GLASNIK HEMIČARA, TEHNOLOGA I EKOLOGA REPUBLIKE SRPSKE
Adsorption, as an easy and effective technique, is widely used to remove a large number of dyes f... more Adsorption, as an easy and effective technique, is widely used to remove a large number of dyes from aqueous solutions. Activated carbon is the most desirable adsorbent, but due to its high cost, its use is limited. Proving the possibility of adsorption and its efficiency performed on cheap adsorbents is a great challenge and interest of many researchers in the past few decades. In this paper, unmodified (P) and modified sawdust obtained in two ways (HCl treatment and NaOH treatment), labeled as PHCl and PNaOH, are used for the removal of the methylene blue dye. Adsorption experiments showed that the optimal time for adsorption is different, for the sample PNaOH – 30 min, for the sample P – 45 min, and for the sample PHCl – 60 min. By applying nonlinear kinetic models to the experimentally obtained data, it was found that the best model that describes this adsorption is pseudo-second-order model. By examining the effect of pH values on adsorption, different results were obtained (fo...
Slideway oils have application in many industries, such as automotive, food, beverage, packaging,... more Slideway oils have application in many industries, such as automotive, food, beverage, packaging, and considerable amount is used in small machinery workshops. Market analyses have shown that most common viscosity grade is ISO VG 68, followed by ISO VG 220. Because water soluble metal working fluids come in contact with slideway oils, purpose of this research was to test the influence of water soluble fluids on most commonly used viscocity grades of slideway oils. Compatibility of slideway oils with water soluble metal working fluids is very important for effective funcioning of slideway machines, and for life span of slideway oil itself. Compatibility was tested with specially adjusted demulsivity tests, regarding the capability of separating specific amount of water soluble metal working flud from slideway oil. Different formulations of cooling and lubricating fluid and slideway oil give different times and ratios of separated oil and water on modified test. Test results can be us...
Mineral base oils are extracted from oil fractions of naphta that has boiling point of over 350 °... more Mineral base oils are extracted from oil fractions of naphta that has boiling point of over 350 °C, and contain different kinds of carbohydrates and hetero-compunds. Removal of unwanted compunds from mineral base oils in domestic rafineries is made by rafination of imported commercial clays. For ther eventual replacement there has been conducted a testing of various domestic adsorbens. In this paper, examples of natural alumina from the vicinity of Sipovo are previously activated with sulphuric acid, and then used for rafination of naphtenic and hydrocracked base oil in laboratory conditions. Emerged changes on mineral base oils are followed by corresponding standardised methods. Results of testing showed that, by refining the given base oils with activated alumina, one can achieve good results and therefore further explorations shoud be continued, because of their commercial application in semi-industry and industry conditions
JOURNAL OF ENGINEERING & PROCESSING MANAGEMENT
Ulja za klizne staze primjenjuju se u mnogim granama industrije, kao što je industrija automobila... more Ulja za klizne staze primjenjuju se u mnogim granama industrije, kao što je industrija automobila, hrane, pića, ambalaže, a značajne količine troše se i u malim mašinskim radionicama. Analize tržišta pokazale su da je najzastupljenija viskozna gradacija ISO VG 68, zatim slijedi ISO VG 220. S obzirom da vodorastvorna sredstva za obradu metala dolaze u kontakt sa uljem za klizne staze, cilj istraživanja je ispitivanje uticaja vodorastvornih sredstava na najčešće korišćene viskozitetne gradacije ulja za klizne staze. Kompatibilnost ulja za klizne staze i vodorastvornih sredstava je veoma važna za efektivno funkcionisanje mašina sa kliznim stazama i za radni vijek samog ulja za klizne staze. Kompatibilnost je određivana posebno prilagođenim testovima deemulgivnosti, odnosno sposobnosti odvajanja određene količine vodorastvornog sredstva za obradu metala od ulja za klizne staze. Različite formulacije sredstava za hlađenje i podmazivanje i ulja za klizne staze daju i različita vremena i o...
The introduction of different additives into the cooling and lubrication systems in the metal cut... more The introduction of different additives into the cooling and lubrication systems in the metal cutting process, contributed to improving the machining process sustainability. Different types of additives can help to reduce friction, reduce wear of contact surfaces, improve heat dissipation from the cutting zone, etc. With the development of nanotechnology, great focus has been placed on the investigation and using of nano-particles, nano-additives and nanofluids in industry. In this paper, the effects of using the nano-particle based cooling and lubrication fluid are investigated. There are performed comparison effects of standard cooling and lubrication fluids versus nanofluids based cooling and lubrication on cutting process performance. Molybdenum disulphide particles are used as nano-particles, which dispersed in a standard cooling and lubrication fluid. As workpiece was used alloyed tool steel. Milling process performance indicators was analysed based on Taguchi experimental plan, for different cooling and lubrication condition and process parameters. Cutting forces component in three perpendicular axes, and machined surface parameters were measured. Experimental analysis has shown that the use of nano-particles, which mixed in a standard cooling and lubrication fluid, significantly contributes to the reduction of cutting forces, friction coefficients, more efficient cutting and generation of machined surfaces.
GLASNIK HEMIČARA, TEHNOLOGA I EKOLOGA REPUBLIKE SRPSKE
Adsorption, as an easy and effective technique, is widely used to remove a large number of dyes f... more Adsorption, as an easy and effective technique, is widely used to remove a large number of dyes from aqueous solutions. Activated carbon is the most desirable adsorbent, but due to its high cost, its use is limited. Proving the possibility of adsorption and its efficiency performed on cheap adsorbents is a great challenge and interest of many researchers in the past few decades. In this paper, unmodified (P) and modified sawdust obtained in two ways (HCl treatment and NaOH treatment), labeled as PHCl and PNaOH, are used for the removal of the methylene blue dye. Adsorption experiments showed that the optimal time for adsorption is different, for the sample PNaOH – 30 min, for the sample P – 45 min, and for the sample PHCl – 60 min. By applying nonlinear kinetic models to the experimentally obtained data, it was found that the best model that describes this adsorption is pseudo-second-order model. By examining the effect of pH values on adsorption, different results were obtained (fo...
Slideway oils have application in many industries, such as automotive, food, beverage, packaging,... more Slideway oils have application in many industries, such as automotive, food, beverage, packaging, and considerable amount is used in small machinery workshops. Market analyses have shown that most common viscosity grade is ISO VG 68, followed by ISO VG 220. Because water soluble metal working fluids come in contact with slideway oils, purpose of this research was to test the influence of water soluble fluids on most commonly used viscocity grades of slideway oils. Compatibility of slideway oils with water soluble metal working fluids is very important for effective funcioning of slideway machines, and for life span of slideway oil itself. Compatibility was tested with specially adjusted demulsivity tests, regarding the capability of separating specific amount of water soluble metal working flud from slideway oil. Different formulations of cooling and lubricating fluid and slideway oil give different times and ratios of separated oil and water on modified test. Test results can be us...
Mineral base oils are extracted from oil fractions of naphta that has boiling point of over 350 °... more Mineral base oils are extracted from oil fractions of naphta that has boiling point of over 350 °C, and contain different kinds of carbohydrates and hetero-compunds. Removal of unwanted compunds from mineral base oils in domestic rafineries is made by rafination of imported commercial clays. For ther eventual replacement there has been conducted a testing of various domestic adsorbens. In this paper, examples of natural alumina from the vicinity of Sipovo are previously activated with sulphuric acid, and then used for rafination of naphtenic and hydrocracked base oil in laboratory conditions. Emerged changes on mineral base oils are followed by corresponding standardised methods. Results of testing showed that, by refining the given base oils with activated alumina, one can achieve good results and therefore further explorations shoud be continued, because of their commercial application in semi-industry and industry conditions
JOURNAL OF ENGINEERING & PROCESSING MANAGEMENT
Ulja za klizne staze primjenjuju se u mnogim granama industrije, kao što je industrija automobila... more Ulja za klizne staze primjenjuju se u mnogim granama industrije, kao što je industrija automobila, hrane, pića, ambalaže, a značajne količine troše se i u malim mašinskim radionicama. Analize tržišta pokazale su da je najzastupljenija viskozna gradacija ISO VG 68, zatim slijedi ISO VG 220. S obzirom da vodorastvorna sredstva za obradu metala dolaze u kontakt sa uljem za klizne staze, cilj istraživanja je ispitivanje uticaja vodorastvornih sredstava na najčešće korišćene viskozitetne gradacije ulja za klizne staze. Kompatibilnost ulja za klizne staze i vodorastvornih sredstava je veoma važna za efektivno funkcionisanje mašina sa kliznim stazama i za radni vijek samog ulja za klizne staze. Kompatibilnost je određivana posebno prilagođenim testovima deemulgivnosti, odnosno sposobnosti odvajanja određene količine vodorastvornog sredstva za obradu metala od ulja za klizne staze. Različite formulacije sredstava za hlađenje i podmazivanje i ulja za klizne staze daju i različita vremena i o...
The introduction of different additives into the cooling and lubrication systems in the metal cut... more The introduction of different additives into the cooling and lubrication systems in the metal cutting process, contributed to improving the machining process sustainability. Different types of additives can help to reduce friction, reduce wear of contact surfaces, improve heat dissipation from the cutting zone, etc. With the development of nanotechnology, great focus has been placed on the investigation and using of nano-particles, nano-additives and nanofluids in industry. In this paper, the effects of using the nano-particle based cooling and lubrication fluid are investigated. There are performed comparison effects of standard cooling and lubrication fluids versus nanofluids based cooling and lubrication on cutting process performance. Molybdenum disulphide particles are used as nano-particles, which dispersed in a standard cooling and lubrication fluid. As workpiece was used alloyed tool steel. Milling process performance indicators was analysed based on Taguchi experimental plan, for different cooling and lubrication condition and process parameters. Cutting forces component in three perpendicular axes, and machined surface parameters were measured. Experimental analysis has shown that the use of nano-particles, which mixed in a standard cooling and lubrication fluid, significantly contributes to the reduction of cutting forces, friction coefficients, more efficient cutting and generation of machined surfaces.
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