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On the Interactions of Additives in Metalworking Fluids with Metal Surfaces  [PDF]
Joachim Schulz,Ekkard Brinksmeier,Daniel Meyer
Lubricants , 2013, DOI: 10.3390/lubricants1040075
Abstract: Metalworking fluids (MWF) play a significant role in manufacturing processes, such as machining or forming. Consequently, a high number of MWF with varying chemical composition are commercially available. However, the working mechanisms of the MWF are still object of discussion in science and application. This paper addresses the possible interactions of additives with metal surfaces taking the characteristic conditions in machining and forming processes as well as the chemical properties of the surface and the additives into account. The new model for possible interaction of additives with the metal surface is considered and supported by experimental data. This new model does not imply reaction layers as tribological active layer anymore.
Enhanced DLC wear performance by the presence of lubricant additives
Costa, Romina Paula de Castro;Marcian, Fernanda Roberta;Oliveira, Deiler Ant?nio Lima;Trava-Airoldi, Vladimir Jesus;
Materials Research , 2011, DOI: 10.1590/S1516-14392011005000023
Abstract: lubricant additives play significant role for reducing friction and wear of mechanical elements. the additives presented in 5w30 oil were developed for metal surfaces. however, they have been used in engine pieces covered with dlc coatings because they also offer the potential to reduce friction losses and wear in automotive applications. the friction and wear tests were carried out by using a umt-cetr ball-on-disk tribometer in rotational mode under 5w30 synthetic oil at 100 °c. the x-ray photoelectron spectroscopy (xps) showed the presence of mo and s in the wear tracks. these elements are from decomposition of zddp and modtc additives producing mos2 in dlc surface, which offers enhanced durability by low wear rate.
Optimization of control parameters for petroleum waste composting
MA Ying,WONG Ming-Hung,ZHANG Jia-yao,WU Wen-zhong,
MA Ying
,WONG Ming-Hung,ZHANG Jia-yao,WU Wen-zhong

环境科学学报(英文版) , 2001,
Abstract: Composting is being widely employed in the treatment of petroleum waste. The purpose of this study was to find the optimum control parameters for petroleum waste in-vessel composting. Various physical and chemical parameters were monitored to evaluate their influence on the microbial communities present in composting. The CO2 evolution and the number of microorganisms were measured as the activity of composting. The results demonstrated that the optimum temperature, pH and moisture content were 56.5-59.5 degrees C, 7.0-8.5 and 55%-60%, respectively. Under the optimum conditions, the removal efficiency of petroleum hydrocarbon reached 83.29% after 30 days composting.
Evaluation of Additives as Corrosion Inhibitors/Antioxidants for High Quality Nano Emulsifiable Oils of Metalworking Fluids  [PDF]
Noura El Mehbad
Journal of Surface Engineered Materials and Advanced Technology (JSEMAT) , 2014, DOI: 10.4236/jsemat.2014.43019
Abstract:


Surfactants used for formulation metal working fluids. In the present paper, the inhibitive effect of synthesized anionic surfactant P-decyloxy p-sodium sulphonateazobenzene with chemical structure H21C10O-Ph-N=N-Ph-SO3Na and 1-ethyl-1-dodecyl-2-sulphonate-4-(hydroxyl ethyl)-piprazine on the corrosion of carbon steel in sulphuric acid solution is measured by the weight loss method. The relationships between the concentrations of these inhibitors and their surface properties, thermodynamic properties, surface coverage and inhibiting efficiency, have been investigated. The results indicate that P-decyloxy p-sodium sulphonate azobenzene is superior to 1-ethyl-1-dodecyl-2-sulphonate-4-(hydroxyl ethyl)-piprazine at high acid concentration. These inhibitors blend with coupling agent to produce water miscible cutting fluid. Values of surface tension of these additives were measured in water phase and consequently CMC was determined for all inhibitors. The efficiency of these inhibitors depends on their chemical structure and the presence of hydrophilic group to association of the surfactant with metal surface, hence very good wetting properties. The anti-corrosion characteristic of surfactants increases with increasing polar linkages in the aromatic moieties forming chelated and coordinated layer. This is due to the increase in number of sites to chemisorption on the metal surface. These studies have led to much clear evidence of the intimate relationship between the chemical structure of the surfactants and their efficiency. More confirmation for suggested mechanism was investigated by measuring the area occupied per molecule of the surfactant at aqueous phase. The results indicate that the amphoteric surfactant more efficient than anionic surfactant. The antioxidants activities of different dosages of inhibitors were evaluated and suggested mechanism according to their thermodynamics parameters. The oxidation of the oil has been carried for different time intervals. The degradation of the oil has been monitored by

Clarification and filtration of the floculated partuicles suspension from a chemical treatment of waste oil-in-water emulsions from a non-ferrous metalworking plant  [PDF]
Lazarevi? Vesna B.,Krsti? Ivan M.,Taki? Ljiljana M.,Lazi? Miodrag L.
Hemijska Industrija , 2011, DOI: 10.2298/hemind100801054l
Abstract: The effects of the coagulation/floculation conditions on clarification and filtration of the floculated particle suspension obtained by the chemical treatment of the waste oil-in-water emulsion (OWE) from a non-ferrous metalworking plant were studied. The treatment involved the addition of aluminum(III) sulfate and lime to the OWE. The main goal was to define the optimum conditions for clarification and filtration of the floculated particle suspension. The factors involved were amounts lime (i.e. pH) and filter aid added the OWE on clarification and filtration rates. At pH>10, the clarification rate was increased and the final volume of the concentrated suspension (sludge) was reduced, while filter aid affected negatively the clarification rate. The filtration rate was also increased when the coagulation was carried out at pH>10. The floculated particle suspension should be concentrated before filtration in order to decrease the filtration duration. The most efficient filter aid was Celite standard super-cel, its optimum initial concentration being found to be 2 g/dm3.
POLYMER ADDITIVES EFFECT ON THE DYNAMIC VISCOSITY OF BITUMINOUS MATRICES USED FOR RADIOACTIVE WASTE FIXATION  [PDF]
Michaela Svitoková,Pavol Dau?ík
Petroleum and Coal , 2010,
Abstract: One way of fixation of radioactive waste is bitumination. In this process a certain quantity ofradioactive waste (ion exchangers, slurry, concentrate) is fixed in to the heated bitumen.Solidification of radioactive wastes in bitumen matrix significantly affects the viscosity. To improvethe viscosity properties of bitumen matrix are used polymer modifiers additives. The articlepresents the results of monitoring the impact of the concentration of polymer additives on thedynamic viscosity of the bitumen matrix at temperatures of 80° C to 150° C.
Investigation of Peculiarities in the Hardening Process of Portland Cements with Active Additives out of Waste
Jadvyga ?VIRONAIT?,Ina PUNDIEN?,Valentin ANTONOVI?,Valdas BALKEVI?IUS
Materials Science , 2011, DOI: 10.5755/j01.ms.17.1.254
Abstract: This study deals with the impact of waste fluid cracking catalyst (FCC) and cupola dust (CD) on hardening process of various Portland cements (CEM I 42.5 R (PCR), CEM I 42.5 N (PCN), CEM II/A-S 42.5 N (PCSN)). The plain cement pastes and waste modified pastes (with cements replacement for 10 % of additives), also pastes with the well-known pozzolana additive, microsilica (MS), were investigated. The studies of development of hardening structure by ultrasound wave velocity (UWV) measurement method, of change of mineral composition and physical-mechanical properties were carried out. Impact of additives is subject to both the own properties (chemical, mineral composition and fineness) of additive and of cement. FCC accelerates noticeably the development of initial structure of finer cement (PCR) only. Beyond 24 h development of structure in all FCC modified pastes is going somewhat slower, nevertheless, after 28 days their structure is already more compact than that of plain pastes. The strength properties are changing accordingly. The development of initial structure of CD modified PCR, and especially PCSN, pastes is going faster, PCN - almost does not change. Beyond 24 h compacting of structure of all CD modified pastes was slower. For the early strength of cements, the impact of CD was negligible, after 28 and 90 days the strength of CD modified PCR and PCN pastes was lower than that of plain pastes. In the case of PCSN, the slag is activated by alkali and the strength increased. CD additive, like MS and FCC, decreases the OH" concentration in the liquid phase of hydrating cement suspensions at the initial period (till 3 h), however further in the course of 28 days it was growing and became higher than that of plain cement suspensions. http://dx.doi.org/10.5755/j01.ms.17.1.254
HARMONIZATION OF CROATIAN LEGAL REGULATIONS WITH EU DIRECTIVES CONCERNING PETROLEUM INDUSTRY WASTE DISPOSAL INTO SUITABLE GEOLOGICAL FORMATIONS
Vladislav Brki?,Daria Karasalihovi? Sedlar
Rudarsko-Geolo?ko-Naftni Zbornik , 2010,
Abstract: Exploration and production of mineral resources, especially hydrocarbons, are from ecological point of view, one of the most sensitive activities. Concerning global ecological standards, which have also been enforced into petroleum industry, exploration and production of mineral energy sources have to be based on compliance with introduced environmental and human health protection requirements. Since it is expected that Croatia will join European Union in the near future, it is necessary to develop institutional and legislative frameworks for enabling and regulating the harmonization of mineral resources exploration and production waste disposal with European Union directives and regulations. Petroleum industry waste disposal by injection into suitable geological formations is one of environmentally acceptable methods for petroleum industry waste management.
Cobalt Recovery from Waste Catalysts (Petroleum Refining Industry from Gujarat)  [PDF]
Palanivel Sivasakthi, Natarajan Sathaiyan
Open Journal of Metal (OJMetal) , 2012, DOI: 10.4236/ojmetal.2012.21004
Abstract: A hydrometallurgical process has been developed for cobalt recovery from a waste catalyst (petroleum refining industry). This waste catalyst containing about 2.18 weight % of Co, is highly contaminated by Mg, Al, Si, Ca, Fe, Ni, Cu, Zn, Mo. The major steps are: (I) The spent catalyst is roasted with flux material in an electrical furnace at very high temperature (700?C) for a specific duration. (II) The roasted sample is leached with sulphuric acid to bring the metal contents into solution form. (III) For separating cobalt values from the leach solution, the solution pH is raised by NaOH addition, where all cobalt content is precipitated at a pH of about 12. (IV) This cobalt hydroxide precipitate is filtered and dissolved in minimum amount of sulphuric acid to get cobalt sulphate solution which is used as the electrolyte for the electrolytic recovery of cobalt. For optimizing various parameters like (1) H2SO4 concentration; (2) Duration; (3) Cobalt concentration; (4) Current density; (5) Temperature; (6) Stirring etc., The particle surface morphology and deposited layers have been characterized by scanning electron microscopy (SEM). A compact metallic deposit containing 70% cobalt was obtained.
DEGRADATION OF PETROLEUM REFINERY WASTE BY A CONSORTIUM OF HYDROCARBONOCLASTIC BACTERIA ON SEVERAL C:N:P RATIO  [cached]
Syukria I Zam,Irfan Mustafa
Journal of Tropical Life Science , 2012,
Abstract: Bioremediation is an alternative method to treat petroleum waste using microorganism into nontoxic end product. The method is relatively cheap, effective, and environmental friendly. A key factor influencing bioremediation process for petroleum refinery waste treatment is C:N:P ratio of bacterial growth medium. The objective of this research was to obtain C:N:P ratio of Stone Mineral Salt Solution (SMSS) medium that allow optimal degradation of petroleum refinery waste by consortium of hydrocarbonoclastic bacteria. C:N:P ratio of SMSS medium was adjusted to ratio of 100:10:1, 100:10:0.5, 100:5:1, and 100:5:0.5. We demonstrate that optimal degradation of petroleum refinery waste by a consortium of hydrocarbonoclastic bacteria was achieved in SMSS medium with C:N:P ratio of 100:5:1. It allowed 66.55% degradation of total petroleum hydrocarbon (TPH) and 85.18 % decrease of chemical oxygen demand (COD) value.
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