响应曲面法漂白紫胶真空干燥条件的优化

为得到漂白紫胶真空干燥的优化条件，研究了不同温度和压强条件下漂白紫胶产品的颜色指数和干燥时间，用响应曲面法(RSM)设计试验并建立了真空干燥方法的拟合方程。结果表明，预测值和实测值的一致性较好，所建立的数学模型可以用于描述漂白紫胶的真空干燥。通过优化得到了漂白紫胶真空干燥的最优条件：温度30℃，压强30kPa，可以得到颜色指数为1.0 的漂白紫胶，其指标符合国家精制漂白紫胶1 级标准；温度50℃，压强30kPa，可以得到颜色指数为1.4 的漂白紫胶，其指标符合国家精制漂白紫胶2 级标准。同时对此条件进行了验证，结果表明这两种条件下制得的漂白紫胶符合国家标准，可以为生产提供参考。

Response Surface Methodological Approach to Optimizing Vacuum Drying Conditions of Bleached Shellac

Vacuum drying was applied to dry bleached shellac instead of normal temperature drying which has an outstanding disadvantage of low production efficiency dry. Response surface methodology (RSM) based on a three-level, two-variable central composite rotatable design (CCRD) was employed to evaluate the interactive effects of vacuum drying temperature and pressure on color index of bleached shellac and required drying time and two mathematical models were established for them as a function of vacuum drying temperature and pressure. The observed responses were in close agreement with the predicted values. This demonstrated the reliability of the two models in describing the vacuum drying of bleached shellac. The 8.48 h drying at 30 ℃ and 30 kPa resulted in a color index of bleached shellac of 1.0, and the bleached shellac product reached the first grade of the Chinese national standard; after drying at 50 ℃ and 30 kPa for 7.20 h, a product with a color index of 1.4 was obtained, which reached the second grade.