氨基酸型木素鳌合树脂的制备

Preparation of amino-lignin chelate resins

以麦草Soda—AQ木素为原料，通过酚化，与氨基酸的Mannich反应以及核甲基化等一系列化学改性，制备了氨基酸型木素整会树脂。结果表明：（1）所制备的水煮衍生物具有良好的资合性，并对Cu^(2+)表现出选择性亲合力，最高资合容量达1．19mmol／g；（2）超滤法分离纯化的木煮，由于其纯度和平均分子量较高，比未经超滤的木素更易改性，所得螯合树脂螯合力更大；（3）通过Mannich反应引入木素的N－CH_2COOH和通过羧甲基化反应而引入的O－CH_2COOH是木素螯合树脂的螯合中心，二者比较，前者具有更高的螯合力，对Cu^(2+)的选择性更强。

As starting material, straw Soda-AQ lignin was subjected to the medffication involving acid cataiyzed phenolation, the Mannich reaction with amino acids and O-carboxmpethylation with chloroacetic acid. The resulting lignin chelate resins give an ion-binding capacity of 1.19 mmol/g for Cu2+. It is known that ultrakitrated lignin is more reaetive toward the modification than unultrafiltrated one due to higher purity and average molecular weight of the former. The N-CH2COOH introduced by Mannich reaction and O-CH2COOH introduced by carboxpoethytation are the centers binding metal ions in the lignin chelate resins. It is found that the former has greater ion-binding capacity and shows more preferential afffoity to Cu2+ than the latter.