Alien Registration- Bouffard, Marie Anne Adilina (Biddeford, York County)

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A Review on the Hydroisomerisasion of n-Parafins over Supported Metal Catalysts

Catalytic hydroisomerization of n-paraffin aims to produce branched paraffin isomers and suppress cracking reactions in the production of the low cloud point of biodiesel. The development of the type of metal and catalyst support, amount of metal loading, and reaction conditions are important to increase the catalyst activity. A high performace catalyst for hydroisomerization bears bifunctional characteristics with a high level of hydrogenation active sites and low acidity, maximizing the progress of hydroisomerization compared to the competitive cracking reaction. In addition, a catalyst support with smaller pore size can hinder large molecular structure isoparaffins to react on the acid site in the pore thus providing good selectivity for converting n-paraffin. Catalysts loaded with noble metals (Pt or Pd) showed significantly higher selectivity for hydroisomerization than non-noble transition metals such as Ni, Co, Mo and W. The reaction temperature and contact time are also important parameters in hydroisomerization of long chain paraffin, because long contact times and high temperatures tend to produce undesired byproducts of cracking. This review reports several examples of supported metal catalyst used in the hydroisomerization of long chain hydrocarbon n-paraffins under optimized reaction conditions, providing the best isomerization selectivity results with the lowest amount of byproducts. The role of various metals and their supports will be explained mainly for bifunctional catalysts

TANGGAPAN SISWA TERHADAP KOMPETENSI PEDAGOGIK GURU JURUSAN ADMINISTASI PERKANTORAN SMK NEGERI 1 KLATEN.

TANGGAPAN SISWA TERHADAP KOMPETENSI PEDAGOGIK GURU JURUSAN ADMINISTASI PERKANTORAN SMK NEGERI 1 KLATEN Oleh: Adilina Hasibuan NIM 09402241041 ABSTRAK Penelitian ini bertujuan untuk mengetahui tanggapan siswa terhadap kompetensi pedagogik guru jurusan Administasi Perkantoran SMK N 1 Klaten. Penelitian ini merupakan penelitian deskriptif dengan teknik pengambilan data menggunakan angket. Populasi penelitian adalah seluruh siswa jurusan Administrasi Perkantoran kelas X, XI, dan XII SMKN 1 Klaten yang berjumlah 231 siswa. Jumlah sample sebanyak 90 siswa yang diambil dengan cara purposive sample. Kriteria penentuan sample adalah 90 siswa yang memiliki prestasi terbaik, terdiri dari 30 siswa kelas X, XI, dan XII. Teknik analisis data menggunakan analisis deskriptif kuantitatif dengan persentase. Hasil penelitian dari masing-masing indikator menunjukkan, (1) kemampuan memahami siswa berada pada kategori kurang memahami dengan jumlah frekuensi sebanyak 41 (45,56%), (2) kemampuan mengembangkan siswa berada pada kategori kurang baik dengan jumlah frekuensi sebanyak 42 (46,67%), (3) kemampuan merencanakan pembelajaran belum baik, (4) kemampuan melaksanakan proses pembelajaran berada pada kategori buruk dengan jumlah frekuensi sebanyak 45 (50%), dan (5) kemampuan menilai pembelajaran berada pada kategori kurang baik dengan jumlah ferekuensi sebanyak 50 (55,56%). Kata kunci: tanggapan siswa, kompetensi pedagogik, guru jurusan Administrasi Perkantoran

GREEN SYNTHESIS OF ISOPULEGOL FROM CITRONELLAL CATALYSED BY ZEOLITE BASED SOLID ACID CATALYSTS

Zeolit alam (NZ) telah dimodifikasi dengan penambahan asam (H-NZ) dan diaplikasikan sebagai katalis asam padat untuk green sintesis isopulehol dari minyak sereh wangi. Sintesis ini menlibatkan reaksi siklisasi sitronelal menjai disopulegol pada suhu 50 sampai 120oC. Aktivitas katalis H-NZ terbukti lebih tinggi dari katalis H-ZSM5 yang tersedia di pasar dan lebih unggul dari katalis asam padat berbasis bentonit. Perolehan terbaik sebesar 87% isopulegol diperoleh menggunakan katalis H-NZ pada 100oC selama 3 jam tanpa penggunaan pelarut reaksi

PATCHOULI ALCOHOL ENRICHMENT FROM PATCHOULI OIL USING MOLECULAR DISTILLATION UNIT

ABSTRACT Molecular distillation in the vacuum pressure about 10-3 mbar, temperature in the range of 80 oC – 100 oC, and wiper rate between 60 – 80 rpm was used for the separation and purification of patchouli oil. Patchouli oil has a large composition of patchouli alcohol which is usually used as a fixative for perfumery, cosmetics and pharmaceuticals. A large composition of patchouli alcohol usually is in the residue due to the high boiling point of this compound than others. Purification of patchouli alcohol increased with wiper rate and temperature but decreased with the feed rate. The temperature of liquid entering to the unit, feed rate and the wiping element bears on the distillation cylinder due to the centrifugal force and rolls over it bringing the liquid on the distillation cylinder into an intensive complex movement were the important technological parameters that determined distillation operation. Pursuant to condition above produced purification of patchouli alcohol due to the patchouli oil about 73.37%.   Keywords: Patchouli oil, molecular distillation, patchouli alcohol, separation, purification

ONE-POT SYNTESIS OF MENTHOL FROM CITRONELLAL : APPLICATION OF CITRONELLA OIL

ABSTRACTSynthesis of menthol (C10H20O) from citronellal (C10H18O) has been performed by a one-pot process. The process was conducted in a 250 mL capacity autoclave with acidified natural zeolite and Raney Nickel as catalysts at temperature 120°C, pressure 5 bar, and variation of time 1-8 hours. Natural zeolite and Raney Nickel were placed in the autoclave and it was found that the cyclisation and hydrogenation reaction to form menthol could undergo in the same reactor. FTIR Analysis showed peak formation at 3346.50 cm-1 indicating –OH group was formed. Result of 1H-NMR and 13C-NMR analysis reports chemical shifts at δ=71.53 ppm and  δ=4.05 ppm. Gas chromatography analysis showed that the conversion was 80% with concentration of menthol about 68% (v/v). Keywords : menthol, citronellal, one-pot reaction, citronella oil

Synthesis and Properties of Ethoxylated Glycerol Monooleate as Palm Oil Based Nonionic Surfactants

Palm oil based nonionic surfactants were synthesized by reacting glycerol monooleate with ethylene oxide at 80 ºC in the prescence of an alkaline catalyst. Purification of the products was conducted by use of acetic acid and black carbon which gave ethoxylated products (EGMO) with a higher level of viscocity and greater solubility in water. Physical and chemical properties of the product such as surface activity, cloud point, acid value, ester value, hydroxyl value, and hydrophilic-lipophilic balance was also determined and results varied depending on the reagent molar ratio. The synthesized EGMO were soluble in water and therefore show potential use as surface active agents in personal care and cosmetic products

CONVERSION OF (±)-CITRONELLAL AND ITS DERIVATIVES TO (-)-MENTHOL USING BIFUNCTIONAL NICKEL ZEOLITE CATALYSTS

(±)-Citronellal and its derivatives were converted to (-)-menthol by a one-pot reaction system using zeolite based nickel catalysts. The catalysts were prepared by immobilization of nickel on natural zeolite (NZ) or synthetic zeolite (ZSM-5) by a simple cation exchange method. Calcination and hydrogen treatment procedures were able to significantly increase the surface area and pore volume of NZ based catalysts whereas negligible changes in the properties were observed for that of ZSM-5. Catalytic reactions were carried out at 70ºC by stirring the mixture in the air for cyclization of (±)-citronellal to (±)-isopulegol followed by hydrogenation towards the desired (-)-menthol at 2 Mpa of H2 pressure. The Ni/NZ catalyst was able to convert a (±)-citronellal derivative yielding 9% (-)-menthol (36% selectivity) with conversion up to 24%, whereas Ni/ZSM5 catalyst directly converted 65% (±)-citronellal to give 4% menthol (6% selectivity). These zeolite based catalysts are therefore potential materials for the conversion of biomass feed stock to value-added chemicals

Aqueous Stability Studies of Polyethylene Glycol and Oleic Acid-Based Anionic Surfactants for Application in Enhanced Oil Recovery through Dynamic Light Scattering

The present study investigates the aqueous stability of polyethylene glycol and oleic acid- based anionic surfactants through the dynamic light scattering (DLS) and zeta potential methods, for application in enhanced oil recovery (EOR). Polyethylene glycol dioleate sulfonate (PDOS) surfactant solutions were prepared in concentrations of 0.05, 0.1, 0.3, 0.5, and 1 wt% in deionized water. Aqueous stability of PDOS was assessed by measuring the droplet size over five days, using nano particle analyzer HORIBA SZ-100 at 25oC. Results show that good aqueous stability of PDOS was achieved at concentrations of 0.1 to 1 wt%, but with the droplet size becoming unstable at the lowest concentration of 0.05 wt%. The polydispersity indices were classified into polydisperse distribution type recorded as 0.3 to 0.5 at concentrations of 0.05 and 0.1 wt% and 0.2 at concentrations of 0.3 to 1 wt%. The critical micelle concentration (CMC) of PDOS was 0.3% and the interfacial tension of PDOS surfactant above the CMC was around 10-3 dyn/cm. The zeta potential of PDOS surfactant without the addition of salt in concentrations of 0.05, 0.1, 0.3, 0.5, and 1 wt% was highly stable up to -96.8, -90.5, -89.6, -82.3, and -64.4 mV, respectively. With the addition of salt they were moderately stable at a concentration of 1 wt%. The conductivity increased with increasing concentration. The zeta potential of PDOS with the addition of salt was moderately stable in a concentration of 1%. Although PDOS with concentration of 0.05% showed a high value of zeta potential with the addition of salt, there is no guarantee that the PDOS surfactant solution will be stable for five days