This paper explores the application of Total Reflection X‐Ray Fluorescence (TXRF) spectrometry for chromate (CrO₄²⁻) and phosphate (PO₄³⁻) determinations in synthetic solutions after their adsorption onto dolomite. The competition between both contaminants is also evaluated. Adsorption processes are considered an inexpensive, non‐contaminating alternative for retaining, on a selected substrate, a variety of pollutants present in different effluents. For a specific adsorbent, an important factor to be taking into account is the competition among different possible species. Variables such as concentration, temperature, ionic strength and pH were evaluated. Dolomite, a natural mineral based on calcium and magnesium carbonates, was employed as adsorbent. TXRF is an efficient, fast trace element analytical technique and requires only minimum specimen preparation, for that reason is suitable for this study. The experiments were carried out in batch systems; pH and ionic strength of the solution were measured and controlled. The results obtained in individual systems (phosphate‐dolomite or chromate‐dolomite) indicate a 70.5% for phosphate and 22.7% for chromate removal. The adjustment of the ionic strength had no influence on the removal of the anions. According to this study, the adsorption of chromate was reduced to 14% when the pH increased; this fact did not affect phosphate removal. The removal of both ions increased at pH under than 6. The presence of both ions at different concentrations did not change the removal value for the phosphate, whereas the removal of chromate was almost null, indicating a strong interference of the phosphate in the removal of chromate.

中文翻译：

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全反射X射线荧光光谱法研究铬酸盐和磷酸盐在溶液中的吸附竞争

本文探讨了全反射X射线荧光（TXRF）光谱法在铬酸盐（CrO ₄ ²⁻）和磷酸盐（PO ₄ ³⁻）在合成溶液吸附到白云石上后进行测定。还评估了两种污染物之间的竞争。吸附过程被认为是一种廉价，无污染的替代方法，用于将选定废水中的各种污染物保留在选定的基材上。对于特定的吸附剂，要考虑的重要因素是不同可能物种之间的竞争。评价诸如浓度，温度，离子强度和pH的变量。白云石是一种基于碳酸钙和碳酸镁的天然矿物，被用作吸附剂。TXRF是一种高效，快速的痕量元素分析技术，只需要最少的样品准备，因此适用于本研究。实验在批处理系统中进行；测量和控制溶液的pH和离子强度。在单个系统（磷酸盐-白云石或铬酸盐-白云石）中获得的结果表明，磷酸盐的去除率为70.5％，铬酸盐的去除率为22.7％。离子强度的调节对阴离子的去除没有影响。根据这项研究，当pH值增加时，铬酸盐的吸附降低到14％。这个事实并不影响磷酸盐的去除。在pH低于6的情况下，两种离子的去除率均增加。两种浓度的两种离子的存在均不会改变磷酸盐的去除值，而铬酸盐的去除率几乎为零，表明磷酸盐强烈地干扰了磷酸盐的去除。铬酸盐。在单个系统（磷酸盐-白云石或铬酸盐-白云石）中获得的结果表明，磷酸盐的去除率为70.5％，铬酸盐的去除率为22.7％。离子强度的调节对阴离子的去除没有影响。根据这项研究，当pH值增加时，铬酸盐的吸附降低到14％。这个事实并不影响磷酸盐的去除。在pH低于6的情况下，两种离子的去除率均增加。两种浓度的两种离子的存在均不会改变磷酸盐的去除值，而铬酸盐的去除率几乎为零，表明磷酸盐强烈地干扰了磷酸盐的去除。铬酸盐。在单个系统（磷酸盐-白云石或铬酸盐-白云石）中获得的结果表明，磷酸盐的去除率为70.5％，铬酸盐的去除率为22.7％。离子强度的调节对阴离子的去除没有影响。根据这项研究，当pH值增加时，铬酸盐的吸附降低到14％。这个事实并不影响磷酸盐的去除。在pH低于6的情况下，两种离子的去除率均增加。两种浓度的两种离子的存在均不会改变磷酸盐的去除值，而铬酸盐的去除率几乎为零，表明磷酸盐强烈地干扰了磷酸盐的去除。铬酸盐。当pH值增加时，铬酸盐的吸附降低到14％。这个事实并不影响磷酸盐的去除。在pH低于6的情况下，两种离子的去除率均增加。两种浓度的两种离子的存在均不会改变磷酸盐的去除值，而铬酸盐的去除率几乎为零，表明磷酸盐强烈地干扰了磷酸盐的去除。铬酸盐。当pH值增加时，铬酸盐的吸附降低到14％。这个事实并不影响磷酸盐的去除。在pH低于6的情况下，两种离子的去除率均增加。两种浓度的两种离子的存在均不会改变磷酸盐的去除值，而铬酸盐的去除率几乎为零，表明磷酸盐强烈地干扰了磷酸盐的去除。铬酸盐。