Catalytic Purification of Sulfur from Bituminous Impurity

Abstract

The aim of this study is to build a pilot plant system working in a continuous mode to purify sulfur from bituminous impurities. This study focused on the role of the added mineral salt of view to help choose and design the right and suitable purification reactor that is capable of overcoming any future problems and getting pure sulfur. The presence of these impurities deteriorates the specification of the produced sulfur and has to be removed from it. Two different processes were used in the mine both based on the carbonization of the bitumen (in two different ways) and then the separation of the carbonized material by filtration. Both processes suffered serious technical, ecological and economic problems. Search for another purification method that can overcome these problems continued, finally, it was possible to purify sulfur from accompanied bituminous impurities by treating raw sulfur at about (125-130 ºC) with certain metal salt for 10 minutes, then subjecting the mixture to a filtration step. No hydrogen sulfide gas was detected. The reaction conditions are quite mild compared with the conditions currently used in the Mishraq sulfur mine (440-500 ºC for ~ 2 hours), with a large percentage of sulfur being converted to sulfurous gases. Rather than carbonizing the bitumen, it is presumed that purification is accomplished through the formation of a complex between the hydrocarbon and the metal salt that can be deposited on the surface of the filter element. It is possible to recover the spent metal salt and reuse it again.