改良胶溶法制备氢氧化铁胶体的条件优化与性质表征  

Optimization of preparation and characterization of Fe(OH)_(3)colloid prepared by improved colloidal method

作　　者：司承运 刘子凡 潘胜强 肖湉 杨弈 黄嘉琪 辛思源 张正华 徐开俊 SI Chengyun;LIU Zifan;PAN Shengqiang;XIAO Tian;YANG Yi;HUANG Jiaqi;XIN Siyuan;ZHANG Zhenghua;XU Kaijun(School of Science,China Pharmaceutical University,211198,Nanjing,Jiangsu,PRC)

机构地区：[1]中国药科大学理学院,江苏省南京市211198

出　　处：《曲阜师范大学学报（自然科学版）》2023年第1期120-128,共9页Journal of Qufu Normal University(Natural Science)

基　　金：大学生创新创业训练计划项目(202010316210).

摘　　要：为进一步优化本科物理化学实验“Fe(OH)_(3)胶体的制备与表征”,在改良胶溶法的基础上建立L_(31)(5^(5))正交试验,探究了HCl用量、离心操作(离心转速、离心时间、离心后取样高度)等因素对所制备Fe(OH)_(3)胶体粒径分布、ζ-电位等的影响.研究发现:离心并分段取样表征的操作可有效分离不同尺寸的胶体并降低胶体的分散程度;随着HCl用量增加,成胶原理经历传统碱式胶溶法-改良胶溶法-水解法变化过程,并阐明改良胶溶法下胶体的形成机理为酸性环境下H^(+)、Cl^(-)共同影响达到平衡的缓冲体系胶体形态.该文还进一步优化了Fe(OH)_(3)胶体的制备与后处理条件:HCl用量7.5~9 mmol(约为Fe(OH)_(3)当量的1~1.2倍)、离心转速约8000 rpm(最大离心力约8890×g)、离心时间5~10 min、取样高度2~3 cm,以及稀释10倍并超声助分散操作.结果表明该条件下实验所得胶体均一性高、性质稳定,验证实验测得粒径24.18 nm(RSD<1.4%),电位33.43 mV(RSD<8.0%),电导率0.223 S/m(RSD<5.2%).An analytical methodology for quantitatively exploring colloidal properties was established to further optimize the undergraduate physical chemistry experiment“Preparation and Characterization of Fe(OH)_(3) colloid”.L _(31)(5^(5))orthogonal design was established on the basis of the improved colloidal solution method.The effects of HCl dosage,centrifugal operation(centrifugal speed,centrifugal time and sampling height after centrifugation)on the particle size distribution andζ-potential of Fe(OH)_(3) colloid prepared were investigated.It is found that the operation of centrifugation and segmented sampling characterization can effectively distinguish colloids of different sizes and reduce the dispersion of colloids.And with increase of HCl dosage,colloid formation experienced the change process of traditional basic colloidal chemical method—improved acidic colloidal chemical method—hydrolysis method.The formation mechanism of the improved colloidal method was that H+and Cl-jointly affected the colloidal morphology of buffer system to achieve equilibrium in acidic environment.In addition,the preparation and post-treatment parameters of Fe(OH)_(3) colloid were further optimized:the dosage of hydrochloric acid was 7.5~9 mmol(about 1~1.2 times the equivalent of Fe(OH)_(3)),the centrifugal speed was about 8000 rpm(the maximum centrifugal force was about 8890×g)Centrifugation time 5~10 min,sampling height 2~3 cm,dilution 10 times and ultrasonic assisted dispersion operation.Under this condition,the colloid obtained has high homogeneity and stable properties.The particle size is 24.18 nm(RSD<1.4%),the potential is 33.43 mV(RSD<8.0%),and the conductivity is 0.223 S/m(RSD<5.2%).

关 键 词：氢氧化铁胶体 粒径 ζ-电位 正交试验 改良胶溶法 

分 类 号：O6-3[理学—化学]