<?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>2602-8484</journal-id>
<journal-title><![CDATA[FIGEMPA: Investigación y Desarrollo]]></journal-title>
<abbrev-journal-title><![CDATA[Figempa]]></abbrev-journal-title>
<issn>2602-8484</issn>
<publisher>
<publisher-name><![CDATA[Universidad Central de Ecuador ]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2602-84842018000100047</article-id>
<article-id pub-id-type="doi">10.29166/revfig.v1i1.821</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Uso de suelos calcinados para minimizar la eutrofización mediante adsorción de fosfatos en Chone, Ecuador]]></article-title>
<article-title xml:lang=""><![CDATA[Use of calcined soils to minimize eutrophication through adsorption of phosphates in Chone, Ecuador]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Palacios Orejuela]]></surname>
<given-names><![CDATA[Iván Fernando]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ushiña Huera]]></surname>
<given-names><![CDATA[Dennis Paúl]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Carrera Villacrés]]></surname>
<given-names><![CDATA[David Vinicio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,ESPE. Sangolquí  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Ecuador</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,ESPE. Sangolquí  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Ecuador</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,ESPE. Sangolquí  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Ecuador</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>5</volume>
<numero>1</numero>
<fpage>47</fpage>
<lpage>53</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://scielo.senescyt.gob.ec/scielo.php?script=sci_arttext&amp;pid=S2602-84842018000100047&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.senescyt.gob.ec/scielo.php?script=sci_abstract&amp;pid=S2602-84842018000100047&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.senescyt.gob.ec/scielo.php?script=sci_pdf&amp;pid=S2602-84842018000100047&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Los fosfatos presentes en la Presa Multipropósito Chone han ocasionado problemas de eutrofización en la cuenca del río Grande que provoca afectaciones del tipo social, ambiental y económico para la zona. Una solución es el uso de tecnosoles que son suelos propios de lugar a los cuales se les adiciona elementos ajenos para mejorar su capacidad de remoción de un contaminante específico, sin embargo, este estudio se basó únicamente en la modificación del suelo de Chone mediante su calcinación y así simular un tecnosol capaz de remover fosfatos en soluciones acuosas mediante su calcinación, proceso que provoca un cambio en las propiedades físicas y químicas al tiempo de volatilizar los compuestos orgánicos presentes. Para esto, se realizó una disolución con concentración de 1.25 mg/L de fosfato monobásico de potasio, semejante a la concentración presente en el río. Las concentraciones del adsorbato contenidas en el agua ya filtrada a través del suelo modificado fueron medidas con espectrofotómetro en 4 sesiones continuas a intervalos de 2 horas, la máxima adsorción fue del 92% al cabo de 7 horas de filtrado; la cinética de la adsorción estuvo dada por una reacción de primer orden, además, se obtuvo un mejor ajuste con la isoterma de Langmuir que representó una adsorción en monocapa de fosfatos. Se modeló el comportamiento de la adsorción del fosfato en software libre con el que se estimó un tiempo de saturación del adsorbente de 14 horas. Como conclusiones del trabajo se tiene que los valores de adsorción de fosfatos son mayores con el suelo modificado (92%) que con el suelo natural (40.05%); la calcinación del suelo proporcionó una reactividad de los compuestos férricos presentes en el adsorbente con un incremento de su área superficial, intercambio catiónico y por ende una mayor adsorción del contaminante.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract The phosphates present in the Presa Multipropósito Chone have caused eutrophication problems in the Rio Grande basin, causing social, environmental and economic impacts for the area. One solution is the use of technosols, which are soil added with foreign elements to improve their ability to remove a specific contaminant. However, this study was based on the modification of the Chone soil and thus simulated a technosol able of removing phosphates in aqueous solutions through its calcination, process that causes a change in the physical and chemical properties at the time of volatilizing the organic compounds present. For this, a solution with concentration of 1.25 mg/L of potassium phosphate monobasic was done, similar to the concentration present in the river. The concentrations of the adsorbate contained in the water already filtered through the modified soil were measured with a spectrophotometer in 4 continuous sessions at intervals of 2 hours, the maximum adsorption was 92% after 7 hours of filtering; the kinetics of the adsorption was given by a first-order reaction, in addition, a better fit was obtained with the Langmuir isotherm, which represented an adsorption in monolayer of phosphates. The behaviour of the adsorption of phosphate was modelled using free software, which was estimated an adsorbent saturation time of 14 hours. As conclusions of the work, phosphate adsorption values are higher with modified soil (92%) than with natural soil (40.05%); the calcination of the soil provided a reactivity of the ferric compounds present in the adsorbent with an increase in its surface area, cation exchange and therefore a greater adsorption of the contaminant.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[compuestos férricos]]></kwd>
<kwd lng="es"><![CDATA[fosfato monobásico de potasio]]></kwd>
<kwd lng="es"><![CDATA[isoterma de Langmuir]]></kwd>
<kwd lng="es"><![CDATA[tecnosoles]]></kwd>
<kwd lng="en"><![CDATA[ferric compounds]]></kwd>
<kwd lng="en"><![CDATA[potassium phosphate monobasic]]></kwd>
<kwd lng="en"><![CDATA[langmuir isotherm]]></kwd>
<kwd lng="en"><![CDATA[technosols]]></kwd>
</kwd-group>
</article-meta>
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