Efficient Chloride Salt Extraction of Platinum Group Metals from Spent Catalysts

Ilya Bronshtein, Yishay Feldman, Sana Shilstein, Ellen Wachtel, Igor Lubomirsky, Valery Kaplan

Research output: Contribution to journalArticle

Abstract

We show that platinum (Pt) and palladium (Pd) can be efficiently removed from spent catalytic converters by means of a sintering process involving chloride salts. For Pt, mixing the crushed catalyst in an aqueous solution of chloride salts at catalyst/salt weight ratios ranging from 2.5 to 6.7, followed by drying, and 2-h sintering in the reactor furnace at 1100 °C, results in extraction of 80 ± 4% of the metal. For Pd, the addition of fumed silica to the dry chlorination agents was necessary in order to optimize extraction using fractional factorial design of experiments (DOE). Maximum Pd extraction of 93 ± 5% was achieved at 1100 °C with weight ratios of the catalyst material: CaCl 2 ·2H 2 O:SiO 2  = 1:0.6:1.2. Application of a similar protocol to Pt-containing catalytic converters would be expected to result in a similar high level of extraction efficiency. The primary advantage of the proposed extraction process is that it does not involve hazardous chemicals, strong bases/acids, or corrosive gases, and produces, as a byproduct, only small quantities of nontoxic silicate waste.

Original languageEnglish
Pages (from-to)103-114
Number of pages12
JournalJournal of Sustainable Metallurgy
Volume4
Issue number1
DOIs
Publication statusPublished - Mar 1 2018

Fingerprint

Platinum
platinum
Chlorides
Salts
Metals
catalyst
chloride
salt
palladium
Palladium
Catalysts
metal
Catalytic converters
Sintering
Hazardous Substances
Silicates
Caustics
Chlorination
chlorination
Silicon Dioxide

Keywords

  • Chloride salt extraction
  • Factorial analysis
  • Precious metal recycling
  • Spent catalytic converter

ASJC Scopus subject areas

  • Metals and Alloys
  • Mechanics of Materials
  • Environmental Science (miscellaneous)

Cite this

Efficient Chloride Salt Extraction of Platinum Group Metals from Spent Catalysts. / Bronshtein, Ilya; Feldman, Yishay; Shilstein, Sana; Wachtel, Ellen; Lubomirsky, Igor; Kaplan, Valery.

In: Journal of Sustainable Metallurgy, Vol. 4, No. 1, 01.03.2018, p. 103-114.

Research output: Contribution to journalArticle

Bronshtein, Ilya ; Feldman, Yishay ; Shilstein, Sana ; Wachtel, Ellen ; Lubomirsky, Igor ; Kaplan, Valery. / Efficient Chloride Salt Extraction of Platinum Group Metals from Spent Catalysts. In: Journal of Sustainable Metallurgy. 2018 ; Vol. 4, No. 1. pp. 103-114.
@article{8176435fdc054fe3ba4ab040d0ec99d6,
title = "Efficient Chloride Salt Extraction of Platinum Group Metals from Spent Catalysts",
abstract = "We show that platinum (Pt) and palladium (Pd) can be efficiently removed from spent catalytic converters by means of a sintering process involving chloride salts. For Pt, mixing the crushed catalyst in an aqueous solution of chloride salts at catalyst/salt weight ratios ranging from 2.5 to 6.7, followed by drying, and 2-h sintering in the reactor furnace at 1100 °C, results in extraction of 80 ± 4{\%} of the metal. For Pd, the addition of fumed silica to the dry chlorination agents was necessary in order to optimize extraction using fractional factorial design of experiments (DOE). Maximum Pd extraction of 93 ± 5{\%} was achieved at 1100 °C with weight ratios of the catalyst material: CaCl 2 ·2H 2 O:SiO 2  = 1:0.6:1.2. Application of a similar protocol to Pt-containing catalytic converters would be expected to result in a similar high level of extraction efficiency. The primary advantage of the proposed extraction process is that it does not involve hazardous chemicals, strong bases/acids, or corrosive gases, and produces, as a byproduct, only small quantities of nontoxic silicate waste.",
keywords = "Chloride salt extraction, Factorial analysis, Precious metal recycling, Spent catalytic converter",
author = "Ilya Bronshtein and Yishay Feldman and Sana Shilstein and Ellen Wachtel and Igor Lubomirsky and Valery Kaplan",
year = "2018",
month = "3",
day = "1",
doi = "10.1007/s40831-017-0155-z",
language = "English",
volume = "4",
pages = "103--114",
journal = "Journal of Sustainable Metallurgy",
issn = "2199-3823",
publisher = "Springer International Publishing AG",
number = "1",

}

TY - JOUR

T1 - Efficient Chloride Salt Extraction of Platinum Group Metals from Spent Catalysts

AU - Bronshtein, Ilya

AU - Feldman, Yishay

AU - Shilstein, Sana

AU - Wachtel, Ellen

AU - Lubomirsky, Igor

AU - Kaplan, Valery

PY - 2018/3/1

Y1 - 2018/3/1

N2 - We show that platinum (Pt) and palladium (Pd) can be efficiently removed from spent catalytic converters by means of a sintering process involving chloride salts. For Pt, mixing the crushed catalyst in an aqueous solution of chloride salts at catalyst/salt weight ratios ranging from 2.5 to 6.7, followed by drying, and 2-h sintering in the reactor furnace at 1100 °C, results in extraction of 80 ± 4% of the metal. For Pd, the addition of fumed silica to the dry chlorination agents was necessary in order to optimize extraction using fractional factorial design of experiments (DOE). Maximum Pd extraction of 93 ± 5% was achieved at 1100 °C with weight ratios of the catalyst material: CaCl 2 ·2H 2 O:SiO 2  = 1:0.6:1.2. Application of a similar protocol to Pt-containing catalytic converters would be expected to result in a similar high level of extraction efficiency. The primary advantage of the proposed extraction process is that it does not involve hazardous chemicals, strong bases/acids, or corrosive gases, and produces, as a byproduct, only small quantities of nontoxic silicate waste.

AB - We show that platinum (Pt) and palladium (Pd) can be efficiently removed from spent catalytic converters by means of a sintering process involving chloride salts. For Pt, mixing the crushed catalyst in an aqueous solution of chloride salts at catalyst/salt weight ratios ranging from 2.5 to 6.7, followed by drying, and 2-h sintering in the reactor furnace at 1100 °C, results in extraction of 80 ± 4% of the metal. For Pd, the addition of fumed silica to the dry chlorination agents was necessary in order to optimize extraction using fractional factorial design of experiments (DOE). Maximum Pd extraction of 93 ± 5% was achieved at 1100 °C with weight ratios of the catalyst material: CaCl 2 ·2H 2 O:SiO 2  = 1:0.6:1.2. Application of a similar protocol to Pt-containing catalytic converters would be expected to result in a similar high level of extraction efficiency. The primary advantage of the proposed extraction process is that it does not involve hazardous chemicals, strong bases/acids, or corrosive gases, and produces, as a byproduct, only small quantities of nontoxic silicate waste.

KW - Chloride salt extraction

KW - Factorial analysis

KW - Precious metal recycling

KW - Spent catalytic converter

UR - http://www.scopus.com/inward/record.url?scp=85064155593&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85064155593&partnerID=8YFLogxK

U2 - 10.1007/s40831-017-0155-z

DO - 10.1007/s40831-017-0155-z

M3 - Article

VL - 4

SP - 103

EP - 114

JO - Journal of Sustainable Metallurgy

JF - Journal of Sustainable Metallurgy

SN - 2199-3823

IS - 1

ER -