<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0122-5383</journal-id>
<journal-title><![CDATA[CT&F - Ciencia, Tecnología y Futuro]]></journal-title>
<abbrev-journal-title><![CDATA[C.T.F Cienc. Tecnol. Futuro]]></abbrev-journal-title>
<issn>0122-5383</issn>
<publisher>
<publisher-name><![CDATA[Instituto Colombiano del Petróleo (ICP) - ECOPETROL S.A.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0122-53832018000100045</article-id>
<article-id pub-id-type="doi">10.29047/01225383.90</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Finding a relationship between the composition and the emulsifying character of asphaltenes through FTICR-MS]]></article-title>
<article-title xml:lang="es"><![CDATA[Obteniendo una relación entre la composición y el carácter emulsionante de asfaltenos a partir de FTICR-MS]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Rojas-Ruiz]]></surname>
<given-names><![CDATA[Fernando A]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Orrego-Ruiz]]></surname>
<given-names><![CDATA[Jorge A]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Ecopetrol - Instituto Colombiano del Petróleo  ]]></institution>
<addr-line><![CDATA[Bucaramanga ]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2018</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2018</year>
</pub-date>
<volume>8</volume>
<numero>1</numero>
<fpage>45</fpage>
<lpage>52</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0122-53832018000100045&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0122-53832018000100045&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0122-53832018000100045&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT In this work, n-heptane insoluble fractions (asphaltenes) from six crude oils were analyzed by means of Fourier-transform ion cyclotron resonance mass spectrometry (FTICR MS) using both positive Atmospheric Pressure Photo Ionization (+) APPI and negative Electro-Spray Ionization (-) ESI in order to understand their water-oil emulsion stabilization capability on a molecular level basis. Through (+) APPI it was possible to obtain an overview of samples composition. By sorting as nitrogen sulfur and oxygen containing compounds, it was possible to compositionally distinguish the asphaltenes. Through (-) ESI, several differences were also observed by grouping the classes as oxygen (NxOy+NxOySz+Oy+OySz) and non oxygen containing classes (Nx+NxSz). The interactions of these two groups of compounds must be considered in order to understand the water-oil emulsion stability. It implies that the cores where nitrogen and sulfur are part may interact via n-n stacking, while the oxygen containing compounds may interact either via hydrogen bonding or via dipole forces with the aromatic aggregates (highly polarizable), forming potentially surface active aggregates. Thus, the rate between these two families of compounds may determine the surfactant character of asphaltenes at the water-oil interface. Bearing this in mind, an emulsion stability coefficient was proposed based on the relative abundances of some families of compounds detected by (-) ESI-FTICR-MS to explain the crude oils' tendency to form emulsions.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN En el presente trabajo, las fracciones iiinsolubles en n-heptano (asfaltenos) de seis crudos fueron analizadas por espectrometría de masas de resonancia Ion-Ciclotrón con transformada de Fourier (FT-ICR MS) utilizando ionización de presión atmosférica en modo positivo (+) APPI e ionización electro-spray en modo negativo, con el fin de comprender a nivel molecular su capacidad de estabilización de emulsiones agua-aceite. A través de (+) APPI, fue posible obtener una visión general de la composición de las muestras. Al ordenar los compuestos como azufrados-nitrogenados, y oxigenados fue posible distinguir composicionalmente los asfaltenos. A través de (-) ESI también se observaron varias diferencias, al agrupar los compuestos detectados como los que contienen oxígeno (NxOy + NxOySz + Oy + OySz) y los que no contienen oxígeno (Nx + NxSz). Las interacciones de estos dos grupos de compuestos deben considerarse para comprender la estabilidad de la emulsión agua-aceite. Esto implica que los núcleos donde el nitrógeno y el azufre son parte pueden interactuar mediante apilamiento n-n, mientras que los compuestos que contienen oxígeno pueden interactuar mediante enlaces de hidrógeno o mediante fuerzas dipolo con los agregados aromáticos (altamente polarizables) formando agregados superficialmente activos. Es decir, la relación entre estas dos familias de compuestos puede determinar el carácter tensioactivo de los asfaltenos en la interfaz agua-aceite. Teniendo esto en cuenta, se propuso un coeficiente de estabilidad de emulsiones basado en las abundancias relativas de algunas familias de compuestos detectadas por (-) ESI-FT-ICR.MS que permita luego explicar la tendencia de los aceites crudos a formar emulsiones.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Asphaltenes]]></kwd>
<kwd lng="en"><![CDATA[FTICR-MS]]></kwd>
<kwd lng="en"><![CDATA[Water-oil emulsions]]></kwd>
<kwd lng="en"><![CDATA[Electrospray ionization]]></kwd>
<kwd lng="es"><![CDATA[Asfaltenos]]></kwd>
<kwd lng="es"><![CDATA[FT-ICR-MS]]></kwd>
<kwd lng="es"><![CDATA[Emulsiones crudo-agua]]></kwd>
<kwd lng="es"><![CDATA[Lonización por electro-spray]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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