Maciej Wisniewski

Extraction of arsenic from sulphuric acid solutions by Cyanex 923

Abstract Extraction of As(III) and As(V) from sulphuric acids solutions of various concentration (50–200 g/l H 2 SO 4 ) with Cyanex 923 dissolved in Exxsol 220/230 (50% v/v) was studied. Cyanex 923 can be considered as an effective arsenic extractant which can extract both arsenic(V) and arsenic(III). The extraction of As(V) and As(III) increases from feeds containing higher concentrations of sulphuric acid. Simultaneously, increased co-extraction of sulphuric acid is observed. Water can be used for arsenic and H 2 SO 4 stripping.

Transport of iron ions from chloride solutions using cellulose triacetate matrix inclusion membranes with an ionic liquid carrier

In this study, liquid membranes denoted as polymer inclusion membranes (PIMs) consisting of cellulose triacetate (CTA) as a polymer matrix, o-nitrophenyl octyl ether (NPOE) as a plasticiser and phosphonium ionic liquids, trihexyltetradecylphosphonium chloride (Cyphos® IL 101) and trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl)phosphinate (Cyphos® IL 104), as carriers of metal ions were developed. The transport of Fe(II) and Fe(III) from chloride aqueous solutions across PIMs was investigated. It is shown that these phosphonium ionic liquids are effective carriers of Fe(III) ions through PIMs. While, for Fe(II), the highest value of extraction efficiency and recovery factor after 72 h does not exceed 40%, by contrast, the values of these parameters for Fe(III) transport ranged from 60% to almost 100%. Additionally, the results indicate the transport rate to be strongly influenced by the amount of carrier in the membrane. The highest initial flux of Fe(III) and permeability coefficient are noted for the membrane containing 40 mass % Cyphos® IL 101. However, it is shown that the transport of Fe(III) increases as the carrier content is increased then decreases at a content of the carrier equal to 40 mass %. It appears that the Fe(III)-carrier complex decomposes with difficulty at the interface of the membrane-receiving phase, hence leading to low values of recovery factor Fe(III).

Ionic Liquids in Separation of Metal Ions from Aqueous Solutions

Solvents and catalysts for organic reactions:  Friedel-Crafts reactions,  Alkylation,  Izomerisation,  Acylation,  Esterification,  Cracking,  Diels-Alder addition,  Wittig reactions,  Polymerisation. Solvents in separation processes:  Extraction of metals and organic compounds,  Nuclear wastewater treatment,  Production of selective liquid membranes and sensors. Others:  Electrolytes in chemical sources of energy,  Lubricants,  Plasticizers,  Bactericides,  Fungicides,  Antielectrostatic agents,  Selective absorber of sulphur compounds from gasoline and oils.