Open AccessCaO&CaSO4 and CaO&Al2(SO4)3 as Pectin Precipitants–Model of Overlapping Diffuse Layers
Author(s) -
Tatjana Kuljanin,
Vladimir Filipović,
Milica Nićetin,
Biljana Lončar,
Bojana V. Filipčev,
Lato Pezo
Publication year - 2018
Publication title -
periodica polytechnica. chemical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.322
H-Index - 19
eISSN - 1587-3765
pISSN - 0324-5853
DOI - 10.3311/ppch.12320
Subject(s) - pectin , chemistry , sugar beet , zeta potential , ion , yield (engineering) , surface charge , electrolyte , sugar , calcium , analytical chemistry (journal) , chromatography , thermodynamics , biochemistry , materials science , nanotechnology , organic chemistry , physics , electrode , nanoparticle , horticulture , biology
This work is concerned with the theoretical basis of novel sugar beet juice purification method using binary systems CaO&CaSO4 and CaO&Al2(SO4)3. The Gouy–Chapman–Stern (GCS) model of overlapping of diffuse layers of EDLs on pectin surface and that on Ca2+ and Al3+ ions, theoretically explains this method. The change of the zeta potential was used to quantitatively indicate overlapping of diffuse layers. For the experiment two model solutions of pectin (0.1 % w/w) were prepared, while the concentrations of CaO&CaSO4 and CaO&Al2(SO4)3 in the range of 50–500 g dm-3 were used. The greater decrease in the absolute value of zeta potential indicated greater overlapping of diffuse layers between pectin particles and Ca2+ and Al3+ ions and faster coagulation of pectin. The overlapping degree increased with increased concentration of these binary systems. Pectin with a greater surface charge and multivalent Al3+ from CaO&Al2(SO4), exerted a greater impact on the zeta potential. Optimal quantities of the applied binary mixtures were as follows: 256–640 mg g-1 pectin. This is much lower than CaO commonly used in the conventional process of sugar beet juice purification (about 9 g g-1 pectin).