Judul: Kajian Pirolisis Batang dan Daun Jagung Untuk Bahan Tambahan Makanan
Abstrak: The development in agricultural activity will produce an overflow of the waste. In the future, it will cause an environment issue thus it need a convertion technology to modify the waste useful product. Corn, for example, is one of agricultural plants which produces much waste such as leaf, husk, cob, stalk, stover, etc. These by product, off course, will be valuable if it could be used for food, feed or others. The purpose of this research was to investigate the effect of temperature and catalyst percentage toward pyrolysis of corn stalk and leaves. Furthermore, the research was to know the contents liquid resulting form the pyrolysis of the corn leaves and stalk material whether it can be use for food additive. The best treatment was fixed by yield and the content of pyrolysis liquid. The first stage of this research was to determine the temperature of the operational pyrolysis using TGA. The process of the pyrolysis was conducted in the temperature range of 150-650ºC. There are two kind of process, with 1,5% catalyst and without catalyst. Furthermore, the amount of component which contained in liquid resulted from the pyrolysis was determined by using GC-MS. The last stage, it determined group and function from the components containing in that liquid. The best result was achieved at temperature of 350ºC, without catalyst and produced 17,035 g of liquid and 37,18 g of char. So far the pyrolysis without catalyst produced more liquid and char but less gass. In the meanwhile addition of 1,5% catalyst increased the amount of gass and decreased of liquid and char. GCMS identifed the component in the liquid as its group and function. Liquid resulted from the pyrolysis without catalyst contained more fenol group while the process with catalyst had more acid and fenol group. From the GC-MS analysist, it was comfirmed that the pirolysis without catalyst at temperature of 350ºC produced more components wich functioned as food additive, i.e. : p-cresol, pyrocatechol, vanillin, palmitic acid, and syringaldehide.
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Judul: Kajian Optimasi Proses Pirolisis Tongkol Jagung untuk Produksi Asap Cair
Abstrak: Corn is usually used as food, feed, and also raw materials for industries. The increasing of annual corn consumption’s impact on the increasing of its biomass, especially the corn cobs. These corn cobs, as raw materials, are still not used optimally yet. Corn cobs can be used as main raw materials for smoke liquid through pyrolysis. But, optimal temperature condition and catalyst concentration added are still unknown to create maximal liquids. The aim of this research is to understand the influence of temperature and catalyst concentration in pyrolysis process to its yield. Getting its surface response from factors of temperature and catalyst concentration and its optimum condition of pyrolysis process become the other objective of this research. Setting up the temperature and catalyst added treatment is based on Response Surface Methods (RSM). Center point is set based on previous research done by Choiriyah (2010). Temperature that used is of 4500C-6500C (-1, +1 point) and atapulgit that added is 1-2% (-1, +1 point). The result then be analyzed by SAS 9.1 to get optimal yield treatment. The liquid components are identified by GC MS and the raw material decomposition are fixed by fiber and silica proportion test. Optimum result is shown on center point, 10.01, that 22. 225 gram liquids and 32.93 gram ashes are resulted on 5500C and 1.5% catalyst added. As high the temperature, as low ashes would be resulted, as high the weigh loss value, and as low lignocelluloses value. Silica value increase together with catalyst adding. GC MS analysis shows the component of aldehydes, phenol, ketones, hydrocarbon, and furan as the result. That compounds can be used as food additives, such as preservatives, antioxidant, and flavor. The most component variation set on 5500C with the adding of 0.79% catalyst, which resulted in phenol, aldehydes, acids, alcohols, ketones, and hydrocarbons.
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Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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