The impact of solid additives on the apparent solubility of hydrogen in petroleum fractions and model hydrocarbon liquids

Hydrogen is a key reagent in the petroleum and petrochemical industry. Thus , the intrinsic solubility of hydrogen in organic liquids of industrial int erest is an important parameter for process design and process modeling. Th e existing hydrogen solubility data base for industrial fluids is limited a nd does not account for the potential impact of trace additives such as cla y and catalyst fines, on the apparent solubility of hydrogen in these media . Such finely divided solids present large solid-liquid interfaces where hy drogen can sorb in competition with the Liquid media leading to an inadvert ent overestimation of the intrinsic hydrogen solubility. In this work, the effect of common solid additives on the apparent solubility of hydrogen in hydrocarbon liquids has been investigated. Hydrogen solubilities in hexadec ane, tetralin, and light and heavy virgin gas oils were measured with and w ithout the solid additives, including a commercial hydrotreating catalyst ( CHC), used CHC, CHC support, alumina, silica and carbon black. The measurem ents were made under a wide range of conditions: with upper limits of 380 d egreesC and 12.0 MPa. These solids all sorb hydrogen but only silica, used hydrotreating catalyst and hydrotreating catalyst support sorb significant amounts of hydrogen in the presence of liquid hydrocarbons. These latter th ree materials, present in many industrial heavy oil samples raise the appar ent solubility of hydrogen in these liquids. The presence of such solids is rarely reported even when present. Thus, two sets of hydrogen solubility i n heavy oil data exist in the literature - data where hydrogen solubility i s over stated due to the presence of such solids and data that are unaffect ed. (C) 2001 Published by Elsevier Science Ltd.