(19)

(11)

EP 3 740 597 A1

(12)

(43) Date of publication: 25.11.2020 Bulletin 2020/48 (21) Application number: 19702174.4 (22) Date of filing: 10.01.2019

(51) International Patent Classification (IPC):  C22B 1/14(2006.01) C21C 5/52(2006.01) C22C 22/00(2006.01) C22B 1/245(2006.01) C22B 1/244(2006.01) C22B 5/12(2006.01) C22C 35/00(2006.01) C22B 5/10(2006.01) (86) International application number: PCT/ZA2019/050002 (87) International publication number: WO 2019/144165 (25.07.2019 Gazette 2019/30)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA ME Designated Validation States: KH MA MD TN (30) Priority: 19.01.2018 ZA 201800379 (71) Applicant: Mintek 2194 Randburg (ZA)	(72) Inventors: BISAKA, Kabwika 2194 Randburg (ZA) MAKWARELA, Moyahabo Olive 2194 Randburg (ZA) ERWEE, Markus Wouter 2194 Randburg (ZA) TSEBE, Sello Peter 2194 Randburg (ZA) (74) Representative: Patentanwälte Ruff, Wilhelm, Beier, Dauster & Partner mbB  Kronenstraße 30 70174 Stuttgart 70174 Stuttgart (DE)