Potentialization of bentonite properties as support in acid catalysts

Publication date: Available online 5 December 2019Source: Materials Research BulletinAuthor(s): Jahaziel Amaya, Luis Bobadilla, Lola Azancot, Miguel Centeno, Sonia Moreno, Rafael MolinaAbstractEnhancement of the main physicochemical properties of a natural bentonite was carried out by means of modifications using surfactant, reflux, microwave treatment and, subsequently, the incorporation of AlZr and AlCe species. The evolution of the main changes in each modification stage was evaluated by means of X-ray diffraction, N2 sortometry, scanning microscopy (SEM), NH3-TPD, NH3-DRIFTS and CO adsorption at low temperature. For the evaluation of the catalytic behavior, the dehydration-dehydrogenation reactions of 2-propanol and hydro-conversion of decane were used; both of which generate, in addition, information regarding the acidic properties of the materials. The correlation of the number, type and acid strength with the catalytic behavior, allowed establishing the effect produced by both the delamination method and the nature of the incorporated cation. This generated tools that allow controlling the physicochemical properties, and more specifically, the enhancement of the acidity of new supports based on this type of natural clay mineral.Graphical Abstract
Source: Materials Research Bulletin - Category: Materials Science Source Type: research

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Abstract CASE PRESENTATION: A 64-year-old man presented for consideration for lung transplant. He had a history of previous tobacco use, OSA on CPAP therapy, and gastroesophageal reflux disease. He worked as a design engineer. The patient had a 4-year history of dyspnea on exertion, followed with periodic CT scan of the chest. Nine months prior to his evaluation for lung transplant, the patient developed worsening of dyspnea, dry cough, poor appetite, and weight loss. At times, the cough was violent and associated with chest pressure. He was prescribed systemic corticosteroids and antibiotics without improvement. ...
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Source: Scandinavian Journal of Gastroenterology - Category: Gastroenterology Tags: Scand J Gastroenterol Source Type: research
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Source: Scandinavian Journal of Gastroenterology - Category: Gastroenterology Tags: Scand J Gastroenterol Source Type: research
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Source: Scandinavian Journal of Gastroenterology - Category: Gastroenterology Tags: Scand J Gastroenterol Source Type: research
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Source: Aktuelle Urologie - Category: Urology & Nephrology Authors: Tags: Aktuelle Urol Source Type: research
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