Copper hexafluorosilicate hydrate

• CAS: 12062-24-7
• Catalog Number: ACM12062247
• Category: Main Products
• Molecular Weight: 205.62
• Molecular Formula: CuF6Si
• Synonyms: copper fluorosilicate
• IUPAC Name: CUPRIC FLUOROSILICATE
• Boiling Point: 19.5ºC at 760 mmHg
• Appearance: white powder/ colorless liquid
• Application: Copper hexafluorosilicate hydrate is a chemical compound that consists of blue, hygroscopic crystals. It is decomposed by heat and is soluble in water, with slight solubility in alcohol. This product is commonly used for dyeing and hardening white marble, as well as for treating grapevines affected by "white disease."
• Exact Mass: 204.89700

Case Study

Development of a Flame-Retardant Composite Coating Based on Copper Hexafluorosilicate Modification

Mykhalichko B, et al. Period. Polytech. Chem. Eng., 2022, 66(2), 304-312.

This work developed a novel flame-retardant coating for wood based on copper hexafluorosilicate (CuSiF6)-modified epoxy-amine composite. Compared with the unmodified epoxy-amine composite, the maximum temperature of the combustion gas of the CuSiF6-modified epoxy-amine composite was reduced by 204-327 °C, and the mass loss during combustion was reduced by 7.8-10.4%. In addition, the fire-retardant coating was applied to wood for fire tests, and the results showed that its flame retardant efficiency (FPE) could reach group I (flame retardant efficiency index ≤ 9 %).
Preparation of CuSiF6 modified flame-retardant composite coating
· The first method involves obtaining the polymer sample by mixing the flame retardant-hardener and the binder, namely the [Cu(eda) (deta)]SiF6 chelate complex with ED-20, until a dark blue thick mass is formed. This resulting polymer sample is denoted as ED/pepa/CuSiF6 (II).
· In the second method, ED-20 and pepa are stirred together for 5-10 minutes in specific ratios. Then, anhydrous copper(II) hexafluorosilicate is added to the mixture and stirred until a uniform consistency is achieved. The color change from light yellow to dark blue after adding CuSiF6 indicates the formation of the [Cu(eda)(deta)]SiF6 chelate complex due to the bonding of the inorganic copper(II) salt with pepa during the curing process of the composites.

CuSiF6 Used in the Sequential One-Step Synthesis Strategy for M-XF6-Based MOF Materials

Guillerm, Vincent, et al. Chemistry-A European Journal, 2017, 23(28), 6829-6835.

This work demonstrates the continuous, one-step spray-drying (SD) synthesis of several members of this isoreticular MOF family, which differ in their anion pillars (XF6=[SiF6]2- and [TiF6]2-), N-donating organic ligands (pyrazine and 4,4'-bipyridine), and metal ions (M=Co, Cu, and Zn). These synthesized M-XF6-based MOFs can be considered as "ready-to-use" adsorbents for CO2 and N2 adsorption. In the synthetic example of SIFSIX-3-Cu, copper hexafluorosilicate hydrate was used as the anion pillar.
Synthesis procedure of SIFSIX-3-Cu
· The one-step SD synthesis involved atomizing two methanolic solutions at 85 °C, one containing M-SiF6 (M = Co, Cu, Zn) and the other containing pyrazine (pyz), resulting in fine powders that were collected with minimal methanol (MeOH) to prevent air sensitivity.
· In the case of SIFSIX-3-Cu, a 6 mL methanolic solution of 300 mg (1.34 mmol) of CuSiF6·H2O and a 6 mL methanolic solution of 325 mg (4.05 mmol) of pyz were simultaneously spray-dried under specific conditions to produce a blue powder of SIFSIX-3-Cu. The powder was then collected with a minimal amount of MeOH (272 mg; 55% yield based on Cu).
· To evaluate the CO2 sorption properties of the as-made SIFSIX-3-M MOFs, their performance was compared to that of their bulk counterparts. The SD-synthesized SIFSIX-3-M powders collected in methanol were directly transferred to sorption cells, dried, and evacuated for 12 hours at 65 °C before measuring their CO2 uptake at 298 K.

Copper(II) coordination polymers of imdc from copper hexafluorosilicate hydrate

Abrahams, Brendan F., et al. CrystEngComm 15.45 (2013): 9729-9737.

The monovalent anion of 1,3-bis(carboxymethyl)imidazolium combines with Cu to form a wavy 2D coordination polymer of the composition [Cu 2(imdc)2 (CH3OH)2](BF4) 2·(CH3OH)(H2O) where copper acetate-like dimers linked by imdc ligands act as 4-linked centers. The cation sheets stack on top of each other in an A,B,A,B… fashion and produce a structure containing channels parallel to the plane of the network. Tetrafluoroborate anions are located in the channels between the sheets. Upon removal of coordinating and non-coordinating solvent molecules, a single-crystal-to-single-crystal transformation occurs, yielding similar compounds, but with the BFanions now coordinated. CO isotherms measured at 258 and 273 K show only modest CO uptake, but suggest that the sheets move apart at elevated pressure to accommodate guest molecules. A compound with a composition of [Cu3(OH)2(imdc)2]·SiF6·2H2O·2MeOH with a 3D network was formed by combining copper acetate, copper hexafluorosilicate and Himdc. In this structure, infinitely parallel Cu3(OH)2 chains are connected by bridging ligands to form channels with approximately triangular cross-sections.
4 mL of aqueous solution containing Himdc (45 mg, 0.24 mmol), Cu(OAc)2·H2O (106 mg, 0.53 mmol) and copper hexafluorosilicate (48 mg, 0.23 mmol) was mixed with 3 mL of MeOH, and the reaction mixture was sealed. Light blue crystals formed within 24 hours. The crystals were collected, washed with acetone and dried in air, with a yield of 40 mg.

Copper hexafluorosilicate to form metal-organic framework

Alduhaish, Osamah, et al. Crystal Growth & Design 18.8 (2018): 4522-4527.

Copper hexafluorosilicate and 1,4-bis(4-pyridyl)-2-trifluoromethylbenzene (bpb-CF3) were reacted via liquid phase diffusion to form a porous SIFSIX-type metal-organic framework [Cu(bpb-CF3)2(SiF6)] (UTSA-121) containing functional trifluoromethyl groups. Single crystal X-ray diffraction analysis of UTSA-121 showed that bpb-CF3 can well replace the prototype bipyridine ligand to form a non-interpenetrating pcu framework that is highly porous (void fraction = 65.7%) with three-dimensional cross-channels and functionalized trifluoromethyl groups on the pore surface. In addition, IAST calculations showed that UTSA-121a has higher adsorption selectivity for C2H2 and CO2 than CH4 and N2 under ambient conditions.
Purple cubic crystals of UTSA-121 were obtained by slowly diffusing 2 mL of 1,4-bis(4-pyridyl)-2-trifluoromethylbenzene (bpb-CF3, 0.1 mmol, 30.0 mg) methanol solution into copper hexafluorosilicate hydrate (0.15 mmol, 30.9 mg) aqueous solution (2 mL) and adding a MeOH/H2O mixture (1:1, 4 mL) buffer layer. After 10 days, the purple crystals were collected, washed with methanol, and then dried (yield: 62% based on bpb-CF3). IR /cm-1 (KBr): 1617 (s), 1486 (m), 1429 (m), 1327 (s), 1279 (w), 1259 (m), 1226 (m), 1189 (m), 1121 (s), 1080 (w), 1 048(w), 1014(w), 908(w), 826(s), 729(w), 687(s), 659(s), 605(m), 578(w), 557(w), 530(w), 485(w), 469(s).