The determination of water in crude oil and transformer oil reference materials

Margolis, Sam A.; Hagwood, Charles
May 2003
Analytical & Bioanalytical Chemistry;May2003, Vol. 376 Issue 2, p260
Academic Journal
The measurement of the amount of water in oils is of significant economic importance to the industrial community, particularly to the electric power and crude oil industries. The amount of water in transformer oils is critical to their normal function and the amount of water in crude oils affects the cost of the crude oil at the well head, the pipeline, and the refinery. Water in oil Certified Reference Materials (CRM) are essential for the accurate calibration of instruments that are used by these industries. Three NIST Standard Reference Materials (SRMs) have been prepared for this purpose. The water in these oils has been measured by both coulometric and volumetric Karl Fischer methods. The compounds (such as sulfur compounds) that interfere with the Karl Fischer reaction (interfering substances) and inflate the values for water by also reacting with iodine have been measured coulometrically. The measured water content of Reference Material (RM) 8506a Transformer Oil is 12.1±1.9 mg kg-1 (plus an additional 6.2±0.9 mg kg-1 of interfering substances). The measured water content of SRM 2722 Sweet Crude Oil, is 99±6 mg kg-1 (plus an additional 5±2 mg kg-1 of interfering substances). The measured water content of SRM 2721 Sour Crude Oil, is 134±18 mg kg-1 plus an additional 807±43 mg kg-1 of interfering substances. Interlaboratory studies conducted with these oil samples (using SRM 2890, water saturated 1-octanol, as a calibrant) are reported. Some of the possible sources of bias in these measurements were identified, These include: improperly calibrated instruments, inability to measure the calibrant accurately, Karl Fischer reagent selection, and volatilization of the interfering substances in SRM 2721.


Related Articles

  • Removal of oil from oil/water emulsions using electroflotation process. Mansour, L. Ben; Chalbi, S. // Journal of Applied Electrochemistry;May2006, Vol. 36 Issue 5, p577 

    Dispersed oil was separated from oil�water emulsions in an electroflotation cell equipped with insoluble electrodes: titanium coated with ruthenium oxide as anode and stainless steel screen as cathode. The effect of operating parameters such as current density, oil concentration, flotation...

  • Separating Oil-Water Nanoemulsions using Flux-Enhanced Hierarchical Membranes. Solomon, Brian R.; Hyder, Md. Nasim; Varanasi, Kripa K. // Scientific Reports;7/4/2014, p1 

    Membranes that separate oil-water mixtures based on contrasting wetting properties have recently received significant attention. Separation of nanoemulsions, i.e. oil-water mixtures containing sub-micron droplets, still remains a key challenge. Tradeoffs between geometric constraints, high...

  • Application of gas/liquid two-phase flow in cross-flow microfiltration of oil-in-water emulsion; permeate flux and fouling mechanism analysis. Fouladitajar, Amir; Zokaee Ashtiani, Farzin; Valizadeh, Bardiya; Armand, Seyed Borhan; Izadi, Ramin // Desalination & Water Treatment;Feb2016, Vol. 57 Issue 10, p4476 

    The effects of gas–liquid two-phase flow regimes on permeate flux and fouling mechanisms were investigated in a gas sparging assisted microfiltration of oil-in-water emulsion. Different two-phase flow patterns were attained by introducing gas stream into the liquid phase. It was found...

  • Treatment of oil-in-water emulsion using tubular ceramic membrane acquired from locally available low-cost inorganic precursors. Vinoth Kumar, R.; Monash, P.; Pugazhenthi, G. // Desalination & Water Treatment;Dec2016, Vol. 57 Issue 58, p28056 

    This article highlights the fabrication of ceramic membrane with tubular configuration using locally available inexpensive clays and its application in oil-in-water emulsion treatment. Extrusion technique was employed to manufacture the tubular-shaped ceramic membrane having length, outer, and...

  • Feasibility Study on Membrane Technology for Ship Oil-Water Separation in China. Ouchen Cai; Junfeng Chen; Wei Zhang // Advanced Materials Research;2014, Vol. 1092-1093, p856 

    The case study of membrane technology applied in oily water treatment in petrochemical industry demonstrated that it is also technically feasible in ship oil-water separation in China. Based on the analysis of the membrane technological parameter selection, a practical ship oil-water separator...

  • Effect of hydrophilic modification with nano-titania and operation modes on the oil–water separation performance of microfiltration membrane. Chang, Qibing; Wang, Xia; Wang, Yongqing; Zhang, Xiaozhen; Cerneaux, Sophie; Zhou, Jian-er // Desalination & Water Treatment;Mar2016, Vol. 57 Issue 11, p4788 

    The tubular Al2O3microfiltration membranes modified with nano-TiO2coating were applied in the separation of waste oil-in-water emulsion. The separation performances of the MF membranes with and without nano-TiO2modification were studied under two different operation modes, i.e. the circulation...

  • Modelling sweetness and texture perception in model emulsion systems. Tracey Hollowood; Sara Bayarri; Luca Marciani; Johanneke Busch; Susan Francis; Robin Spiller; Andrew Taylor; Joanne Hort // European Food Research & Technology;Jun2008, Vol. 227 Issue 2, p537 

    Abstract  Model emulsion samples, prepared subject to a d-optimal response surface design, were used to investigate the effect of rapeseed oil, sugar and hydroxypropyl methyl cellulose thickener (HPMC) on perceived sweetness, textural attributes (thickness, stickiness, mouth-coating,...

  • Applicability of Rheological Models of Flow to Stearate-Stabilized Emulsions. Moukhtarova, S. E.; Krivoshchepov, A. F.; Kim, V. E. // Colloid Journal;Jan/Feb2004, Vol. 66 Issue 1, p112 

    The applicability of rheological models of flow to the description of structural�mechanical properties of stearate-stabilized emulsions is considered. The strengths of individual contacts are calculated within the framework of the Casson model.

  • New route to soluble conductive polyaniline promises improved anticorrosive coatings.  // Chemical Business;Oct96, Vol. 10 Issue 4, p25 

    Features Monsanto Co.'s polyaniline emulsion that is readily miscible with several common coating resins. Properties of polyaniline; Key applications; Details published in 1996 issue of `Chemical Engineering.'


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics