<?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>1870-249X</journal-id>
<journal-title><![CDATA[Journal of the Mexican Chemical Society]]></journal-title>
<abbrev-journal-title><![CDATA[J. Mex. Chem. Soc]]></abbrev-journal-title>
<issn>1870-249X</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Química de México A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1870-249X2011000300002</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Adsorption of Basic Chromium Sulfate Used in the Tannery Industries by Calcined Hydrotalcite]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[López Muñoz]]></surname>
<given-names><![CDATA[Beatriz Eugenia]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Rivera Robles]]></surname>
<given-names><![CDATA[Roberto]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Iturbe García]]></surname>
<given-names><![CDATA[José Luis]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Olguín Gutiérrez]]></surname>
<given-names><![CDATA[María Teresa]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Instituto Nacional de Investigaciones Nucleares Departamento de Química ]]></institution>
<addr-line><![CDATA[Ocoyoacac México]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>09</month>
<year>2011</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>09</month>
<year>2011</year>
</pub-date>
<volume>55</volume>
<numero>3</numero>
<fpage>137</fpage>
<lpage>141</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1870-249X2011000300002&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1870-249X2011000300002&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1870-249X2011000300002&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[The sorption behavior of the chemical species of Cr(III) from aqueous solutions by hydrotalcite calcined products was investigated considering the equilibrium pH (5.0 to 8.9) and the chromium concentration in aqueous solution (from 10.6 to 430.0 mmol/L) to obtain the corresponding isotherms. Each solution was prepared from basic Cr(III) sulphate which is a primary tanning agent used in the tannery industries. In this work no previous oxidation treatment was done to form Cr(VI) in order to remove the chromium from aqueous solutions by hydrotalcite. The amount of chromium in the remaining solutions after the sorption processes in a batch system by visible spectroscopy (Vis) was determined. The calcined hydrotalcite before and after the contact with the chromium(III) solutions by X-ray power diffraction (XRD), thermogravimetric analysis (TGA) and Fourier-transformed infrared (FT-IR) spectroscopy, were characterized. The specific area by Brunauer, Emmett and Teller (BET) method of each sample was also evaluated. It was found that under the experimental conditions of this work hydrolyzed species of Cr(III) are precipitated on the surface of the calcined hydrotalcite instead other adsorption mechanism, and the sulfate ions were the responsible to regenerated the crystalline structure of hydrotalcite, therefore the results are discussed in terms of both Cr(III) and sulfate chemical species.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[En este trabajo, se investigó el comportamiento de sorción de las especies químicas de Cr(III) en soluciones acuosas, en productos de calcinación de la hidrotalcita considerando tanto el pH al equilibrio (5.0 a 8.9) como las concentraciones de cromo en solución acuosa (desde 10.6 a 430.0 mmol/L), para obtener la isoterma correspondiente. Las soluciones se prepararon utilizando sulfato básico de Cr(III), el cual es el agente primario actualmente utilizado en la industria de la tenería. La cuantificación del cromo remanente en la solución, después del proceso de separación en un sistema por "lotes", se realizó por espectroscopia (Vis). La hirotalcita calcinada se caracterizó antes y después del contacto con las soluciones de Cr(III), por medio de difracción de rayos-X (DRX), análisis termogravimétrico (ATG) y espectroscopia infrarroja con transformada de Fourier (FT-IR). También se evaluó el área específica por el método de Brunauer, Emmett y Teller (BET), de cada muestra. Se encontró, que bajo las condiciones experimentales del presente trabajo, el mecanismo de separación es la precipitación de especies hidrolizadas del Cr(III), sobre la superficie de la hidrotalcita calcinada en lugar de otro mecanismo de adsorción, y que por otro lado, los iones sulfato fueron los responsables para regenerar la estructura de la hidrotalcita, por lo tanto los resultados se discuten en términos de las especies químicas de Cr(III) y del sulfato.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Chromium(III)]]></kwd>
<kwd lng="en"><![CDATA[Calcined hydrotalcite]]></kwd>
<kwd lng="en"><![CDATA[Adsorption]]></kwd>
<kwd lng="en"><![CDATA[Heavy metal]]></kwd>
<kwd lng="en"><![CDATA[Freundlich isotherm]]></kwd>
<kwd lng="es"><![CDATA[Cromo(III)]]></kwd>
<kwd lng="es"><![CDATA[Hidrotalcita calcinada]]></kwd>
<kwd lng="es"><![CDATA[Adsorción]]></kwd>
<kwd lng="es"><![CDATA[Metal pesado]]></kwd>
<kwd lng="es"><![CDATA[Isoterma de Freundlich]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[ <p align="justify"><font face="verdana" size="4">Article</font></p>     <p align="justify"><font face="verdana" size="4">&nbsp;</font></p>     <p align="center"><font face="verdana" size="4"><b>Adsorption of Basic Chromium Sulfate Used in the Tannery Industries by Calcined Hydrotalcite</b></font></p>     <p align="center"><font face="verdana" size="2">&nbsp;</font></p>     <p align="center"><font face="verdana" size="2"><b>Beatriz Eugenia L&oacute;pez Mu&ntilde;oz,<sup>*</sup> Roberto Rivera Robles, Jos&eacute; Luis Iturbe Garc&iacute;a, and Mar&iacute;a Teresa Olgu&iacute;n Guti&eacute;rrez</b></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><i>Instituto Nacional de Investigaciones Nucleares, Departamento de Qu&iacute;mica. Carretera M&eacute;xico Toluca S/N, La Marquesa, Ocoyoacac, M&eacute;xico, C.P. 52750, M&eacute;xico. </i> <a href="mailto:beatriz.lopez@inin.gob.mx">beatriz.lopez@inin.gob.mx</a>, <i>Tel.:+52 5553297200, fax: +52 5553297301.</i></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2">Received August 25, 2010.    <br> Accepted February 17, 2011.</font></p>     ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>Abstract</b></font></p>     <p align="justify"><font face="verdana" size="2">The sorption behavior of the chemical species of Cr(III) from aqueous solutions by hydrotalcite calcined products was investigated considering the equilibrium pH (5.0 to 8.9) and the chromium concentration in aqueous solution (from 10.6 to 430.0 mmol/L) to obtain the corresponding isotherms. Each solution was prepared from basic Cr(III) sulphate which is a primary tanning agent used in the tannery industries. In this work no previous oxidation treatment was done to form Cr(VI) in order to remove the chromium from aqueous solutions by hydrotalcite. The amount of chromium in the remaining solutions after the sorption processes in a batch system by visible spectroscopy (Vis) was determined. The calcined hydrotalcite before and after the contact with the chromium(III) solutions by X&#150;ray power diffraction (XRD), thermogravimetric analysis (TGA) and Fourier&#150;transformed infrared (FT&#150;IR) spectroscopy, were characterized. The specific area by Brunauer, Emmett and Teller (BET) method of each sample was also evaluated. It was found that under the experimental conditions of this work hydrolyzed species of Cr(III) are precipitated on the surface of the calcined hydrotalcite instead other adsorption mechanism, and the sulfate ions were the responsible to regenerated the crystalline structure of hydrotalcite, therefore the results are discussed in terms of both Cr(III) and sulfate chemical species. </font></p>     <p align="justify"><font face="verdana" size="2"><b>Keywords: </b>Chromium(III); Calcined hydrotalcite; Adsorption; Heavy metal; Freundlich isotherm.</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>Resumen</b></font></p>     <p align="justify"><font face="verdana" size="2">En este trabajo, se investig&oacute; el comportamiento de sorci&oacute;n de las especies qu&iacute;micas de Cr(III) en soluciones acuosas, en productos de calcinaci&oacute;n de la hidrotalcita considerando tanto el pH al equilibrio (5.0 a 8.9) como las concentraciones de cromo en soluci&oacute;n acuosa (desde 10.6 a 430.0 mmol/L), para obtener la isoterma correspondiente. Las soluciones se prepararon utilizando sulfato b&aacute;sico de Cr(III), el cual es el agente primario actualmente utilizado en la industria de la tener&iacute;a. La cuantificaci&oacute;n del cromo remanente en la soluci&oacute;n, despu&eacute;s del proceso de separaci&oacute;n en un sistema por "lotes", se realiz&oacute; por espectroscopia (Vis). La hirotalcita calcinada se caracteriz&oacute; antes y despu&eacute;s del contacto con las soluciones de Cr(III), por medio de difracci&oacute;n de rayos&#150;X (DRX), an&aacute;lisis termogravim&eacute;trico (ATG) y espectroscopia infrarroja con transformada de Fourier (FT&#150;IR). Tambi&eacute;n se evalu&oacute; el &aacute;rea espec&iacute;fica por el m&eacute;todo de Brunauer, Emmett y Teller (BET), de cada muestra. Se encontr&oacute;, que bajo las condiciones experimentales del presente trabajo, el mecanismo de separaci&oacute;n es la precipitaci&oacute;n de especies hidrolizadas del Cr(III), sobre la superficie de la hidrotalcita calcinada en lugar de otro mecanismo de adsorci&oacute;n, y que por otro lado, los iones sulfato fueron los responsables para regenerar la estructura de la hidrotalcita, por lo tanto los resultados se discuten en t&eacute;rminos de las especies qu&iacute;micas de Cr(III) y del sulfato.</font></p>     <p align="justify"><font face="verdana" size="2"><b>Palabras clave: </b>Cromo(III); Hidrotalcita calcinada; Adsorci&oacute;n; Metal pesado, Isoterma de Freundlich.</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><a href="/pdf/jmcs/v55n3/v55n3a2.pdf" target="_blank">DESCARGAR ART&Iacute;CULO EN FORMATO PDF</a></font></p>     ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>References</b></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">1. Faghihian, H.; Bowman, R. S. <i>Water Res. </i><b>2005</b>, <i>39</i>, 1099&#150;1104.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917405&pid=S1870-249X201100030000200001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">2. NTIS/EPA   430/977&#150;004,   <i>Environmental   Protection   Agency</i>, Washington D.C., <b>1977</b>.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917407&pid=S1870-249X201100030000200002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">3. Samadi, M. T.; Rahman, A. R.; Zarrabi, M.; Shahabi, E.; Sameei, F. <i>Environ. Technol. </i><b>2009</b>, <i>30</i>, 1023&#150;1029<b>.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917409&pid=S1870-249X201100030000200003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></b></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">4. Eary, L. E.; Rai, D. <i>Environ. Sci. Technol. </i><b>1987</b>, <i>21</i>, 1187&#150;1193.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917411&pid=S1870-249X201100030000200004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">5. Mart&iacute;nez&#150;Gallegos, S.; Mart&iacute;nez, V.; Bulbulian, S. <i>Sep. Sci. Technol. </i><b>2004</b>, <i>39</i>, 667&#150;681.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917413&pid=S1870-249X201100030000200005&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">6. Lazaridis, N. K.; Pandi, T. A.; Matis, K. A. <i>Ind. Eng. Chem. Res. </i><b>2004</b>, <i>43</i>, 2209&#150;2215.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917415&pid=S1870-249X201100030000200006&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">7. Stunzi, H.; Marty, W. <i>Inorg. Chem. </i><b>1983</b>, <i>22</i>, 2145&#150;2150.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917417&pid=S1870-249X201100030000200007&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">8. Thompson, M.; Connick, R. E. <i>Inorg. Chem</i>. <b>1981</b>, <i>20</i>, 2279&#150;2285.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917419&pid=S1870-249X201100030000200008&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">9. Finholt, J. E.; Thompson, M. E.; Connick, R. E. <i>Inorg. Chem. </i><b>1981</b>, <i>20</i>, 4151&#150;4155.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917421&pid=S1870-249X201100030000200009&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">10. Meyenburg, U.; Siroky, O.; Schwarzenbach, G. <i>Helv. Chim. Acta </i><b>1973</b>, <i>56</i>, 1099&#150;1114.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917423&pid=S1870-249X201100030000200010&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">11. Tavani, E. L.; Volzone, C. <i>J. Soc. Leather Technol. Chem. </i><b>1997</b>, <i>81</i>, 143&#150;148.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917425&pid=S1870-249X201100030000200011&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">12. Xu, Z. P.; Jin, Y.; Liu, S.; Hao, Z. P.; Lu, G. Q. <i>J. Colloid Interf. Sci. </i><b>2008</b>, <i>326</i>, 522&#150;529.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917427&pid=S1870-249X201100030000200012&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">13. Hermos&iacute;n, M. C.; Pavlovic, I.; Ulibarri, M. A.; Cornejo, J. <i>Water Res. </i><b>1996</b>, <i>30</i>, 171&#150;177.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917429&pid=S1870-249X201100030000200013&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">14. Ch&acirc;telet, L.; Bottero, J. Y.; Yvon, J.; Bouchelaghem, A. <i>Colloid Surf. </i><b>1996</b>, <i>111</i>, 167&#150;175.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917431&pid=S1870-249X201100030000200014&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">15. Fahim, R. B.; Gabr, R. M.; Zaki, M. I.; Mansour, S. A. A. <i>J. Colloid Interf. Sci. </i><b>1981</b>, <i>81</i>, 468&#150;476.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917433&pid=S1870-249X201100030000200015&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">16. Fouad, N. E.; Knozinger, H.; Zaki, M. I.; Mansour, S. A. A. <i>Z. Phys. Chem. </i><b>1991</b>, <i>171</i>, 75&#150;96.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917435&pid=S1870-249X201100030000200016&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">17. Zaki, M. I.; Fahim, R. B. <i>J. Thermal. Anal. </i><b>1986</b>, <i>31</i>, 825&#150;834.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917437&pid=S1870-249X201100030000200017&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">18. Nyberg, C.; Tengstal, C. G. <i>J. Chem. Phys. </i><b>1984</b>, <i>80</i>, 3463&#150;3468.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917439&pid=S1870-249X201100030000200018&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">19. Nyberg, C.; Uvdal, P. <i>J. Chem. Phys. </i><b>1986</b>, <i>84</i>, 4631&#150;4635.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917441&pid=S1870-249X201100030000200019&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">20. Burneau, A.; Barres, O.; Gallas, J. P.; Lavalley, J. C. <i>Langmuir </i><b>1990</b>, <i>6</i>, 1364&#150;1372.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917443&pid=S1870-249X201100030000200020&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">21. Del Arco, M.; Mart&iacute;n, C.; Mart&iacute;n, I.; Rives, V.; Trujillano, R. <i>Spectrochim. Acta </i><b>1993</b>, <i>49A</i>, 1575&#150;1582.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917445&pid=S1870-249X201100030000200021&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">22. Labajos, F. M.; Rives, V.; Ulibarri, M. A. <i>J. Mat. Sci. </i><b>1992</b>, <i>27</i>, 1546&#150;1552.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917447&pid=S1870-249X201100030000200022&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">23. Kirk, I.; Othmer, D. F. <i>Chromium and chromium alloys, Chromium compounds</i>, <i>Encyclopedia of chemical technology</i>, Vol. 6, New York, <b>1979</b>, 82&#150;120.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917449&pid=S1870-249X201100030000200023&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">24. Carott, P. J. M; Sheppard, N. <i>J. Chem. Soc., Faraday Trans. I. </i><b>1983</b>, <i>79</i>, 2425&#150;2437.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917451&pid=S1870-249X201100030000200024&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">25. Bish, D. L.; Livingston, A. <i>Mineral. Mag. </i><b>1981</b>, <i>44</i>, 339&#150;343.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917453&pid=S1870-249X201100030000200025&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">26. Drits, V. A.; Sokolova, G. V.; Cherkashin, V. I. <i>Clay Clay Miner. </i><b>1987</b>, <i>35</i>, 401&#150;417.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917455&pid=S1870-249X201100030000200026&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">27. Sato, T.; Fujita, H.; Endo, T.; Shimada, M.; Tsunashima, A. <i>React. Solids. </i><b>1988</b>, <i>5</i>, 219&#150;228.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917457&pid=S1870-249X201100030000200027&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">28. Rai, D. <i>Radiochim. Acta </i><b>1984</b>, <i>35</i>, 97&#150;106.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917459&pid=S1870-249X201100030000200028&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">29. Yang, J.&#150;K.; Park, H.&#150;J.; Lee, H.&#150;D.; Lee, S.&#150;M. <i>Colloids and Surfaces A: Physicochemical and Engineering Aspects </i><b>2009</b>, <i>337</i>, 154&#150;158.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917461&pid=S1870-249X201100030000200029&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">30. Rai, D.; Sass, B. M.; Moore, D. A. <i>Inorg. Chem. </i><b>1987</b>, <i>26</i>, 345&#150;349.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917463&pid=S1870-249X201100030000200030&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">31. Fendorf, S. E.; Zasoski, R. J. <i>Environ. Sci. Technol. </i><b>1992</b>, <i>26</i>, 79&#150;85.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917465&pid=S1870-249X201100030000200031&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">32. Fendorf, S. E.; Sparks, D. L. <i>Environ. Sci. Technol. </i><b>1994</b>, <i>28</i>, 290&#150;297.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917467&pid=S1870-249X201100030000200032&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">33. Hach Company ed., <i>Chromium trivalent, Hach Company Colorimetric Method, </i>U.S.A. <b>1993</b>, 2&#150;79, 2&#150;80.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=4917469&pid=S1870-249X201100030000200033&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      ]]></body><back>
<ref-list>
<ref id="B1">
<label>1</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Faghihian]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
<name>
<surname><![CDATA[Bowman]]></surname>
<given-names><![CDATA[R. S.]]></given-names>
</name>
</person-group>
<source><![CDATA[Water Res.]]></source>
<year>2005</year>
<volume>39</volume>
<page-range>1099-1104</page-range></nlm-citation>
</ref>
<ref id="B2">
<label>2</label><nlm-citation citation-type="">
<collab>NTIS</collab>
<collab>EPA</collab>
<source><![CDATA[430/977-004, Environmental Protection Agency]]></source>
<year>1977</year>
<publisher-loc><![CDATA[Washington^eD.C. D.C.]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B3">
<label>3</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Samadi]]></surname>
<given-names><![CDATA[M. T.]]></given-names>
</name>
<name>
<surname><![CDATA[Rahman]]></surname>
<given-names><![CDATA[A. R.]]></given-names>
</name>
<name>
<surname><![CDATA[Zarrabi]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Shahabi]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
<name>
<surname><![CDATA[Sameei]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
</person-group>
<source><![CDATA[Environ. Technol.]]></source>
<year>2009</year>
<volume>30</volume>
<page-range>1023-1029</page-range></nlm-citation>
</ref>
<ref id="B4">
<label>4</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Eary]]></surname>
<given-names><![CDATA[L. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Rai]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
</person-group>
<source><![CDATA[Environ. Sci. Technol.]]></source>
<year>1987</year>
<volume>21</volume>
<page-range>1187-1193</page-range></nlm-citation>
</ref>
<ref id="B5">
<label>5</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Martínez-Gallegos]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
<name>
<surname><![CDATA[Martínez]]></surname>
<given-names><![CDATA[V.]]></given-names>
</name>
<name>
<surname><![CDATA[Bulbulian]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
</person-group>
<source><![CDATA[Sep. Sci. Technol.]]></source>
<year>2004</year>
<volume>39</volume>
<page-range>667-681</page-range></nlm-citation>
</ref>
<ref id="B6">
<label>6</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lazaridis]]></surname>
<given-names><![CDATA[N. K.]]></given-names>
</name>
<name>
<surname><![CDATA[Pandi]]></surname>
<given-names><![CDATA[T. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Matis]]></surname>
<given-names><![CDATA[K. A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Ind. Eng. Chem. Res.]]></source>
<year>2004</year>
<volume>43</volume>
<page-range>2209-2215</page-range></nlm-citation>
</ref>
<ref id="B7">
<label>7</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Stunzi]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
<name>
<surname><![CDATA[Marty]]></surname>
<given-names><![CDATA[W.]]></given-names>
</name>
</person-group>
<source><![CDATA[Inorg. Chem.]]></source>
<year>1983</year>
<volume>22</volume>
<page-range>2145-2150</page-range></nlm-citation>
</ref>
<ref id="B8">
<label>8</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Thompson]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Connick]]></surname>
<given-names><![CDATA[R. E.]]></given-names>
</name>
</person-group>
<source><![CDATA[Inorg. Chem.]]></source>
<year>1981</year>
<volume>20</volume>
<page-range>2279-2285</page-range></nlm-citation>
</ref>
<ref id="B9">
<label>9</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Finholt]]></surname>
<given-names><![CDATA[J. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Thompson]]></surname>
<given-names><![CDATA[M. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Connick]]></surname>
<given-names><![CDATA[R. E.]]></given-names>
</name>
</person-group>
<source><![CDATA[Inorg. Chem.]]></source>
<year>1981</year>
<volume>20</volume>
<page-range>4151-4155</page-range></nlm-citation>
</ref>
<ref id="B10">
<label>10</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Meyenburg]]></surname>
<given-names><![CDATA[U.]]></given-names>
</name>
<name>
<surname><![CDATA[Siroky]]></surname>
<given-names><![CDATA[O.]]></given-names>
</name>
<name>
<surname><![CDATA[Schwarzenbach]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
</person-group>
<source><![CDATA[Helv. Chim. Acta]]></source>
<year>1973</year>
<volume>56</volume>
<page-range>1099-1114</page-range></nlm-citation>
</ref>
<ref id="B11">
<label>11</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Tavani]]></surname>
<given-names><![CDATA[E. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Volzone]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Soc. Leather Technol. Chem.]]></source>
<year>1997</year>
<volume>81</volume>
<page-range>143-148</page-range></nlm-citation>
</ref>
<ref id="B12">
<label>12</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Xu]]></surname>
<given-names><![CDATA[Z. P.]]></given-names>
</name>
<name>
<surname><![CDATA[Jin]]></surname>
<given-names><![CDATA[Y.]]></given-names>
</name>
<name>
<surname><![CDATA[Liu]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
<name>
<surname><![CDATA[Hao]]></surname>
<given-names><![CDATA[Z. P.]]></given-names>
</name>
<name>
<surname><![CDATA[Lu]]></surname>
<given-names><![CDATA[G. Q.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Colloid Interf. Sci.]]></source>
<year>2008</year>
<page-range>326</page-range><page-range>522-529</page-range></nlm-citation>
</ref>
<ref id="B13">
<label>13</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Hermosín]]></surname>
<given-names><![CDATA[M. C.]]></given-names>
</name>
<name>
<surname><![CDATA[Pavlovic]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<name>
<surname><![CDATA[Ulibarri]]></surname>
<given-names><![CDATA[M. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Cornejo]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Water Res.]]></source>
<year>1996</year>
<volume>30</volume>
<page-range>171-177</page-range></nlm-citation>
</ref>
<ref id="B14">
<label>14</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Châtelet]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Bottero]]></surname>
<given-names><![CDATA[J. Y.]]></given-names>
</name>
<name>
<surname><![CDATA[Yvon]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Bouchelaghem]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Colloid Surf.]]></source>
<year>1996</year>
<volume>111</volume>
<page-range>167-175</page-range></nlm-citation>
</ref>
<ref id="B15">
<label>15</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Fahim]]></surname>
<given-names><![CDATA[R. B.]]></given-names>
</name>
<name>
<surname><![CDATA[Gabr]]></surname>
<given-names><![CDATA[R. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Zaki]]></surname>
<given-names><![CDATA[M. I.]]></given-names>
</name>
<name>
<surname><![CDATA[Mansour]]></surname>
<given-names><![CDATA[S. A. A.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Colloid Interf. Sci.]]></source>
<year>1981</year>
<volume>81</volume>
<page-range>468-476</page-range></nlm-citation>
</ref>
<ref id="B16">
<label>16</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Fouad]]></surname>
<given-names><![CDATA[N. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Knozinger]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
<name>
<surname><![CDATA[Zaki]]></surname>
<given-names><![CDATA[M. I.]]></given-names>
</name>
<name>
<surname><![CDATA[Mansour]]></surname>
<given-names><![CDATA[S. A. A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Z. Phys. Chem.]]></source>
<year>1991</year>
<volume>171</volume>
<page-range>75-96</page-range></nlm-citation>
</ref>
<ref id="B17">
<label>17</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Zaki]]></surname>
<given-names><![CDATA[M. I.]]></given-names>
</name>
<name>
<surname><![CDATA[Fahim]]></surname>
<given-names><![CDATA[R. B.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Thermal. Anal.]]></source>
<year>1986</year>
<volume>31</volume>
<page-range>825-834</page-range></nlm-citation>
</ref>
<ref id="B18">
<label>18</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Nyberg]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Tengstal]]></surname>
<given-names><![CDATA[C. G.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Chem. Phys.]]></source>
<year>1984</year>
<volume>80</volume>
<page-range>3463-3468</page-range></nlm-citation>
</ref>
<ref id="B19">
<label>19</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Nyberg]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Uvdal]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Chem. Phys.]]></source>
<year>1986</year>
<volume>84</volume>
<page-range>4631-4635</page-range></nlm-citation>
</ref>
<ref id="B20">
<label>20</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Burneau]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Barres]]></surname>
<given-names><![CDATA[O.]]></given-names>
</name>
<name>
<surname><![CDATA[Gallas]]></surname>
<given-names><![CDATA[J. P.]]></given-names>
</name>
<name>
<surname><![CDATA[Lavalley]]></surname>
<given-names><![CDATA[J. C.]]></given-names>
</name>
</person-group>
<source><![CDATA[Langmuir]]></source>
<year>1990</year>
<volume>6</volume>
<page-range>1364-1372</page-range></nlm-citation>
</ref>
<ref id="B21">
<label>21</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Del Arco]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Martín]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Martín]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<name>
<surname><![CDATA[Rives]]></surname>
<given-names><![CDATA[V.]]></given-names>
</name>
<name>
<surname><![CDATA[Trujillano]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
</person-group>
<source><![CDATA[Spectrochim. Acta]]></source>
<year>1993</year>
<volume>49A</volume>
<page-range>1575-1582</page-range></nlm-citation>
</ref>
<ref id="B22">
<label>22</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Labajos]]></surname>
<given-names><![CDATA[F. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Rives]]></surname>
<given-names><![CDATA[V.]]></given-names>
</name>
<name>
<surname><![CDATA[Ulibarri]]></surname>
<given-names><![CDATA[M. A.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Mat. Sci.]]></source>
<year>1992</year>
<volume>27</volume>
<page-range>1546-1552</page-range></nlm-citation>
</ref>
<ref id="B23">
<label>23</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kirk]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<name>
<surname><![CDATA[Othmer]]></surname>
<given-names><![CDATA[D. F.]]></given-names>
</name>
</person-group>
<source><![CDATA[Chromium and chromium alloys, Chromium compounds, Encyclopedia of chemical technology]]></source>
<year>1979</year>
<volume>6</volume>
<page-range>82-120</page-range><publisher-loc><![CDATA[New York ]]></publisher-loc>
</nlm-citation>
</ref>
<ref id="B24">
<label>24</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Carott]]></surname>
<given-names><![CDATA[P. J. M]]></given-names>
</name>
<name>
<surname><![CDATA[Sheppard]]></surname>
<given-names><![CDATA[N.]]></given-names>
</name>
</person-group>
<source><![CDATA[J. Chem. Soc., Faraday Trans. I.]]></source>
<year>1983</year>
<volume>79</volume>
<page-range>2425-2437</page-range></nlm-citation>
</ref>
<ref id="B25">
<label>25</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bish]]></surname>
<given-names><![CDATA[D. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Livingston]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Mineral. Mag.]]></source>
<year>1981</year>
<volume>44</volume>
<page-range>339-343</page-range></nlm-citation>
</ref>
<ref id="B26">
<label>26</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Drits]]></surname>
<given-names><![CDATA[V. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Sokolova]]></surname>
<given-names><![CDATA[G. V.]]></given-names>
</name>
<name>
<surname><![CDATA[Cherkashin]]></surname>
<given-names><![CDATA[V. I.]]></given-names>
</name>
</person-group>
<source><![CDATA[Clay Clay Miner.]]></source>
<year>1987</year>
<volume>35</volume>
<page-range>401-417</page-range></nlm-citation>
</ref>
<ref id="B27">
<label>27</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Sato]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Fujita]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
<name>
<surname><![CDATA[Endo]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Shimada]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Tsunashima]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<source><![CDATA[React. Solids.]]></source>
<year>1988</year>
<volume>5</volume>
<page-range>219-228</page-range></nlm-citation>
</ref>
<ref id="B28">
<label>28</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rai]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
</person-group>
<source><![CDATA[Radiochim. Acta]]></source>
<year>1984</year>
<volume>35</volume>
<page-range>97-106</page-range></nlm-citation>
</ref>
<ref id="B29">
<label>29</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Yang]]></surname>
<given-names><![CDATA[J.-K.]]></given-names>
</name>
<name>
<surname><![CDATA[Park]]></surname>
<given-names><![CDATA[H.-J.]]></given-names>
</name>
<name>
<surname><![CDATA[Lee]]></surname>
<given-names><![CDATA[H.-D.]]></given-names>
</name>
<name>
<surname><![CDATA[Lee]]></surname>
<given-names><![CDATA[S.-M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Colloids and Surfaces A: Physicochemical and Engineering Aspects]]></source>
<year>2009</year>
<volume>337</volume>
<page-range>154-158</page-range></nlm-citation>
</ref>
<ref id="B30">
<label>30</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rai]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Sass]]></surname>
<given-names><![CDATA[B. M.]]></given-names>
</name>
<name>
<surname><![CDATA[Moore]]></surname>
<given-names><![CDATA[D. A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Inorg. Chem.]]></source>
<year>1987</year>
<volume>26</volume>
<page-range>345-349</page-range></nlm-citation>
</ref>
<ref id="B31">
<label>31</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Fendorf]]></surname>
<given-names><![CDATA[S. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Zasoski]]></surname>
<given-names><![CDATA[R. J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Environ. Sci. Technol.]]></source>
<year>1992</year>
<volume>26</volume>
<page-range>79-85</page-range></nlm-citation>
</ref>
<ref id="B32">
<label>32</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Fendorf]]></surname>
<given-names><![CDATA[S. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Sparks]]></surname>
<given-names><![CDATA[D. L.]]></given-names>
</name>
</person-group>
<source><![CDATA[Environ. Sci. Technol.]]></source>
<year>1994</year>
<volume>28</volume>
<page-range>290-297</page-range></nlm-citation>
</ref>
<ref id="B33">
<label>33</label><nlm-citation citation-type="">
<collab>Hach Company</collab>
<source><![CDATA[Chromium trivalent, Hach Company Colorimetric Method]]></source>
<year>1993</year>
<page-range>2-80</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
