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Recovery and Recycling of Tungsten by Alkaline Leaching of Scrap and Charged Amino Group Assisted Precipitation
Makino T.a, Nagai S.b, Iskandar F.c, Okuyama K.b, Ogi T.b
a Cutting Tool RandD Division, Kyocera Corporation, Kagoshima Sendai Plant, Satsumasendai, Kagoshima, 895-0292, Japan
b Department of Chemical Engineering, Hiroshima University, Hiroshima, 739-8527, Japan
c Department of Physics, Institute of Technology Bandung, Bandung West Java, 40132, Indonesia
[vc_row][vc_column][vc_row_inner][vc_column_inner][vc_separator css=”.vc_custom_1624529070653{padding-top: 30px !important;padding-bottom: 30px !important;}”][/vc_column_inner][/vc_row_inner][vc_row_inner layout=”boxed”][vc_column_inner width=”3/4″ css=”.vc_custom_1624695412187{border-right-width: 1px !important;border-right-color: #dddddd !important;border-right-style: solid !important;border-radius: 1px !important;}”][vc_empty_space][megatron_heading title=”Abstract” size=”size-sm” text_align=”text-left”][vc_column_text]© 2018 American Chemical Society.Herein, we present a charged amino group assisted precipitation (CAAP) method for recovery and recycling of high-purity tungsten from a solution obtained by alkaline leaching of cemented carbide (WC-Co alloy) scrap. When lysine hydrochloride, which contains a charged amino group (NH3+), was added to an alkaline leaching solution containing tungsten (307 mmol L-1), sodium (1236 mmol L-1), and vanadium (1.7 mmol L-1), over 90% of the tungsten was rapidly recovered as a lysine-tungsten precipitate. The sodium in the precipitate was successfully removed by a simple washing process. Calcination was then performed to obtain 99.6% high-purity tungsten oxide, and reduction and carburization of the obtained tungsten oxide resulted in tungsten carbide. A pilot study using the CAAP method demonstrated a considerable decrease (60%) in the displacement (i.e., volume of chemicals used/waste created) compared with that required for the conventional ion-exchange method for tungsten recycling.[/vc_column_text][vc_empty_space][vc_separator css=”.vc_custom_1624528584150{padding-top: 25px !important;padding-bottom: 25px !important;}”][vc_empty_space][megatron_heading title=”Author keywords” size=”size-sm” text_align=”text-left”][vc_column_text]Alkaline leaching,Alkaline leaching solutions,Cemented carbides,Ion-exchange methods,Lysine,Polyoxometalates,Precipitant,Washing process[/vc_column_text][vc_empty_space][vc_separator css=”.vc_custom_1624528584150{padding-top: 25px !important;padding-bottom: 25px !important;}”][vc_empty_space][megatron_heading title=”Indexed keywords” size=”size-sm” text_align=”text-left”][vc_column_text]Lysine,Polyoxometalate,Precipitant,Recovery,Urban mining[/vc_column_text][vc_empty_space][vc_separator css=”.vc_custom_1624528584150{padding-top: 25px !important;padding-bottom: 25px !important;}”][vc_empty_space][megatron_heading title=”Funding details” size=”size-sm” text_align=”text-left”][vc_column_text]This work was supported by JSPS (Japan Society for the Promotion of Science) KAKENHI (Grant No. 26709061) and the Steel Foundation for Environmental Protection Technology. This work was partly supported by the Center for Functional Nano Oxide at Hiroshima University (Japan). The authors thank Y. Sakamoto, T. Kondo, and H. Horiuchi for help with experiments and measurements. We also thank Sohei Okazaki for help with Rietveld analysis. We thank Gabrielle David, Ph.D., from Edanz Group (www.edanzediting.com/ac) for editing a draft of this manuscript.[/vc_column_text][vc_empty_space][vc_separator css=”.vc_custom_1624528584150{padding-top: 25px !important;padding-bottom: 25px !important;}”][vc_empty_space][megatron_heading title=”DOI” size=”size-sm” text_align=”text-left”][vc_column_text]https://doi.org/10.1021/acssuschemeng.7b04689[/vc_column_text][/vc_column_inner][vc_column_inner width=”1/4″][vc_column_text]Widget Plumx[/vc_column_text][/vc_column_inner][/vc_row_inner][/vc_column][/vc_row][vc_row][vc_column][vc_separator css=”.vc_custom_1624528584150{padding-top: 25px !important;padding-bottom: 25px !important;}”][/vc_column][/vc_row]