SiliaMetS® Calculation of SiliaMetS to Use
To get an effective metal removal, the amount of SiliaMetS Metal Scavenger used is very important. You can determine by two different ways how much scavenger will be needed;
- from the residual concentration (more accurate method)
- from the amount of metal catalyst used (when the residual metal concentration is unknown)
From residual metal concentration (ppm)
Knowing the palladium (Pd) level in 800 g of material is 500 ppm, (the oxidation state does not affect the calculation).
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Data needed:
- Loading of the scavenger (SiliaMetS Thiol): 1.2 mmol/g
- Metal molecular weight: Ex. Pd = 106.42 g/mol
- Amount of product to be treated containing the Pd: Ex. 800 g
- Residual concentration of metal: Ex. 500 ppm of Pd
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1. Determine the amount of palladium to be scavenged |
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2. Calculate the amount of scavenger (SiliaMetS Thiol) to use (1 equivalent) |
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To scavenge 400 mg of palladium, 3.13 g of SiliaMetS Thiol is needed if using only one equivalent. However, it is highly recommend trying a minimum of 4 equivalents at first. In this case, the amount of SiliaMetS Thiol will be 4 times higher (4 x 3.13 g = 12.40 g).
Sometimes, the metal residual concentration is unknown. In such a case, the amount (g) of palladium to be scavenged can be replaced by the amount of metal catalyst used for the reaction:
From amount of metal catalyst used
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Data needed:
- Amount of metal catalyst used: Ex. 10 g of Pd(PPh3)4
- Metal catalyst molecular weight: Pd(PPh3)4 = 1155.56 g/mol
1. Determine the amount of palladium to be scavenged
The amount of SiliaMetS Thiol to be used can then be determined as stated above (see point 2. above). In this particular case, one equivalent of SiliaMetS Thiol corresponds to 7.20 g.
7 Item(s)
List Grid
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SiliaMetS® Thiol
SiliaMetS® Thiol (Si-Thiol) is a robust metal scavenger for a variety of metals including Pd, Pt, Cu, Ag and Pb under a wide range of conditions. It has been used in pharmaceutical processes up to the pilot plant scale. It is our most versatile metal scavenger and is the preferred metal scavenger for Pd(II), Cu, Ag, and Hg.
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SiliaMetS® Thiourea
SiliaMetS® Thiourea (Si-THU) is a versatile metal scavenger for all forms of palladium and is widely used in the pharmaceutical industry. It works particularly well in organic solvents. It can also be used to scavenge Ag, Pt, Ru, Rh and Hg. Once complexed with a transition metal, it has been reported as being an effective catalyst.
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SiliaMetS® Cysteine
SiliaMetS® Cysteine (Si-Cys) is the silica bound equivalent of the amino acid Cysteine. By attaching the molecule to the backbone via the amino group, the thiol group remains free and accessible for higher metal scavenging efficiency. It is a versatile metal scavenger for a variety of metals including Pd, Sn, Ru, Pt, Cu, Rh, Cd and Sc under a wide range of conditions and the preferred metal scavenger for tin residues.
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SiliaMetS® Dimercaptotriazine (DMT)
SiliaMetS® DMT (Si-DMT) is the silica bound equivalent of 2,4,6-trimercaptotriazine (trithiocyanuric acid). It is a versatile metal scavenger for a variety of metals including Cd, Co, Ni, Pd, Pt, Rh, and Ru under a wide range of conditions and the preferred metal scavenger for ruthenium catalysts.
TMT has been reported to efficiently remove palladium and heavy metals by precipitation. Unfortunately, its solubility in organic solvents causes problem. SiliaMetS DMT solves this issue and almost all solvents can now be used.
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SiliaMetS® TAAcOH
SiliaMetS® TAAcOH (SiliaMetS Triaminetetraacetic Acid) is a silica bound metal scavenger for Pd(0), Ni(0) and Cu. It is the supported version of EDTA in its free form. It is an effective scavenger for metals in low or zero oxidation states, which includes many of the most synthetically useful catalysts such as tetrakis-(triphenylphosphine)palladium(0).
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SiliaMetS® TAAcONa
SiliaMetS® TAAcONa or (or SiliaMetS Triaminetetraacetate, sodium salt) is a silica bound metal scavenger for Pd(II), Ni(II) and Cu. It is the supported version of EDTA in its sodium salt form. It is an effective scavenger for metals in higher oxidation state, 2+ or higher.
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SiliaMetS® Metal Scavenger Kit
Cysteine - DMT - Imidazole - Triamine - TAAcOH - TAAcONa - Thiol - Thiourea
7 Item(s)
List Grid
- Metal to Remove
- Phases
- Pore Size
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- 60 Å (6)
- Endcapping
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- Endcapped (7)
- Non-endcapped (2)
- Particle Size
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