<?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>0120-5609</journal-id>
<journal-title><![CDATA[Ingeniería e Investigación]]></journal-title>
<abbrev-journal-title><![CDATA[Ing. Investig.]]></abbrev-journal-title>
<issn>0120-5609</issn>
<publisher>
<publisher-name><![CDATA[Facultad de Ingeniería, Universidad Nacional de Colombia.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0120-56092023000100011</article-id>
<article-id pub-id-type="doi">10.15446/ing.investig.95364</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Aqueous Recovery of Zinc and Lead from Coal Fly Ashes of a Colombian Thermoelectric Plant]]></article-title>
<article-title xml:lang="es"><![CDATA[Recuperación acuosa de zinc y plomo a partir de cenizas volantes de carbón de una planta termoeléctrica colombiana]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Borda]]></surname>
<given-names><![CDATA[Johana]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[González]]></surname>
<given-names><![CDATA[Claudia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Torres]]></surname>
<given-names><![CDATA[Robinson]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Pedagógica y Tecnológica de Colombia Facultad de Ingeniería ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Colombia</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Pedagógica y Tecnológica de Colombia Facultad de Ingenieria ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Colombia</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Universidad Pedagógica y Tecnológica de Colombia  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>04</month>
<year>2023</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>04</month>
<year>2023</year>
</pub-date>
<volume>43</volume>
<numero>1</numero>
<fpage>1</fpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0120-56092023000100011&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0120-56092023000100011&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0120-56092023000100011&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT A hydrometallurgical treatment under ambient conditions was proposed in order to eliminate and recover the lead and zinc contained in a sample of thermal coal fly ash used to produce energy. By using leaching solutions with conventional inorganic acids (HCl, HNO3, and H2SO4), ferric chloride, and sodium citrate, more than 90% zinc and approximately 40% lead were obtained. The most favorable leaching conditions were set at 0,5 M, with a pH value of 8 for citrate. Two leaching stages were necessary to optimize metal recovery: the first with nitric acid for zinc extraction and the second one with citrate for the lead. The sulfur phases of the metals limited a complete metal extraction.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN Se propuso un tratamiento hidrometalúrgico en condiciones ambientales para eliminar y recuperar el plomo y zinc contenidos en una muestra de cenizas volantes de carbón térmico que se utiliza para producir energía. Mediante el uso de soluciones de lixiviación con ácidos inorgánicos convencionales (HCl, HNO3 y H2SO4), cloruro férrico y citrato de sodio, se obtuvo más del 90 % de zinc y aproximadamente el 40 % de plomo. Las condiciones de lixiviación más favorables se establecieron en 0,5 M y un valor pH de 8 para el citrato. Fueron necesarias dos etapas de lixiviación para optimizar la recuperación de metales: la primera con ácido nítrico para la extracción de zinc y la segunda con citrato para el plomo. Las fases de azufre de los metales limitaron una completa extracción de metales.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[fly ash]]></kwd>
<kwd lng="en"><![CDATA[leaching]]></kwd>
<kwd lng="en"><![CDATA[HNO3]]></kwd>
<kwd lng="en"><![CDATA[sodium citrate]]></kwd>
<kwd lng="en"><![CDATA[zinc]]></kwd>
<kwd lng="en"><![CDATA[lead]]></kwd>
<kwd lng="es"><![CDATA[cenizas volantes]]></kwd>
<kwd lng="es"><![CDATA[lixiviación]]></kwd>
<kwd lng="es"><![CDATA[HNO3]]></kwd>
<kwd lng="es"><![CDATA[citrato de sodio]]></kwd>
<kwd lng="es"><![CDATA[zinc]]></kwd>
<kwd lng="es"><![CDATA[plomo]]></kwd>
</kwd-group>
</article-meta>
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