Effect of dispersant on the slurry ability of semi-coke water slurry and its adsorption kinetics
姚雅倩杨志远孟茁越李银艳朱翰博
YAO Yaqian,YANG Zhiyuan,MEMG Zhuoyue,LI Yinyan,ZHU Hanbo
西安科技大学化学与化工学院国土资源部煤炭资源勘查与综合利用重点实验室
为解决我国兰炭资源浪费的问题,采用兰炭粉代替原煤制备兰炭浆,不仅可缓解石油需求压力,还为兰炭粉利用提供了一条新途径。利用神府兰炭粉及5种不同分散剂(亚甲基双萘磺酸钠NNO、木质素磺酸钠SLS、腐植酸钠SH、聚羧酸盐PCE、复配型阴离子-阴离子NNO/PCE)为原料,研究了由兰炭粉制的兰炭浆对阴离子分散剂的性能、吸附机理及吸附动力学的影响。研究了每种分散剂制备兰炭浆的流变行为,添加不同分散剂的兰炭浆都表现出假塑性流体特征;加入NNO/PCE分散剂制备的兰炭浆,剪切速率100 s-1时的表观黏度仅为359.3 mPa·s,且析水率小无硬沉淀,使用NNO为分散剂时虽流动性好,但稳定性差且析水率最大。对添加不同分散剂的兰炭粉进行红外光谱测试,发现添加分散剂可以改变兰炭粉表面的亲疏水性。吸附试验结果显示,NNO、SLS、SH、PCE、NNO/PCE分别在60、60、120、240和240 min达到吸附平衡;吸附量排序为NNO/PCE(8.796 mg/g)>PCE(7.977 mg/g)>SH(6.845 mg/g)>SLS(3.718 mg/g)>NNO(1.029 mg/g);准二级速率方程能够较好描述分散剂在兰炭表面的吸附动力学过程。最后提出了阴离子分散剂的吸附机理模型,结果表明,阴离子分散剂在兰炭浆中的吸附作用主要归因于兰炭颗粒中静电斥力的增强。
In order to solve the problem of the waste of semi-coke resources in China, the preparation of semi-coke water slurry with semi-coke powder instead of raw coal can not only alleviate the pressure of oil demand, but also provide a new way for the utilization of semi-coke powder. In this paper, the properties, adsorption mechanism and adsorption kinetics of anionic dispersants were studied by-using Shenfu semi-coke powder and five different dispersants (methylene dinaphthalene sulfonate NNO, sodium lignosulfonate SLS, sodium humate SH, polycarboxylate PCE, complex anion-anion NNO/PCE). The rheological behavior of semi-coke water slurry prepared with each dispersant was studied. The semi-coke water slurry with different dispersants shows pseudoplastic fluid characteristics. When NNO/PCE dispersant is added, the apparent viscosity of the slurry is only 359.3 mPa·s at the shear rate of 100 s-1, and the water separation rate is small without hard precipitation. When NNO is used as dispersant, the fluidity is good, but the stability is poor and the water separation rate is the largest. Through the infrared spectrum test of the semi-coke particle with different dispersants, it is found that the addition of dispersants could change the hydrophilicity and hydrophobicity of the semi-coke particle surface.The adsorption test results show that NNO, SLS, SH, PCE and NNO/PCE reach the adsorption equilibrium at 60,60,120,240 and 240 min, respectively. The increasing trend of adsorption capacity is NNO/PCE (8.796 mg/g)>PCE(7.977 mg/g)>SH(6.845 mg/g)>SLS(3.718 mg/g)>NNO(1.029 mg/g). The pseudo-second-order rate equation can well describe the adsorption kinetics of dispersant on the surface of semi-coke. Finally, the adsorption mechanism model of anionic dispersants was proposed. The results show that the adsorption of anionic dispersants in semi-coke water slurry is mainly due to the enhancement of electrostatic repulsion in semi-coke particles.
兰炭浆分散剂流变性稳定性吸附动力学吸附机理
semi-coke water slurry;dispersant;rheology;stability;adsorption kinetics;adsorption mechanism
0 引言
1 试验
1.1 试验原料与仪器
1.2 兰炭浆的制备及性能测试
1.3 吸附性能测试
2 试验结果与讨论
2.1 分散剂对兰炭浆流变性能的影响
2.2 分散剂对兰炭浆稳定性的影响
2.3 分散剂在兰炭粉表面的吸附性能
3 吸附机理
4 结论
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会