摘要
为探明保水剂与NH4+的相互作用,选用聚丙烯酸盐型保水剂(PAA)和聚丙烯酰胺型保水剂(P(AA-AM)),研究了保水剂在系列NH4Cl、NH4Cl-KCl、NH4Cl-CaCl2溶液体系中的吸水行为和对铵离子的吸附特征。结果表明:铵离子能显著降低保水剂的吸水倍率,并随铵离子浓度的增加,吸水倍率显著降低,相对吸水倍率与NH4+浓度之间具有显著的幂函数的减函数关系;NH4+、K+、Ca2+单一体系,NH4+-K+、NH4+-Ca2+共存体系对保水剂吸水倍率的影响按NH4+-K+<NH4+、K+<NH4+-Ca2+<Ca2+次序依次增强;虽然NH4+能显著降低保水剂的吸水倍率,但保水剂在吸水的同时也能大量吸附溶解于水中的NH4+,并随NH4+浓度的增加而增加,其吸附规律可用Freundlich吸附模型和线性吸附模型来表征;在不同溶液体系中,NH4+浓度相同时,保水剂对NH4+的吸附量差别很大,NH4+-K+或NH4+-Ca2+共存体系有利于NH4+吸附。NH4+单一体系、NH4+-K+、NH4+-Ca2+共存体系中,保水剂对NH4+的吸附量按NH4+<NH4+-Ca2+<NH4+-K+次序依次增大;P(AA-AM)的耐铵盐性和对NH4+的吸附能力均优于PAA。
In order to investigate the interaction between water retaining agents(WRAs)and NH4 +,polyacrylate(PAA) and poly acrylate-co-acrylamide(P(AA-AM))were selected as the tested WRAs to study the characteristics of water and NH4 + adsorption in a series of solutions of NH4 + Cl,NH4 + Cl-KCl and NH4 + Cl-CaCl2 respectively.The results showed that NH4 + could obviously reduce the water absorbency of the WARs.The water absorbency was markedly decreased with the NH4 + concentration increase.The relationship between relative water absorbency and NH4 + concentration could be described by the minus power function.For NH4 +,K +,Ca 2+ individual solution and NH4 +-K +,NH4 +-Ca 2+ coexistent solution,the influence of WRAs on water absorbency followed the order NH4 +-K + NH4 +、 K + NH4 +-Ca 2+ Ca 2.In despite of the sharply decrease of water absorbency with the rising of NH4 + concentration,WRAs could largely adsorb NH4 + and water.The adsorption capacity of NH4 + increased with rising of NH4 + concentration.This adsorption could be well described by Freundlich and linear model.In different solutions with the same NH4 + concentration,the adsorption capacities of NH4 + were different.NH4 +-K + and NH4 +-Ca 2+coexistent solutions were helpful to NH4 + adsorption.In NH4 +,K +,Ca 2+ individual solution and NH4 +-K +,NH4 +-Ca 2+ coexistent solutions,the adsorption capacity of NH4 + followed the trend of NH4 + NH4 +-Ca 2+ NH4 +-K +.Comparatively,P(AA-AM)was more tolerant to NH4 + andhad stronger adsorption capability for NH4 +than P(AA).
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2012年第7期117-123,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金(30971867
31172031)
广东省自然科学基金重点项目(10251022501000000)
广东省科技计划项目(2008B021000043)
教育部留学回国人员科研启动基金项目(教外司留[2009]1341号)
关键词
吸附
铵化合物
试验
保水剂
共存阳离子
absorption
ammonium compound
experiments water retaining agent
coexisting cation