摘要
选择性絮凝分选是微细粒矿物高效分选的重要手段之一.为了强化絮凝剂在亲水、疏水矿物表面的絮凝选择性,将疏水基团十六烷基二甲基烯丙基氯化铵(C16DMAAC)引入聚丙烯酰胺(PAM)分子链中合成了疏水改性聚丙烯酰胺(HMPAM),采用耗散型石英晶体微天平(QCM-D)研究了不同浓度K^(+)和Ca^(2+)对分散剂六偏磷酸钠(SHMP)和HMPAM在亲水和疏水化表面原位吸附行为的影响,并使用激光粒度分析仪分析了不同盐度下SHMP和HMPAM对硅微粉及疏水改性硅微粉粒径分布的影响.结果表明,不同盐度环境下HMPAM均呈现了较好的絮凝选择性.背景溶液分别为10 mmol·L^(-1)、100 mmol·L^(-1)KCl及1 mmol·L^(-1)CaCl_(2)时,QCM-D结果表明SHMP在疏水化表面均未形成吸附层,随后HMPAM在疏水化表面发生吸附,且随着盐度的增加,HMPAM的吸附量增大且吸附层的耗散性降低;背景溶液为10 mmol·L^(-1)CaCl_(2)时,SHMP也未抑制HMPAM在疏水化表面的吸附,形成了谐振频率变化(Δf)为-18.3 Hz的吸附层.相比,100 mmol·L^(-1)KCl时1 mmol·L^(-1)SHMP在SiO_(2)表面形成薄而致密的吸附层,随后抑制了HMPAM的吸附;10 mmol·L^(-1)CaCl_(2)中SHMP在SiO_(2)表面形成耗散的吸附层,随后10 mmol·L^(-1)CaCl_(2)冲洗过程中沉积了较为致密的吸附层,也抑制了HMPAM吸附.不同盐度下SHMP和HMPAM对硅微粉及疏水化硅微粉粒径分布的影响与QCMD试验结果相一致.本研究是选择性絮凝分选中絮凝剂选择与研发的重要研究基础.
Selective flocculation separation is one of the most efficient methods for fine mineral separation.To enhance the flocculation selectivity on the surfaces of hydrophilic and hydrophobic minerals,a hydrophobic group such as cetyldimethyl allyl ammonium chloride(C16DMAAC)was introduced within the molecular chain of polyacrylamide(PAM)to synthesize hydrophobically modified polyacrylamide(HMPAM).The effects of different K^(+)and Ca^(2+)concentrations on the in situ adsorption behavior of dispersants such as sodium hexametaphosphate(SHMP)and HMPAM and their effect on hydrophilic and hydrophobic surfaces were studied using dissipative quartz crystal microbalance(QCM-D).The effects of SHMP and HMPAM on the particle size distribution of silicon powder and hydrophobically modified silicon powder with different salinity were analyzed using a laser particle size analyzer.Results indicated that HMPAM exhibited good flocculation selectivity at varying salinity concentrations.When the background solutions were 10 mmol·L^(-1)100 mmol·L^(-1)KCl,and 1 mmol·L^(-1)CaCl_(2),the QCM-D results indicated that no adsorption layer of SHMP was formed on the hydrophobic surface;moreover,the HMPAM was adsorbed on the hydrophobic surface in sequence.With an increase in salinity,the adsorption of HMPAM increased,and the dissipation of the adsorption layer decreased.Moreover,in the background solution of 10 mmol·L^(-1)CaCl_(2),SHMP did not inhibit the adsorption of HMPAM on hydrophobic surfaces,and an adsorption layer with the change of resonant frequency(Δf)of-18.3 Hz was formed.Conversely,a thin and dense adsorption layer of SHMP was generated on the surface of SiO_(2)in 100 mmol·L^(-1)KCl,which inhibited the adsorption of HMPAM.In 10 mmol·L^(-1)CaCl_(2),a dissipative adsorption layer of SHMP was detected on the surface of SiO_(2).Furthermore,a relatively dense adsorption layer was deposited after the injection of 10 mmol·L^(-1)CaCl_(2)solution,which also inhibited the adsorption of HMPAM.The results of floc size measurements reveale
作者
邹文杰
饶博
赵伟
徐瑞景
王廷
ZOU Wen-jie;RAO Bo;ZHAO Wei;XU Rui-jing;WANG Ting(School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China)
出处
《工程科学学报》
EI
CSCD
北大核心
2023年第4期533-540,共8页
Chinese Journal of Engineering
基金
国家自然科学基金资助项目(51604019)
中央高校基本科研业务费专项资金资助项目(FRF-IP-20-03)
国家重点研发计划重点专项资助项目(2020YFC1807804)。
关键词
疏水改性聚丙烯酰胺
石英晶体微天平
选择性絮凝
六偏磷酸钠
吸附行为
hydrophobic modified polyacrylamide
quartz crystal microbalance with dissipation
selective flocculation
sodium hexametaphosphate
adsorption behavior
