RESEARCH OF COMPOSITION OF ANTIWEAR ADDITIVES FOR JET FUELS

In the framework of the state import substitution program for the development of a domestic antiwear additive for jet fuels the physicochemical characteristics of the approved foreign antiwear additives of DNK, HITEC 580 and Unicor J were analyzed at the first stage. The analysis revealed that using solvents during the production of HITEC 580 additives and Unicor J improve their consumer properties (low temperature characteristics). At the second stage of the study the composition of currently used additives HITEC 580 and Unicor J was studied by gas chromatography-mass spectrometry. It was shown, that the same active component is used in their composition - dimers of unsaturated fatty acids C18, namely a mixture of dimers of linolenic, linoleic and oleic acids, among which the dimer formed from linoleic and oleic acids prevails. An analysis of the solvents used in the additive composition showed that in the production of Unicor J additives they use an aromatic solvent containing 92% of monoaromatic compounds, mainly of the C10 series, which is probably the product of gasoline reforming, and HITEC 580 additives use an aliphatic solvent containing mainly n alkanes (41%). From the presented results of the study it follows that when developing a domestic antiwear additive formulation, it is necessary to choose compounds containing 1 or 2 carboxyl groups as the active component, and as the solvent either aromatic or aliphatic, depending on the cost and availability on the domestic market.

Avocado oil mixed with an antiwear additive as a potential lubricant – Measurement of antiwear and extreme pressure properties

The paper aims to study the antiwear (AW) and extreme pressure (EP) properties of avocado oil mixed with zinc dialkyl dithiophosphate (ZDDP) in concentrations of 1% to 3% by weight for lubrication purposes. The AW and EP tests are conducted as per ASTM-4172 and ASTM-2783 standards respectively. Further, the rheological behavior of avocado oil mixed with ZDDP is determined for varying shear rates of 50 – 2000 s−1. The maximum improvement in the wear properties for avocado oil is equal to 39.8% at 1 wt.%. The load wear index of pure avocado oil increases from 32.6 to 80.3 at 3 wt.% ZDDP whereas, the weld point increases to 252 kgf at 3 wt.% ZDDP. The improvement in the antiwear and extreme pressure properties are attributed to the protective film formation on the tribopairs as characterized by SEM and EDX analysis. Also, the addition of ZDDP increases the viscosity of the oil at all concentrations and maintains the Newtonian behavior of oil.

Tribochemical Interactions between Carbon Nanotubes and ZDDP Antiwear Additive during Tribofilm Formation on Uncoated and DLC-Coated Steel

The data from the authors’ earlier investigations show that molecules of zinc dithiophosphate (ZDDP) added to a lubricant can absorb energy emitted by a solid surface, which is where triboreactions occur. If the lubricant contains structures able to conduct energy, the ZDDP reactions can occur even at a relatively large distance from the solid surface, which should increase the effectiveness of ZDDP as an antiwear additive. The purpose of this paper was to verify the thesis that the tribocatalytic effect depends on the ability of the solid surface to emit electrons/energy and the ability of ordered molecular structures, such as carbon nanotubes (CNTs), to conduct energy and, most likely, to enhance the energy transfer. The tribological tests were performed using a TRB3 tribotester for 100Cr6 steel balls and uncoated or a-C:H coated HS6-5-2C steel discs. Polyalphaolefin 8 (PAO8) and PAO8 mixed with ZDDP and CNTs were used as lubricants. The results of the tribological tests suggested that: (a) the effect of the interactions between ZDDP and CNTs was clearly visible; (b) the structure and properties of the solid surface layer had a significant influence on the antiwear action of the ZDDP additive.

Comparison of tribological performances of sulfur based and boron succuminide containing antiwear additive with ZDDP by engine bench tests

Purpose This study aims to evaluate and compare by 100 hours engine bench tests the tribological performances of two types of lubrication oils, which were sulfur-based, boron succinimide-containing antiwear package (NP-3) oil and conventional zinc dialkyldithiophosphate (ZDDP)-containing (R-1) oil. Design/methodology/approach The tribological performances of the oils were evaluated in three main contexts, including engine tests, physical/chemical changes and surface analysis. Findings Results showed that NP-3 lubrication oil, which was environment- and catalyst-friendly, can be an alternative lubrication oil with its tribological performance due to similar antiwear characteristics with the ZDDP. Originality/value Attempts to develop catalysis- and environment-friendly antiwear additive packages have not presented popular or commonly used ZDDP-free products for the vehicle industry. This study presents tribological characterization of a newly developed ZDDP-free lubricating oil by engine bench tests.

Ionic liquid capped carbon dots as a high-performance friction-reducing and antiwear additive for poly(ethylene glycol)

This work presents ionic liquid capped carbon dots as a high-performance friction-reducing and antiwear additive for poly(ethylene glycol).