Experimental modeling of platinum sorption on organic matter

摘要

In connection with the discovery of a new type of Pt deposit in low-rank brown coals and black shales, the interaction of Pt-bearing aqueous solutions with fractionated organic matter (asphaltenes and asphaltenic acids) was studied at 200-400 degrees C and 1 kbar total pressure. It was found that chemical sorption onto the organic matter lowers Pt content in the aqueous solutions by about two orders of magnitude relative to organic-free systems. Thermal maturation of the asphaltenes leads to its aromatization and concomitant sorption of Pt from n x 10(-4) mPt (mol per kg of dry matter) at 200 degrees C to n x 10(-2) mPt at 400 degrees C Thus, the Pt chemisorption on activated carbonized organic matter may be an effective mechanism of Pt accumulation in C-bearing rocks. (C) 2000 Elsevier Science Ltd. All rights reserved. [References: 31]