COMPLEX EQUILIBRIA IN THE SYSTEM M2+-POLYGALACTURONIC ACID (PECTIN) - H2O (M=CO, NI, CU, ZN, CD AND PB)

被引:9
作者
DAVARSKI, KA
MANOLOV, SN
PETROVA, IN
MAVROV, VD
机构
[1] Department of Inorganic Chemistry, Bourgas University of Technology, Bourgas
关键词
PECTINS; POLYGALACTURONIC ACID; TRANSITION METALS; COMPLEXES; STABILITY CONSTANTS; ULTRAFILTRATION;
D O I
10.1080/00958979408024264
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
Ionisation constants for polygalacturonic acid (pectin) were determined by pH-metric titration in aqueous solution at different temperatures (283, 293, 303 and 313 K) and ionic strengths (0.1, 0.5, 1.0, 1.5 and 2.0), maintained with NaNO3. Complexing of pectin with Co2+, Ni2+, Cu2+, Zn2+, Cd2+, and Pb2+ under the same conditions and M:L ratios of 1:2 or 1:4 was studied. It was found that ML complexes prevail. Stability constants were evaluated. Complexformation is a result of favourable entropy changes, whereas there is no significant change of enthalpy. The possibility of metal extraction by complex formation and ultrafiltration was examined. Selectivities in ultrafiltration and productivities of membranes for Cu2+ complexes of pectin were determined.
引用
收藏
页码:75 / 81
页数:7
相关论文
共 25 条
[1]  
Aimukhamedova G. B., 1984, PROPERTIES USE PECTI, P61
[2]  
Bekturov E. A., 1982, POLYM COMPLEXES CATA
[3]  
BEKTUROV EA, 1990, J MACROMOL SCI R M C, VC30, P233
[4]   PHYSICOCHEMICAL PROPERTIES OF PECTIC ACID .1. THERMODYNAMIC EVIDENCE OF A PH-INDUCED CONFORMATIONAL TRANSITION IN AQUEOUS-SOLUTION [J].
CESARO, A ;
CIANA, A ;
DELBEN, F ;
MANZINI, G ;
PAOLETTI, S .
BIOPOLYMERS, 1982, 21 (02) :431-449
[5]  
DAVIDOVA SL, 1975, COORDINATION CHEM RE, V16, P195
[6]  
Fishman ML, 1986, CHEM FUNCTION PECTIN
[7]  
Fogarty W. M., 1974, Progress in Industrial Microbiology, V13, P59
[8]   IONIC-DIFFUSION THROUGH NITELLA CELL-WALL IN PRESENCE OF CALCIUM [J].
GILLET, C ;
LEFEBVRE, J .
JOURNAL OF EXPERIMENTAL BOTANY, 1978, 29 (112) :1155-1159
[9]  
HARTLEY FR, 1983, SOLUTION EQUILIBRIA, P114
[10]  
INTSEDY I, 1979, APPLICATION COMPLEXE, P68