Anais do Congresso Anual da ABM


ISSN 2594-5327

69° Congresso Anual da ABM - Internacional vol. 69, num.69 (2014)


Título

EVALUATION OF THE EFFECT OF ACID TREATMENT ON WHITE BENTONITE

EVALUATION OF THE EFFECT OF ACID TREATMENT ON WHITE BENTONITE

DOI

10.5151/1516-392X-25124

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Resumo

Clays with high content of smectite are denominated bentonites, and are widely used in industry as, for example, agents for bleaching of vegetable oils, animals and minerals. For this use, the smectite clays are treated with inorganic acid of high concentration at temperatures under boiling point, which provide the bentonite´s bleaching power. In the present study, a sample of smectite from Cubati, Paraiba, Brazil, was submitted to treatment under moderate conditions (90°C, reaction times of 1, 6, 12, 18 and 24hours in close reactor, concentration of the aqueous solution of hydrochloric acid 1.5 M, acid solution/clay ratio of 1g/10mL), aiming to reduce impurities, responsible for the color of the clay, without causing significant changes in their structure. Thus, clay can be used in the cosmetics industry and other products with high added value. The treated clay was characterized by scanning electron microscopy (SEM), stereomicroscopy, energy dispersive X-ray detector (EDS) and X-ray diffraction (XRD). It was observed a bleaching in samples with time of 12h to 18h. With the DRX was possible to monitor the peak intensity of the clay structure and the sample with 12 hours of treatment was not significantly altered its crystalline structure, maintaining the peak clay at d001. The most pronounced changes in the bleaching occurred within the first 12 hours of acid treatment.

 

Clays with high content of smectite are denominated bentonites, and are widely used in industry as, for example, agents for bleaching of vegetable oils, animals and minerals. For this use, the smectite clays are treated with inorganic acid of high concentration at temperatures under boiling point, which provide the bentonite´s bleaching power. In the present study, a sample of smectite from Cubati, Paraiba, Brazil, was submitted to treatment under moderate conditions (90°C, reaction times of 1, 6, 12, 18 and 24hours in close reactor, concentration of the aqueous solution of hydrochloric acid 1.5 M, acid solution/clay ratio of 1g/10mL), aiming to reduce impurities, responsible for the color of the clay, without causing significant changes in their structure. Thus, clay can be used in the cosmetics industry and other products with high added value. The treated clay was characterized by scanning electron microscopy (SEM), stereomicroscopy, energy dispersive X-ray detector (EDS) and X-ray diffraction (XRD). It was observed a bleaching in samples with time of 12h to 18h. With the DRX was possible to monitor the peak intensity of the clay structure and the sample with 12 hours of treatment was not significantly altered its crystalline structure, maintaining the peak clay at d001. The most pronounced changes in the bleaching occurred within the first 12 hours of acid treatment.

Palavras-chave

Clays; Acid treatment; Industrial use

Clays; Acid treatment; Industrial use

Como citar

Christiano Gianesi Bastos Andrade; Camila Matini Matos; Valquiria de Fátima Justo; Maria das Graças da Silva Valenzuela; Cristina Volzone; Francisco Rolando Valenzuela Diaz. EVALUATION OF THE EFFECT OF ACID TREATMENT ON WHITE BENTONITE , p. 9035-9044. In: 69° Congresso Anual da ABM - Internacional, São Paulo - Brasil, 2014.
ISSN: 2594-5327 , DOI 10.5151/1516-392X-25124