activated with calcination at temperature 300, 450, and 600°C. XRD result showed that calcination process could increase montmorillonite percentage in clay, approximately 63. To determine the correlation between clay mineral structure and clay capacity as adsorbent, the adsorption process was conducted in laboratory scale with 80g L at each of activated clay. The adsorption temperature and contact time were 120°C and 300 minutes respectively. The experimental procedure gave result that lead adsorption reached its optimum condition with the used of activated clay at temperature 450 C and remained constact with 600°C calcined clay. Pb adsorption isotherm data showed compability with Freundlich isotherm model with adsorption capacity 4,05x10 3 mg g. The final characterization of treated waste lubricant oil indicated that there was improvement of its properties after adsorption process.