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In building ceramics production process, the dispersion agent is added in an effective dispersion of the ceramic particles contribute to and in the case of high solids to maintain good fluidity. Dispersant can effectively improve the quality of the ceramic slurry and grinding efficiency, reduce water and energy consumption. Currently, construction ceramics mainly inorganic dispersant based, its stability and ceramic slurry grinding effect is not ideal. Polymer dispersant ceramic slurry to meet the needs of good dispersion stability, but its price is high and its application is limited. This paper systematically studied a series of polymeric dispersant on the performance of building ceramic slurry, and through chemical modification and physical complex method was developed based ceramics lignin dispersant. Main research progress and results are as follows: (1) a series of systematic study of architectural ceramics polymer dispersant slurry solids, flow time and the apparent viscosity and other properties of the initial screening has good dispersion viscosity reduction effect naphthalene superplasticizer FDN, Dongguan efficient dispersant GCL4-1, amino acid series superplasticizer ASP and lignin-modified amino acid series ASL four kinds of dispersants. However, a single use of these polymeric dispersant, its architectural ceramic slurry dispersion is less than the commonly used dispersant control sample (STPP - sodium silicate). (2), respectively, and the four kinds of inorganic dispersant compatibility, get two kinds of composite dispersant viscosity reduction effect and dispersion stability are superior to the commonly used dispersant control sample. The first one is ASP and H, S compatibility resulting composite dispersant. When the ASP and H, S mass ratio of 1.0:1.0:5.0, a solids content of 69% and ash 0.35%, the flow time of 45.12s, powders reference sample score shortened 13.32s. The second is the ASL and T, S compatibility resulting composite dispersant. When the ASL and T, S mass ratio of 1.0:0.8:5.0, a solids content of 69% and ash 0.34%, the flow time of 53.50s, powders reference sample score shortened 4.94s. Mixed with dispersants ASP-HS, ASL-TS and contrast like the apparent viscosity of the slurry dispersant were 240.0 mpa.s, 246.5 mpa.s and 288.5 mpa.s; settling time 120min, the dispersion stability index were 3.32, 3.39 and 3.95; particle sedimentation particle size were 17.25μm, 16.34μm and 16.27μm. (3) the test results show that the composite dispersant ASP-HS, ASL-TS grinding effect than the control sample. Doping control sample milled slurry through a 250 mesh sieve 7h later than 1.02%, doped sample ASP-HS and ASL-TS 7h and 6h after the ball, over 250 mesh sieve were 0.30% and 1.04%; doped three kinds dispersant flexural strength of the ceramic tiles or less, respectively, 2.53 MPa, 2.48 MPa and 2.67 MPa. (4) In order to reduce the production cost of the dispersant compound and improving the dispersion properties of phenol instead of part of the introduction of the alkali lignin with the amino benzene sulfonate and phenol condensation, process optimization, synthesis of novel lignin dispersant LMA. The optimal reaction conditions LMA is n (A): n (P): n (L): n (F) = 1.00: 0.90:1.26:2.50, wherein the alkali lignin alternative place of phenol was 70%, the reaction solution The optimum pH value of about 10.4, 95 ℃ condensation time was 3.0h, and the reaction was controlled at the concentration of 25wt% ~ 33wt%. By infrared spectra provable modified LMA introduced alkali lignin. (5) The surface tension of the aqueous solution of the LMA, the ceramic particles in the adsorption capacity and adsorption properties of its salt. LMA can reduce the surface tension of water to 49.92 mN.m -1 , the surface of the ceramic particles in the adsorption capacity of 1.1mg.g -1 . When T and the LMA mass ratio of 1:1, the surface tension of the aqueous solution can be reduced to 46.51mN.m -1 , due to the addition salts compete with the LMA adsorption, adsorption capacity decreased to such 0.4 mg.g -1 , and the more the amount of salt, LMA of the ceramic particles is less saturated adsorption amount. (6) The LMA and T, S lignin-based ceramic compound obtained dispersant LMA-TS, systematic study of its impact on the performance of building ceramic slurry. Solid content of 69%, the lignin-based ceramics doped LMA-TS dispersant slurry outflow time of 49.53s, shorter than the comparative sample 7.08s. Its ceramic grinding, dispersion stability was better than the control sample. After milling blank and contrast kind of ceramic particle size were 19.47μm, 13.45μm, while doped LMA-TS particle diameter of only 12.61μm. Doped LMA-TS slurry dispersion stability index 120min when 2.5, 3.0 less than the control sample slurry; in 60min, the doped LMA-TS slurry particle sedimentation particle size of 15.37μm, less than the control sample slurry 16.29μm. Doped LMA-TS ceramic particles is higher than the overall surface of the Zeta potential of doped control sample, especially when the dosage of 0.35wt%, its Zeta potential has reached 38.89mv, than the comparative sample doped high Zeta potential is 6.0 mv . 1,000 magnification of the microscope further proof of the sample doped LMA-TS than control sample dispersion. As can be seen from the flow curve, doped LMA-TS slurry viscosity reduction effect is better in nearly 70wt% solids content, the intrinsic viscosity of 232.3 mpa.s.
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