title: Lead-binding capacity of calcium pectates with different molecular weight.
abstract: Nowadays, heavy metal contamination of environment is considered as a serious threat to public health because of toxicity of these pollutants and the lack of effective materials with metal-binding properties. Some biopolymers such as pectins were proposed for removal of metal ions from industrial water disposals. Chemical structure of pectins is quite variable and substantially affects their metal binding properties. In this work, relationship between molecular weight and Pb(II)-binding capacity of calcium pectates was investigated in a batch sorption system. The results showed that all pectate samples are able to form complexes with Pb(II) ions. The effects of contact time, pH of the media and equilibrium metal concentration on metal-binding process were tested in experiments. The equilibrium time min required for uptake of Pb(II) by pectate compounds was found to be 60min. Langmuir and Freundlich models were applied for description of interactions between pectates and metal ions. Binding capacity of low molecular pectate was highest among all the samples tested. Langmuir model was figured out to be the best fit within the whole range of pH values. These results demonstrate that calcium pectate with low molecular weight is more promising agent for elimination of Pb(II) ions from contaminated wastewaters.
authors.affiliation: School of Biomedicine, Far Eastern Federal University, Vladivostok, 690950, Russia; A.V. Zhirmunski Institute of Marine Biology, Far Eastern Branch of Russian Academy of Sciences, Vladivostok, 690041, Russia. Electronic address: khotimchenko.my@dvfu.ru.
authors.forename: Maksim
authors.initials: M
authors.lastname: Khotimchenko
authors.affiliation: School of Biomedicine, Far Eastern Federal University, Vladivostok, 690950, Russia.
authors.forename: Ksenia
authors.initials: K
authors.lastname: Makarova
authors.affiliation: School of Biomedicine, Far Eastern Federal University, Vladivostok, 690950, Russia; A.V. Zhirmunski Institute of Marine Biology, Far Eastern Branch of Russian Academy of Sciences, Vladivostok, 690041, Russia.
authors.forename: Elena
authors.initials: E
authors.lastname: Khozhaenko
authors.affiliation: A.V. Zhirmunski Institute of Marine Biology, Far Eastern Branch of Russian Academy of Sciences, Vladivostok, 690041, Russia.
authors.forename: Valeri
authors.initials: V
authors.lastname: Kovalev
mesh_terms: D000327:Adsorption; D002118:Calcium / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007854:Lead / Q000737:chemistry* / Q000302:isolation & purification; D008970:Molecular Weight; D010368:Pectins / Q000737:chemistry*; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D014874:Water Pollutants, Chemical; D007854:Lead; D010368:Pectins; D002118:Calcium
keywords: Calcium pectate; Lead ions; Molecular weight