Synthesis of Transition Metal Arsenides and Arsenic Metal Sulfides and Their Role in the Dearsenation of Shale Oils

✍ Scribed by G.H. Singhal; L.D. Brown; D.F. Ryan

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 165 KB
• Volume: 109
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1994.1095

✦ Synopsis

One of the chief problems in upgrading shale oil is the presence of inherent arsenic, which is known to poison downstream catalysts. Highly dispersed transition metal sulfides formed in situ from the decomposition of dithiocarbamate (DTC) complexes of transition metals show excellent potential as dearsenation agents. We have studied the reaction of these sulfides with various arsenic compositions, and characterized the metal arsenides and arsenic metal sulfides formed as well as the ease of their formation. Thus, the reaction of bis(butyldithiocarbamato)Ni, (NiBuDTC), with model compounds was very facile and gave NiAs, NiAsS, and (\mathrm{NiAs}{2{-x}} \mathrm{~S}_{\boldsymbol{x}}). In general the effectiveness of the sulfides for dearsenation followed the sequence (\mathrm{Ni}>\mathrm{Mo} \gtrdot \mathrm{Co}), while iron sulfides were totally ineffective. Based upon these results, tests where run in autoclaves (as well as a fixed-bed flow-through unit) with (\mathrm{Ni}) BuDTC and shale oil having 73 ppm inherent As. Under optimum conditions, dearsenation down to less than (1 \mathrm{ppm}) was obtained. 1994 Academic Press, Inc.