The phosphate ore flotation slurry process requires the addition of H₂SO₄ as a pH adjuster; this can cause the Ca²⁺ on the mineral surface to dissolve and combine with SO₄²⁻ to form CaSO₄, thereby changing the surface properties of dolomite. In this study, the effects of Ca²⁺ dissolution and CaSO₄ upon the surface properties of dolomite in a phosphate ore flotation slurry system were investigated. The results show that under the same conditions and different pH adjusters, the dissolution of Ca²⁺ in the phosphate ore slurry varies in the order H₂SO₄ > HNO₃ > HCl, increasing and then decreasing with increasing slurry preparation time. Under the same conditions, the maximum Ca²⁺ concentrations in fluorapatite, dolomite, and calcite slurry were 0.036, 0.020, and 0.037 mol/L, respectively. Surface tension and contact angle experiments showed that Ca²⁺ increases the surface tension of the sodium oleate (C₁₈H₃₃NaO₂) solution, which hinders foaming. CaSO₄ decreases the contact angle of the dolomite surface. Solution chemistry calculations, zeta potential measurements, and X-ray photoelectron spectroscopy (XPS) analysis show that the dissolved Ca²⁺ partly produces adsorbed CaSO₄ on the dolomite surface, and the Ca²⁺ reacts with oleate to form calcium oleate; both methods together inhibit the hydrophobicity of the dolomite surface.

磷矿浮选浆液工艺需要加入H ₂ SO ₄作为pH调节剂；这可使矿物表面的Ca ^{2+溶解并与SO} ₄ ^2-结合形成CaSO ₄，从而改变白云石的表面性质。本研究研究了Ca ²⁺溶解和CaSO ₄对磷矿浮选浆液体系中白云石表面性质的影响。结果表明，在相同条件和不同pH调节剂下，Ca ²⁺在磷矿浆液中的溶解度变化规律为H ₂ SO ₄  > HNO _{3 。} > HCl，随着浆料制备时间的增加而增加，然后减少。在相同条件下，氟磷灰石、白云石和方解石浆液中的最大Ca ²⁺浓度分别为0.036、0.020和0.037 mol/L。表面张力和接触角实验表明，Ca ²⁺增加了油酸钠（C ₁₈ H ₃₃ NaO ₂）溶液的表面张力，阻碍了起泡。CaSO ₄降低了白云石表面的接触角。溶液化学计算、zeta 电位测量和 X 射线光电子能谱 (XPS) 分析表明，溶解的 Ca ²⁺部分产生吸附的 CaSO ₄在白云石表面，Ca ²⁺与油酸反应生成油酸钙；这两种方法共同抑制了白云石表面的疏水性。