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Abstrak :
Pelarut organik umumnya digunakan oleh laboratorium kimia untuk keperluan analisis sampel dan merupakan salah satu bahaya kimia yang potensial yang dapat memajani pekerja di laboratorium itu. Dalam penelitian ini dilakukan penilaian risiko terhadap uap pelarut organik di suatu laboratorium pelumas berupa toluena, xilena, heksana, dan klorobenzen. Penilaian risiko masing – masing uap plearut tersebut diakukan berdasarkan penilaian tingkat bahaya, tingkat pajanan, dan tingkat risiko beserta kondisi pengendalian yang telah ada sehingga dapat diketahui karakterisasi risikonya. Salah satu langkah untuk mendapatkan data – data tersebut adalah dengan mengetahui besaran pajanan uap pelarut organik terhadap sample pekerja. Hasil analisis menunjukkan bahwa konsentrasi uap pelarut toluena, xilena, heksana, dan klorobenzena yang memajani sampel pekerja masih berada dibawah nilai ambang batas yang direkomendasikan oleh American Confrence of Governmental Industrial Hygienist (ACGIH). Karakteristik risiko pajanan uap pelarut organik toluena dan heksana terhadap seluruh sampel pekerja laboratorium pelumas PT. PS adalah C3; Karakteristik risiko pajanan uap pelarut organik xilena terhadap analis sedimen, analis visco, dan helper laboratorium pelumas PT. PS adalah C3, sedangkan terhadap analis destilasi, flash point, FTIR, PQ Index, TAN, TBN, interpreter, reporting 1 dan reporting 2 berada pada risiko C1; Karakteristik risiko pajanan uap pelarut organik klorobenzena terhadap analis TBN, dan helper laboratorium pelumas PT. PS adalah C3, sedangkan analis destilasi, flash point, FTIR, PQ Index, TAN, visco, interpreter, reporting 1 dan reporting 2 berada pada risiko C1 ......Generally Organic solvent is used by chemical laboratory for sample analysis needed and it is become one of potential chemical hazardous that can expose to laboratory worker. This research is doing risk assessment of organic vapor at lubricant laboratory, ie toluene, xilene, hexane, and chlorobenzene. Risk assessment of those organic vapors is based on hazard rating, exposure rating, risk rating, and observation about mitigation in order to know its risk characterization. One of the steps to know the exposure rating data is knowing magnitude rating of organic vapor which is expose to laboratory worker. The result shows that concentration of toluene, xilene, hexane, and chlorobenzene is still below threshold limit value recommended American Conference of Governmental Industrial Hygienist (ACGIH). Risk characrterization of toluene and hexane exposure to laboratory worker is C3; Risk characrterization of xylene exposure to sediment and visco analyst also helper is C3 while to destilation, flash point, FTIR, PQ Index, TAN, TBN analyst, interpreter, reporting 1 and reporting 2 is C1; Risk characrterization of chlorobenzene exposure to TBN analyst and helper is C3 while to destilation, flash point, FTIR, PQ Index, TAN, sedimen, visco analyst, interpreter, reporting 1 and reporting 2 is C1

Abstrak :
Film bionanokomposit kitosan/Na-MMT/glutaraldehid (GLA) telah berhasil disintesis dengan metode solvent casting. Selain itu, uji aktivitas antimikroba dengan bakteri S. aureus dan Salmonella juga telah dilakukan. Terdapat tiga tahapan dalam melakukan sintesis. Tahapan pertama adalah Sintesis serbuk Bionanokompoit dengan metode presipitasi lalu tahapan selanjutnya serbuk bionanokomposit digunakan untuk pembuatan Film berbasis kitosan sehingga terbentuk Film Bionanokomposit Na-MMT/Kitosan/GLA. Selain itu juga dilakukan variasi penambahan material pada permbuatan serbuk bionanokomposit yaitu penambahan kitosan (0,5; 1; 2; 3 ;4 gram), variasi penambahan Na-MMT (0,5; 1; 2; 3 ;4 gram) terhadap 10 mL GLA dan variasi Na-MMT berbanding kitosan terhadap GLA masing-masing yaitu; (0,5:2,5); (1:2); (1,5:1,5); (2:1); (2,5:0,5) gram. Karakterisasi yang dilakukan berupa FTIR, XRD, TEM, uji kelarutan dalam air dan uji aktivitas antibakteri. Karakterisasi FTIR memberikan indikasi interaksi GLA dengan kitosan ditunjukkan adanya puncak pada bilangan gelombang 1613 cm-1 dan interaksi Kitosan dengan Na-MMT oleh munculnya regangan (C=N) pada bilang gelombang 1613 cm-1. Selain itu, karakterisasi XRD pada serbuk bionanokomposit menunjukkan pergeseran nilai basal spacing pada Na-MMT. Hal ini mengindikasikan bahwa GLA telah berhasil melakukan interkalasi terhadap Na-MMT dan menjadikan sifat hidrofilik dari Na-MMT menjadi organofilik. Sebagai pendukung data pada karakterisasi XRD, karakterisasi TEM memperlihatkan layer Na-MMT yang telah terinterkalasi. Uji kelarutan dalam air yang telah dilakukan memperlihatkan penyusutan bionanokomposit terkecil sebesar 9,19 % dari berat semula yaitu kitosan film dengan persen kelarutan dalam air yaitu sebesar 23,44%. Selain itu, uji aktivitas antibakteri memberikan nilai zona hambat paling besar yaitu 15,5 mm pada bakteri Salmonellla sp dan 8,5 mm pada bakteri S aureus setelah inkubasi 48 jam. ......In this study, the solvent casting method was used to successfully produce a chitosan/Na-MMT/glutaraldehyde (GLA) bionanocomposite film. Antimicrobial activity studies also performed. The microorganisms Staphylococcus aureus and Salmonella were also tested. In the synthesis, there are three steps. The initial stage is to make bionanocomposite powder using the precipitation method, followed by bionanocomposite preparation. Then the next step is the bionanocomposite powder used to manufacture chitosan-based films to form a Na-MMT/chitosan/GLA bionanocomposite film. In addition, variations in the addition of materials to the manufacture of bionanocomposite powders were carried out, namely the addition of chitosan (0.5; 1; 2; 3 ;4 grams), variations in the addition of Na-MMT (0.5; 1; 2; 3 ;4 grams) to 10 mL of GLA and variation of Na-MMT versus chitosan to GLA, respectively; (0,5:2,5); (1:2); (1,5:1,5); (2:1); (2.5:0.5) grams. Characterization carried out in the form of FTIR, XRD, TEM, water solubility test and antibacterial activity test. The FTIR characterization gave an indication of the interaction of GLA with chitosan indicated by the peak at wave number 1613 cm-1 and the interaction of Chitosan with Na-MMT by the appearance of streching (C=N) at wave number 1613 cm-1. In addition, the XRD characterization of the bionanocomposite powder showed a shift in the basal spacing value of Na-MMT. This indicates that GLA has successfully intercalated Na-MMT and made the hydrophilic nature of Na-MMT organophilic. To support the data on XRD characterization, TEM characterization shows the intercalated Na-MMT layer. The water solubility test that has been carried out shows the smallest shrinkage of the bionanocomposite of 9.19% from its initial weight, namely chitosan film with a percent solubility in water of 23.44%. In addition, the antibacterial activity test gave the greatest inhibition zone value, namely 15.5 mm for Salmonella sp and 8.5 mm for S aureus after 48 hours of incubation.

Abstrak :
This research considers the application of Natural Deep Eutectic Solvents (NADES) as green solvents for the extraction of bioactive compounds, mainly ?-mangostin, from the pericarp of mangosteen (Garcinia mangostana L.). Extractions were carried out using NADES consisting of choline chloride, a quarternary ammonium salt, and four hydrogen bond donors: 1,2-propanediol, citric acid, glycerol, and glucose. The highest ?-mangostin extraction yield of 2.6 % (w/w) in dried pericarp was obtained using a mixture of choline chloride and 1,2-propanediol in 1:3 mole ratio. The presence of hydrogen bonding was indicated by the broadening of the OH peak in the infra-red spectra of the NADES used. The polarity and viscosity data of NADES were determined to describe the solubility of a-mangostin. The decomposition and glass transition temperatures were determined in order to study their thermal behavior and stability. The results of this study suggest that NADES made of choline chloride and diol-based hydrogen bond donors are effective for the extraction of bioactive compounds from the mangosteen pericarp.

Abstrak :
Green solvents volume I and II provides a throughout overview of the different types of solvents and discusses their extensive applications in fields such as extraction, organic synthesis, biocatalytic processes, production of fine chemicals, removal of hydrogen sulphide, biochemical transformations, composite material, energy storage devices and polymers.

Abstrak :
Volatile organic solvents are the normal media used in both research scale and industrial scale synthesis of organic chemicals. Their environmental impact is significant, however, and so the development of alternative reaction media has become of great interest. Developments in the use of water as a solvent for organic synthesis have reached the point where it could now be considered a viable solvent for many organic reactions. Organic Reactions in Water demonstrates the underlying principles of using water as a reaction solvent and, by reference to a range of reaction types and systems, it's effective use in synthetic organic chemistry. This book with a strong focus on the practical use of water as a reaction medium, this book illustrates the enormous potential of water for the development of new and unique chemistries and synthetic strategies, while at the same time offering a much reduced environmental impact.