Objective: To establish a optimum process for eliminating n-butyl alcohol in TianShu dropping pills and detect vestigial of n-butyl alcohol in intermediate of concentrated solution. Method :To use the orthogonal experimental design method and be taken as evaluating norms by vestigial of n-butyl alcohol

the analysis of vestigial of n-butyl alcohol was carried out on GC and optimized the conditions. Result: The optimal technique for eliminating n-butyl alcohol was 80 ℃ reduced-pressure distillation with three times. The solution add 0.25 times of water every time. The recovery of eliminating n-butyl alcohol was 101.13% with RSD of 1.10%. Conclusion: The optimal technique was convenient

efficient

accurate

reliable and with good replications.