EP 3325679 A1 20180530 - METHOD FOR REDUCING TRIVALENT IRON IN THE PRODUCTION OF TITANIUM DIOXIDE ACCORDING TO THE SULFATE METHOD
Title (en)
METHOD FOR REDUCING TRIVALENT IRON IN THE PRODUCTION OF TITANIUM DIOXIDE ACCORDING TO THE SULFATE METHOD
Title (de)
VERFAHREN ZUR REDUKTION VON DREIWERTIGEM EISEN BEI DER HERSTELLUNG VON TITANDIOXID IM SULFATVERFAHREN
Title (fr)
PROCÉDÉ DE RÉDUCTION DE FER TRIVALENT DANS LA PRODUCTION DE DIOXYDE DE TITANE DANS LE PROCÉDÉ AU SULFATE
Publication
Application
Priority
- EP 15002178 A 20150723
- EP 2016001251 W 20160718
Abstract (en)
[origin: WO2017012710A1] The invention relates to the method step of reducing trivalent iron in the production of titanium dioxide according to the sulfate method. According to the invention, after the removal of the poorly soluble decomposition residue, the reduction occurs by means of metallic iron in such a way that the trivalent iron is completely reduced to divalent iron and tetravalent titanium is partially reduced to trivalent titanium in a deliberate manner. A Ti(III) content of 1 wt% to 5 wt% with respect to the total titanium is preferably sought. The method step according to the invention preferably occurs in continuous operation at a temperature of > 50°C to < 85°C in a reduction reactor, wherein the progress of the reduction is monitored by means of the redox potential or the iron(III) content or titanium(III) content of the solution. The method according to the invention is characterized by the following advantages: said method can be largely automated, the reduction reaction proceeds steadily, different scrap qualities can be used, and improved TiO2 product quality is achieved.
IPC 8 full level
C22B 3/08 (2006.01); C22B 3/22 (2006.01); C22B 3/44 (2006.01); C22B 34/12 (2006.01)
CPC (source: EP KR RU)
C01G 23/053 (2013.01 - RU); C01G 23/0532 (2013.01 - EP KR); C01G 49/14 (2013.01 - EP KR); C22B 3/08 (2013.01 - RU); C22B 3/22 (2013.01 - EP KR); C22B 3/44 (2013.01 - EP KR); C22B 34/125 (2013.01 - EP KR); C22B 34/1259 (2013.01 - EP KR); Y02P 10/20 (2015.11 - EP KR)
Citation (search report)
See references of WO 2017012710A1
Designated contracting state (EPC)
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 state (EPC)
BA ME
DOCDB simple family (publication)
EP 3121295 A1 20170125; AU 2016295915 A1 20171214; BR 112017025794 A2 20180807; CN 107849635 A 20180327; EP 3325679 A1 20180530; JP 2018523014 A 20180816; KR 20180031758 A 20180328; MX 2017015435 A 20180507; RU 2692544 C1 20190625; WO 2017012710 A1 20170126; WO 2017012710 A8 20180111
DOCDB simple family (application)
EP 15002178 A 20150723; AU 2016295915 A 20160718; BR 112017025794 A 20160718; CN 201680041560 A 20160718; EP 16763441 A 20160718; EP 2016001251 W 20160718; JP 2018503210 A 20160718; KR 20187005343 A 20160718; MX 2017015435 A 20160718; RU 2018106649 A 20160718