Coagulation characteristics of humic acid modified with glucosamine or taurine.
Coagulation characteristics of humic acid modified with glucosamine or taurine.
复制标题
DOI：
10.1016/j.chemosphere.2007.04.012
复制
发表时间：
2007-09
期刊：
影响因子：
8.8
通讯作者：
M. Terashima;Shunitz Tanaka;M. Fukushima
中科院分区：
文献类型：
--
作者：
M. Terashima;Shunitz Tanaka;M. Fukushima
为了抑制腐殖酸（HA）在水溶液中的凝聚，用亲水性胺如氨基葡萄糖或牛磺酸对HA进行改性。这些胺通过酰胺键形成连接到HA中的羧基。改性程度（Rm）估计为21- 38%。改性HA的红外光谱也与酰胺键的存在一致。酸碱滴定结果表明，改性后HA样品的平均酸解离常数（pKapp）增加。HA的Ca ~（2+）结合能力随Rm值的增加而降低。临界pH值或Ca 2+浓度，在HA凝固发生，作为改性的结果增加。牛磺酸-HA的这些临界点高于葡糖胺-HA。这主要是由于牛磺酸中磺酸基的静电排斥。这些结果表明，HA的凝血被抑制修饰的分子与葡萄糖胺或牛磺酸。
To suppress the coagulation of humic acid (HA) in aqueous solutions, HA was modified with hydrophilic amines, such as glucosamine or taurine. These amines were attached to carboxyl groups in HA via amide bond formation. The degree of modification (Rm) was estimated to be 21–38%. Infrared spectra of the modified HAs were also consistent with the presence of amide bonds. Acid–base titration showed that the average acid-dissociation constant (pKapp) of the HA samples was increased by the modification. The Ca2+binding capacity of HA decreased with an increase in Rmvalue. Critical pH or Ca2+concentration, at which HA coagulation occurs, was increased as the result of the modification. These critical points for taurine-HA were higher than those for glucosamine-HA. This is mainly due to electrostatic repulsion by sulfonate groups in taurine. These results indicate that the coagulation of HA is suppressed by modifying the molecules with glucosamine or taurine.