不同类型酸对石灰岩的模拟腐蚀实验

SIMULATED CORROSION BY ACID RAIN ON CARBONATE STONE

硫酸和硝酸是酸雨中腐蚀石灰岩的主要成分,以不同pH值(4.0、5.6)和流量(6 mL.min-1、30 mL.min-1)的硫酸、硝酸及混酸溶液对石灰岩进行淋溶处理,通过测定溶液中pH值变化,Ca2+离子浓度变化,重量损失变化,研究酸类型对石灰岩腐蚀的影响.结果表明,酸雨对石灰岩的腐蚀是物理冲刷和化学溶蚀共同作用的结果,化学溶蚀主要受到H+和CO2浓度的控制;pH和酸雨流量是腐蚀程度的主要影响因素,总体来说阴离子对腐蚀影响不大.

Because sulphuric acid and nitric acid are the major components oI aclo ram responslnxe 1or corrosion, ot carbonate stone, it is possible to simulate the deterioration of stone inscriptions exposed to acid rain with dilute sulphuric acid, nitric acid and the mixed acid solution. The changes of pH value and Ca^2＋ concentration in the solution and loss of carbonate stone have been studied by washing carbonate stone samples with sulphuric acid, nitric acid and mixed acid solution at different pH （4. 0, 5.6） and different flow velocity （6 mL-min＆^-l, 30 mL. min^-1 ）. The results showed that the process of carbonate stone corrosion is a combination of physical scour and chemical dissolution, while the latter is mainly flow rate of the acid are essential factors that affect the negligible for corroding carbonate stone. controlled by H^＋and C02. The pH value and the extent of corrosion. The total effect of anions is