Mineralization Simulation Of Guano Layer Apatite In Alcohol Gel System And Preparation Of A New Stone Conservation Materials Research

On the basis of mineralization mechanism of guano layer cellophane, and the sol - gelatin law that usually the high chemical activity material is selected during the procedure, this research uses ethylene glycol solution of CaO and P₂O₅ in ethanol solution as precursors. The whole mineralization is guided by the activity OH^- group spread around on rock surface, accelerating core forming speed and leading crystal chooses to grow in a particular direction. All a word, a new method was researched for preparing the hydroxyl apatite under the normal temperature and atmospheric pressure condition (HA).Since the guano layer apatite contains silicon, a small amount of TEOS is introduced in preparation of the sol. Thereby, the diffraction peaks of XRD spectra become more acute. SEM-EDAX analysis shows that the introduction of TEOS improved binding degree between calcium phosphate and the white marble stone.At the same time, the reinforce simulation experiments of deterioration stone are carried out. After the protection of the principal components, conductivity analysis shows that this film can sustain pH = 3≈4 hydrochloric acid erosion, the reinforcement was enhanced 8.5 times compared to the blank by the means of compressive strength and the water contact angle was basically unchanged. This study also considered other factors on the reinforcement strength, permeability and other indicators.Finally, in order to be closer to practical applications, this work also includes some field experiments. The preparation process of protection of material is carried out under normal temperature and pressure conditions, without adjusting pH, operated simply, suitable for large-scale operations. Tracking observations during one year indicate that related protection of materials in experiment generates a layer of phosphate protective film on calcium carbonate rock basis.This work had tried to research the possibility of preparing the protection material of lithical basis in the alcosol system for the first time, and basically resolve three big shortcomings of inorganic protection materials, which are the soluble salt problem, reinforcement strength problem and permeability. At the same time, this work has originally designed quantitative evaluation method—the electric conductance test acid resistant effect, changed the current situation that formerly in the lithical cultural relic acid resistance appraisal often relying on the subjective observation.Anyway, this work has provided ideas to develop the new protection material for stone cultural relics, building material as well as rock body.