New Directions in Inorganic and Metal-Organic Coordination Chemistry in Supercritical Fluids

Darr, Jawwad A.; Poliakoff, Martyn

doi:10.1021/cr970036i

Cited by 594 publications

(339 citation statements)

References 369 publications

(995 reference statements)

Supporting

Mentioning

320

Contrasting

Unclassified

Order By: Relevance

“…Many of these polar inorganic materials, used as homogeneous catalysts, have very low solubility in non-polar solvents, such as scCO 2 , when compared to common polar organic solvents. In fact, low solubility of key inorganic catalysts in scCO 2 severely limits their suitability for carrying out catalytic reactions to the extent where the reaction ceases to occur (3,7). Due to such difficulties, high temperature and pressure are employed to obtain sufficient solubility of the catalyst in order to drive the reaction forward.…”

Section: Introductionmentioning

confidence: 99%

Tuning catalyst solubility in CO₂by changing molar volume

Munshi

Ghosh

Beckman

et al. 2010

Green Chemistry Letters and Reviews

View full text Add to dashboard Cite

Poor-solvating property of supercritical carbon dioxide (scCO 2 ) has been a great challenge, which limits the use of CO 2 as a common ''green'' solvent. The present report describes that by increasing molar volume (v) and lowering the melting temperature, which lowers cohesive energy density or solubility parameter (d), it is possible to increase the solubility of metal-based catalysts in scCO 2 without using costly fluorinated or tailormade CO 2 -philic modifications. We have studied various chlorodistannoxanes (1) and CuÁb-diketonates (2) to support our views. The study of bio-diesel production and transesterification of hindered esters using 1 in scCO 2 shows a 2Á8-folds rate enhancement coupled with an easier catalyst and product separation than that in organic solvents. The methodology, which works at least within the range of Van der Waals sphere of interactions, can be useful to solubilizing the molecules in scCO 2 and carries great opportunity in catalysis as well as in separation science.

show abstract

Section: Introductionmentioning

confidence: 99%

Tuning catalyst solubility in CO₂by changing molar volume

Munshi

Ghosh

Beckman

et al. 2010

Green Chemistry Letters and Reviews

View full text Add to dashboard Cite

show abstract

“…Environmental applications, such as the extraction of heavy metals or radionuclides from contaminated soil or metal removal from industrial waste water, have been a major focus in recent years [1], [2]. The solubility of metal-organic compounds in supercritical fluids (SF) has been the matter of several publications and reviews [3], [4][5][6]. Systematic studies of the effect that the ligand has on the solubility of these compounds in SC-CO2 have been published for metal-diketonates [7,8] and metal dithiocarbamates [9,10].…”

Section: Introductionmentioning

confidence: 99%

The Evaluation of the Dithizone Performance as a Complexing Reagent for Supercritical Co2 Extraction of Heavy Metals From Aqueous Solutions

Halili¹,

Mele²,

Arbneshi³

et al. 2016

RAD Conference Proceedings

View full text Add to dashboard Cite

Abstract. Heavy metal ions in liquid samples, apart from classical methods of extraction, can also be efficiently and environmentally friendly extracted by the use of supercritical CO2, containing a suitable complexing agent -ligand. This study represents the experimental data for the extraction of three heavy metals (Cu, Zn and Cd) from aqueous samples in the presence of dithizone as a ligand. The extractions by supercritical CO2 were accomplished at p=120 bars with t=50°C through the use of the dynamic technique. After the CO2 addition to the aqueous solution containing corresponding heavy metal ions, the pressure and temperature were set and extraction was performed in three different time periods: 30, 60 and 120 min (t=const., p=const. with a CO2 flow rate of 2 mL min −1 ). Once the extraction was stopped, the CO2 was released slowly through a restrictor. Methanol was used as a modifier (v/v) 10% and the pH value was set to 10. After the accomplishment of the extraction process, the leftover aqueous solution in the extractor was analyzed for its metal content by the use of the Atomic Absorption Spectrophotometer (AAS). The overall performance of the use of the dithizone as a ligand in all three cases of heavy metal ions enhanced greatly the extraction efficiency of these ligand/metal species.

show abstract

“…Then the development of environmentally benign processes utilizing CO 2 has become a very attractive topic in recent years 1-3 . The special properties of supercritical fl uids (SCFs) give rise to a whole range of utilizations: reaction yields, rates, and selectivity can be adjusted by changing pressure; SCFs (especially CO 2 ) can be used as green solvents; mass transfer is improved for heterogeneous reactions due to the obviously increased solubility; and simultaneous reaction and separation may be achieved for some reactions 2, 4 . Synthesis of dimethyl carbonate (DMC) using CO 2 is one of the promising reactions for the purpose of the development of environmentally benign processes utilizing CO 2 .…”

Section: Introductionmentioning

confidence: 99%

Direct synthesis of dimethyl carbonate and propylene glycol using potassium bicarbonate as catalyst in supercritical CO₂

Wen

Zhang

Cang

et al. 2015

Polish Journal of Chemical Technology

View full text Add to dashboard Cite

The improved one-pot synthesis of dimethyl carbonate and propylene glycol from propylene oxide, supercritical carbon dioxide, and methanol with potassium bicarbonate as the catalyst has been reported in this paper. As far as we know, it is the fi rst time to use potassium bicarbonate only as the catalyst in the production process which is simple and cheap. Satisfactory conversion rate of propylene oxide and yield of the products could be achieved at the optimized conditions with quite a small amount of by-products. Our new method offers an attractive choice for the production of dimethyl carbonate in large-scale industry effi ciently and environmental friendly.

show abstract

New Directions in Inorganic and Metal-Organic Coordination Chemistry in Supercritical Fluids

Cited by 594 publications

References 369 publications

Tuning catalyst solubility in CO₂by changing molar volume

Tuning catalyst solubility in CO₂by changing molar volume

The Evaluation of the Dithizone Performance as a Complexing Reagent for Supercritical Co2 Extraction of Heavy Metals From Aqueous Solutions

Direct synthesis of dimethyl carbonate and propylene glycol using potassium bicarbonate as catalyst in supercritical CO₂

Contact Info

Product

Resources

About

New Directions in Inorganic and Metal-Organic Coordination Chemistry in Supercritical Fluids

Cited by 594 publications

References 369 publications

Tuning catalyst solubility in CO2by changing molar volume

Tuning catalyst solubility in CO2by changing molar volume

The Evaluation of the Dithizone Performance as a Complexing Reagent for Supercritical Co2 Extraction of Heavy Metals From Aqueous Solutions

Direct synthesis of dimethyl carbonate and propylene glycol using potassium bicarbonate as catalyst in supercritical CO2

Contact Info

Product

Resources

About

Tuning catalyst solubility in CO₂by changing molar volume

Tuning catalyst solubility in CO₂by changing molar volume

Direct synthesis of dimethyl carbonate and propylene glycol using potassium bicarbonate as catalyst in supercritical CO₂