Introducing Bayer Liquor–Derived Geopolymers

Author(s):  
E. Jamieson ◽  
A. van Riessen ◽  
B. McLellan ◽  
B. Penna ◽  
C. Kealley ◽  
...  
Keyword(s):  
Proceedings ◽  
2021 ◽  
Vol 57 (1) ◽  
pp. 101
Author(s):  
Virgil Badescu ◽  
Raluca Senin

The aim of this article was the gas chromatography–mass spectrometry (GC-MS) analysis oforganic matter from a residual liquor sample (S.C. Alum S.A., Tulcea), extracted by the solid-phasemicroextraction method (SPMA) and derivatized with N-(tert-butyldimethylsilyl)-Nmethyltrifluoroacetamide(MTBSTFA) as the silylating agent. [...]


Author(s):  
Rodrigo Aparecido Moreno ◽  
Isabela Brandolis Alves Falconi ◽  
Thamiris Auxiliadora Martins Gonçalves ◽  
Roberto Seno Júnior ◽  
Denise Crocce Romano Espinosa ◽  
...  
Keyword(s):  

2010 ◽  
Vol 20 ◽  
pp. s165-s168 ◽  
Author(s):  
Ying ZHANG ◽  
Shi-li ZHENG ◽  
Hao DU ◽  
Shao-na WANG ◽  
Ying PENG ◽  
...  

2014 ◽  
Vol 68 (3) ◽  
pp. 357-362
Author(s):  
Zoran Obrenovic ◽  
Ljubica Nikolic ◽  
Radislav Filipovic ◽  
Marija Milanovic ◽  
Ivan Stijepovic

In the last decade, exploration of transition alumina phases with good adsorption properties has attracted a great research interest from both a fundamental and a practical point of view. The transition phases of alumina are metastable polymorphs of aluminum oxide formed through the thermal dehydration of aluminum trihydroxide and aluminum oxyhydroxide. Powder X-ray diffraction (XRD), Fourier-transformed infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and low-temperature nitrogen absorption studies were employed to trace the formation of the transition phases of alumina. In this work transition alumina powders were synthesized starting from sodium aluminate solution prepared from Bayer liquor. The neutralization of sodium aluminate solution was performed with the use of sulphuric acid, while glucose was added in the starting solution. In this way, the single phase nanocrystalline boehmite was obtained. As-synthesized boehmite powders have high surface area (above 360 m2/g) and the average crystallite size less than 5 nm. The results showed that the properties of the powders (structure, morphology) are strongly influenced by the initial pH value of sodium aluminate solution, as well as by the duration of neutralization step.


2007 ◽  
Vol 42 (6) ◽  
pp. 1004-1009 ◽  
Author(s):  
Mahyar Mazloumi ◽  
Hamed Arami ◽  
Razieh Khalifehzadeh ◽  
S.K. Sadrnezhaad

2011 ◽  
Vol 65 (3) ◽  
pp. 271-277
Author(s):  
Zoran Obrenovic ◽  
Radislav Filipovic ◽  
Marija Milanovic ◽  
Ivan Stijepovic ◽  
Ljubica Nikolic

Transition (active) phases of alumina were synthesized starting from sodium aluminate solution prepared out of Bayer liquor. The neutralisation of sodium aluminate solution was performed by sulphuric acid. Powder X-ray diffraction (XRD), Fourier-transformed infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and low-temperature nitrogen absorption studies were employed to trace the formation of the transition phases of alumina. The results show that the properties of the powders (phase composition, morphology and specific surface area) are strongly influenced by the initial pH value of the system, as well as by the duration of neutralisation step. It is possible to obtain powders with heterogeneous structure with dominant phase of bayerite, gibbsite or boehmit by tuning the pH and concentration of the starting sodium aluminate solution. The transition (active) phases of alumina (?- and ?-alumina) with high specific surface area (264-373 m2/g) are formed through the thermal dehydratation of aluminium hydroxide (bayerite and gibbsite) and aluminium oxyhydroxide (boehmite or pseudoboehmite) at the temperature of 500?C. Namely, bayerite and pseudoboehmite transforms to ?-phase of alumina upon heating, while gibbsite transforms to ?-phase, maintaining the parent morphology.


2020 ◽  
Vol 14 (2) ◽  
pp. 168-172
Author(s):  
Marija Milanovic ◽  
Zoran Obrenovic ◽  
Ivan Stijepovic ◽  
Ljubica Nikolic

Boehmite nanocrystalline powders were obtained by neutralization of Bayer liquor at 70?C with addition of glucose. Temperature of the neutralization induced formation of the flower-like morphology of the nanopowders. XRD and FTIR results confirmed that the single phase boehmite is formed without any other impurities. Calcination at 500?C led to the formation of transition -alumina with the retention of the flower-like morphology. Both as-synthesised and calcined powders possessed high specific surface area with mesopores between 3-6 nm in diameter. Relatively low temperature of neutralization as well as the use of low cost and ecologically friendly glucose as a surfactant are very promising for the possible application in the industrial production of alumina nanopowders.


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