Thallium diphosphates

2020 ◽  
Vol 75 (11) ◽  
pp. 927-937
Author(s):  
Matthias Weil ◽  
Berthold Stöger

AbstractThree thallium(I) diphosphates with compositions Tl4P2O7, Tl2H2P2O7, Tl2H2P2O7(H2O)0.5 and the mixed-valent thallium(I,III) diphosphate Tl2P2O7 (= TlITlIIIP2O7) were obtained from aqueous solutions using an ion-exchange resin (Tl4P2O7), through thermal treatment of TlH2PO4 at 190 °C and subsequent crystallization from aqueous solutions (Tl2H2P2O7, Tl2H2P2O7(H2O)0.5), and from a phosphate flux at 220 °C (Tl2P2O7). The crystal structures of monoclinic Tl4P2O7 (C2/c, Z = 4) and orthorhombic Tl2H2P2O7 (Pbca, Z = 8) are unique, whereas monoclinic Tl2H2P2O7(H2O)0.5 (C2/c, Z = 8) is isotypic with its potassium analogue, and triclinic Tl2P2O7 (P$‾{1}$, Z = 4) crystallizes in the TlInAs2O7 structure type. The crystal structure of Tl2P2O7 is related to that of In2P2O7 (= InIInIIIP2O7; P21/c, Z = 4) by a translationengleiche group-subgroup relationship (t2). IR spectra of Tl4P2O7, Tl2H2P2O7 and Tl2P2O7 are reported and discussed.

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Matthias Weil ◽  
Berthold Stöger

AbstractThree thallium(I) diphosphates with compositions Tl4P2O7, Tl2H2P2O7, Tl2H2P2O7(H2O)0.5 and the mixed-valent thallium(I,III) diphosphate Tl2P2O7 (= TlITlIIIP2O7) were obtained from aqueous solutions using an ion-exchange resin (Tl4P2O7), through thermal treatment of TlH2PO4 at 190 °C and subsequent crystallization from aqueous solutions (Tl2H2P2O7, Tl2H2P2O7(H2O)0.5), and from a phosphate flux at 220 °C (Tl2P2O7). The crystal structures of monoclinic Tl4P2O7 (C2/c, Z = 4) and orthorhombic Tl2H2P2O7 (Pbca, Z = 8) are unique, whereas monoclinic Tl2H2P2O7(H2O)0.5 (C2/c, Z = 8) is isotypic with its potassium analogue, and triclinic Tl2P2O7 (P$‾{1}$, Z = 4) crystallizes in the TlInAs2O7 structure type. The crystal structure of Tl2P2O7 is related to that of In2P2O7 (= InIInIIIP2O7; P21/c, Z = 4) by a translationengleiche group-subgroup relationship (t2). IR spectra of Tl4P2O7, Tl2H2P2O7 and Tl2P2O7 are reported and discussed.


2019 ◽  
Vol 135 ◽  
pp. 52-57 ◽  
Author(s):  
Zhenxiong Ye ◽  
Lifeng Chen ◽  
Caocong Liu ◽  
Shunyan Ning ◽  
Xinpeng Wang ◽  
...  

2016 ◽  
Vol 32 (4) ◽  
pp. 129-140 ◽  
Author(s):  
Agnieszka Bożęcka ◽  
Monika Orlof-Naturalna ◽  
Stanisława Sanak-Rydlewska

Abstract Industrial waste solutions may contain toxic Pb, Cu, Cd and other metal ions. These ions may also be components of leachates in landfills of ores. The toxicity of the ionic forms of these metals is high. For this reason the paper presents the results of studies on one of the methods to reduce their concentration in aqueous solutions. The article presents the results of studies on the removal of Pb2+, Cd2+ and Cu2+ ions from model aqueous solutions with synthetic ion exchange resin C 160 produced by Purolite. The investigated ion exchanger contains sulfonic acid groups (-SO3H) in its structure and is a strongly acidic cation-exchange resin. The range of the studied initial concentrations of the Pb2+, Cd2+ and Cu2+ ions in the solutions was from 6.25 mg/L to 109.39 mg/L. The results confirmed that the used ion exchange resin C160 efficiently removes the above-mentioned ions from the studied solutions. The highest degree of purification was achieved in lead solutions for the assumed range of concentrations and conditions of the ion exchange process. It reached 99.9%. In the case of other solutions, the ion exchange process occurs with lower efficiency, however it remains high and amounts to over 90% for all the ions. The results of research were interpreted on the basis of the Langmuir adsorption model. For each studied ion, sorption capacity of the ion exchange resin increases until the saturation and equilibrium state is reached. Based on the interpretation of the Langmuir equation coefficients, an indication can be made that the studied ion exchange resin has a major sorption capacity towards the copper ions. In their case, the highest value of constant qmax was obtained in the Langmuir isotherm. For Cu2+ ions it was 468.42 mg/g. For Pb2+ and Cd2+ ions, this parameter reached the values of 112.17 mg/g and 31.76 mg/g, respectively. Ion exchange resin C 160 shows the highest affinity for the Pb2+ ions. In this case, the achieved value of coefficient b is highest and equals 1.437 L/mg.


2012 ◽  
Vol 550-553 ◽  
pp. 2333-2337
Author(s):  
Zhen Yu Li ◽  
Shuang Hu

The adsorption of hexavalent chromium [Cr(VI)] from aqueous solutions using weakly basic ion-exchange resin D301 was studied in this work. The result showed that the adsorption of Cr(VI) was strongly dependent on pH, the optimum condition was investigated at pH 2 and the maximum adsorption capacity was 247.71 mg g-1. The equilibrium datas were fitted well with Langmuir and Redlich–Peterson isotherm models. The pseudo-second-order rate equation was best represented by the adsorption process.


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