K. M. Agrawal

SOLUBILISED WAXES AND THEIR INFLUENCE ON THE FLOW PROPERTIES OF LUBE OIL BASE STOCKS

ABSTRACT The physico-chemical properties of Lubricating oil base stocks (LOBS) are generally influenced by the type/nature and concentration of solubilised waxes present in them. Detailed composition of the solubilised waxes, saturates and aromatics present in LOBS and its distillate fractions has been sludied. Further the influence of these solubilised waxes and as well of saturates/aromatics on the flow properties particularly pour point, viscosity and viscosity temperature relationship of LOBS sample and its distillate fractions have been investigated. The response of a commercial pour point depressant additive with varying composition of solubilised waxes in lube oil base stock sample has also been studied.

Fractionation and Characterization of Waxes

Abstract By using short path molecular distillation (SPD) and supercritical fluid extraction (SFE) techniques, petroleum waxes have been fractionated into different fractions. These wax fractions were analyzed for their composition and phase transitions by gas chromatography (GC) and differential scanning calorimetry (DSC). GC data and the DSC thermograms indicated that the waxes vary significantly in their properties and composition.

Studies on Carbon Number Distribution of High Melting Microcrystalline Waxes

Abstract Carbon number distribution of microcrystalline wax derived from tank sludges of Bombay High crude oil (India) and its various high melting fractions have been studied by High Temperature Gas Chromatography (HTGC). Binodal, Gaussian distribution and a wide range of alkanes, ranging from C21–C75, along with their many isomers with predominant alkanes being C40 and C67, have been observed in the microcrystalline wax. Higher melting wax fractions have Gaussian distribution.

Composition and Properties of Some Petroleum Waxes

Abstract Structural composition of paraffin waxes and soft wax fraction derived from microcrystalline wax were determined. Waxes were fractionated by multistage solvent crystallization at different temperatures. The n-alkane components of the waxes were separated by urea adduction. The average structural parameters of parent waxes, their fractions, and urea adductables were estimated by 1h and 13C NMR spectroscopy. The thermal parameters viz. phase transition temperature and the associated energy during phase transitions were determined by using DSC and correlated with the penetration temperature behavior of waxes. The carbon number distribution determined by GC for these waxes and their n-alkane components were also correlated with physical properties and thermal parameters.

STRUCTURAL CHARACTERIZATION OF SOLID n-PARAFFIN COMPONENTS DERIVED FROM MUKTA CRUDE OIL

ABSTRACT The total solid paraffins (boiling 270°C+) separated from Mukta crude by urea adduction and its narrow fractions were analysed for their structural composition by proton NMR, infrared spectroscopy and gas chromatography. It has been observed that CH2/CH3 ratio in these samples varies from 7·9 to 13·8 while their average carbon number ranges from 17 to 29·6. The CH2/CH3 ratio and chain length of paraffins increases with increase in boiling range of the fractions.

Physical Properties of Petroleum Waxes. I. Effect of Oil Content

Abstract The effect of oil content on the physical properties of five microcrystalline waxes having widely different oil content have been investigated. It has been observed that the physical properties are affected to a great extent by the variation in oil content. Oil content has a profound effect on viscosity, hardness, and crystallinity of waxes. The effect is not so profound in the case of melting point.

Study of Phase Transition in Hard Microcrystalline Waxes and Wax Blends by Differential Scanning Calorimetry

Abstract Phase transition temperature and associated energies in hard high melting microcrystalline waxes and its various blend with paraffin wax (melting range from 60 to 97°C) have been determined by DSC in both heating and cooling mode. The dependence of these on the composition and properties of waxes have been analyzed. The solid liquid transition temperature obtained by DSC has been compared with ASTM drop melting point of these wax samples. The present study has demonstrated that DSC can be of great use in identifying whether the wax sample is blend of different waxes or not.

PARAFFIN DEPOSITION AND VISCOSITY TEMPERATURE BEHAVIOUR OF ASSAM CRUDE OIL

ABSTRACT The rate of paraffin deposition at equilibrium under different flowing conditions, viz, flow rate, oil and cold surface temperatures, and also viscosity temperature behaviour of Assam crude having wax content 11·0 % wt. and pour point 30°C has been studied. The effect of various diluents viz commercial kerosene and diesel oil on paraffin deposition and viscosity temperature behaviour have been determined. Deposition data has also been quantified in the form of a regression equation. It has been observed that added solvent significantly effect the paraffin deposition and viscosity temperature behaviour.

Crystallinity and average carbon number of petroleum waxes by X-ray diffraction

ABSTRACT Crystallinity and average carbon number of different petroleum waxes have been determined by means of X-ray diffraction. The effect of oil and polymers, viz, polyethylene (PE) and ethylene vinyl acetate (EVA) co-polymer on the crystallinity and average carbon number of petroleum waxes have also been studied. Crystallinity data has been correlated with composition and properties of the waxes.

CHARACTERIZATION OF TOTAL WAXES DERIVED FROM SOME INDIAN CRUDE OILS BY FRACTIONATION

ABSTRACT Characterization of total refined waxes separated from Indian origin Ratna & BorhoHa crude oils have been made by fractionation. Solvent crystallization and vaccum distillation technique have been used for the fractionation of the waxes. The study indicated that each wax had different melting point distribution characteristics.