<?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>2223-4861</journal-id>
<journal-title><![CDATA[Centro Azúcar]]></journal-title>
<abbrev-journal-title><![CDATA[cen. az.]]></abbrev-journal-title>
<issn>2223-4861</issn>
<publisher>
<publisher-name><![CDATA[Editorial Feijóo]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2223-48612021000400074</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[DETERMINACIÓN DE LAS CONDICIONES OPERACIONALES DEL PROCESO DE EXTRACCIÓN DE ÁCIDO HÚMICO A PARTIR DE LA CACHAZA]]></article-title>
<article-title xml:lang="en"><![CDATA[DETERMINATION OF OPERATIONAL CONDITIONS FOR THE HUMIC ACID FROM THE FILTER CAKE EXTRACTION PROCESS]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Pedroso Rodríguez]]></surname>
<given-names><![CDATA[Irina]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[González Sáez]]></surname>
<given-names><![CDATA[Lourdes Yamé]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Luis Orozco]]></surname>
<given-names><![CDATA[Jesús]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad de Matanzas Facultad de Ciencias Técnicas Departamento de Química]]></institution>
<addr-line><![CDATA[Matanzas ]]></addr-line>
<country>Cuba</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2021</year>
</pub-date>
<volume>48</volume>
<numero>4</numero>
<fpage>74</fpage>
<lpage>84</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_arttext&amp;pid=S2223-48612021000400074&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_abstract&amp;pid=S2223-48612021000400074&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_pdf&amp;pid=S2223-48612021000400074&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN  Introducción: El ácido húmico es un fertilizante de origen orgánico que mejora las condiciones del suelo y favorece el desarrollo de las plantas. La cachaza es un residuo de la producción de azúcar, una fuente rica y renovable de materia orgánica.  Objetivo: Determinar las condiciones operacionales del proceso de extracción de ácido húmico a partir de la cachaza.  Materiales y Métodos: La extracción se realiza en dos etapas, un tratamiento básico con hidróxido de sodio y luego con ácido sulfúrico. Se planifica un diseño experimental compuesto central, con los factores relación sólido-líquido y los tiempos de cada tratamiento. Se optimiza el proceso a partir gráficos de superficie de respuesta y se aplica un análisis de regresión múltiple para la obtención de los modelos matemáticos que permitan predecir las condiciones óptimas.  Resultados y Discusión: La cachaza presentó un contenido de materia orgánica de 74,57% lo que indica un alto grado de maduración de la fuente orgánica, además presenta un pH igual a 6,2 y 65,02% de humedad. Las condiciones óptimas obtenidas fueron relación sólido-líquido igual a 0,12 g/ml y 10 h de extracción en cada etapa, con un porcentaje de extracción de ácido húmico igual a 15,37% y un beneficio bruto de 694,23 $/h.  Conclusiones: En el proceso de extracción de ácido húmico a partir de la cachaza influyen para un 10% de nivel de significación la relación sólido-líquido y los tiempos de cada extracción. Se obtiene un 15,37% de extracción de materia orgánica en el ácido húmico.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT  Introduction: Humic acid is an organic origin fertilizer that improves soil conditions and favors the plants development. Filter cake, a waste from sugar production, is a rich and renewable source of organic matter.  Objective: To determine operational conditions of humic acid from filter cake extraction process  Materials and Methods: The extraction is carried out in two stages, a basic treatment with sodium hydroxide and then with sulfuric acid. A central compound experimental design is planned, with the solid-liquid ratio and treatment time as variable factors. The process is optimized from response surface graphs. Multiple regression analysis is applied to obtain the mathematical models that allow to predict optimal conditions.  Results and Discussion: Filter cake had a 74.57%, organic matter content which indicates a high degree of maturation of the organic source; in addition, it presents a pH equal to 6.2 and 65.02% of humidity. The optimal conditions obtained were solid-liquid ratio equal to 0.12 g/ml and 10 h of extraction in each stage, with a humic acid extraction percentage equal to 15.37% and a gross profit of 694.23 $/h.  Conclusions: With a 10% level of significance, solid-liquid ratio and extraction time, influence in humic acid from the filter cake extraction process. A 15.37% extraction of organic matter is obtained in humic acid.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[ácido húmico]]></kwd>
<kwd lng="es"><![CDATA[cachaza]]></kwd>
<kwd lng="es"><![CDATA[condiciones operacionales]]></kwd>
<kwd lng="es"><![CDATA[extracción]]></kwd>
<kwd lng="es"><![CDATA[optimización]]></kwd>
<kwd lng="en"><![CDATA[humic acid]]></kwd>
<kwd lng="en"><![CDATA[filter cake]]></kwd>
<kwd lng="en"><![CDATA[operations conditions]]></kwd>
<kwd lng="en"><![CDATA[extraction]]></kwd>
<kwd lng="en"><![CDATA[optimization]]></kwd>
</kwd-group>
</article-meta>
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