Synthesis Of Acylation Sulfonic Acid Phenolic Resin Comb Dispersant And Preparation Of Coal Water Slurry

Shenfu coal,a low-rank coal,contains more oxygen-containing functional groups and pores.Since a large amount of water is adsorbed by oxygen-containing functional groups,that is,the amount of free water in the system is small,and a large amount exists in the form of adsorbed water.Therefore,it is difficult to produce high concentration and good fluidity coal-water slurry.According to the basic properties of coal samples,this paper should design the coal-water slurry dispersant of this coal type,and introduce the corresponding functional groups in a targeted manner.Through single factor and orthogonal experiments,the synthesis process can be optimized and synthesized to obtain the excellent coal water slurry dispersant.According to the characteristics of coal quality,combined with the mechanism of action of the dispersant and the basis of design theory,the molecular structure of the dispersant was designed.The comb structure is advantageous for the molecular structure design and control,and the comb dispersant structure has better adsorption and dispersion effects than the linear dispersant structure.The structure is mainly composed of benzene ring,and hydrophilic sulfonic acid group is introduced.According to the nature of the coal,benzene ring functional group is introduced to achieve a high degree of matching with the condensed aromatic nucleus and tight binding.The experiment used phenol as the reaction raw material,concentrated sulfuric acid as the sulfonating agent,formaldehyde polymerization,and benzoyl chloride as the modifier.The optimum experimental conditions for the synthesis of dispersants were investigated by single factor and orthogonal experiments.The results showed that the sulfonation temperature was 100 ~oC,the sulfonation time was 2.5 h,the polymerization temperature was 95 ~oC,the polymerization time was 3 h,the acylation temperature was 100 ~oC,and the acylation time in 2.5 h was obtained.The dispersant synthesized works best.The influence of different kinds of dispersants on the slurry formation performance of coal water slurry was investigated.The effect of dispersant on slurry stability,fluidity and rheology was studied.The results show that when the amount of comb-type dispersant is 0.5%,the viscosity of the slurry is the highest.Compared with the dispersant of naphthalene and lignin,the stability of the slurry can reach the state of no water-out,and the flowability reaches the continuous flow state.Comprehensive evaluation is superior to other dispersantsDetermination of the zeta potential of the slurry and the adsorption performance.The zeta potential of the coal sample adsorption dispersant was measured by a microelectrophoresis instrument,and the isoelectric point of the solution was calculated to explain the stability mechanism of the slurry.The absorbance of Shenfu coal before and after adsorption of different concentrations of dispersant was measured,and the adsorption amount of coal surface was calculated by using the linear equation of concentration and absorbance.The experiment uses the simulation of the isotherm adsorption equation to judge the adsorption model of the dispersant.The results show that after three different kinds of dispersants are adsorbed by coal samples,the zeta potential of the system will decrease with the increase of pH,and the electronegativity will increase.At the same pH,the amount of dispersant is increased,the zeta potential of the system is lowered,and the electronegativity is enhanced.The absolute value of the zeta potential of the comb and lignin dispersant is larger than the absolute value of the zeta potential of the naphthalene dispersant,so the electronegativity is relatively strong.It shows that the dispersant is more tightly combined with the coal surface and the stability of the system is stronger.By analyzing the adsorption characteristics of the coal sample on the dispersant,it is judged that the Langmuir isotherm adsorption model is more in line with the adsorption of the dispersant by Shenfu coal.The are 25 figures,12 tables,and 74 references in the thesis...