Simple and convenient method for producing high-purity ortho-formate

The invention provides a simple and convenient method for producing high-purity ortho-formate by using acrylonitrile byproduct hydrocyanic acid. The method comprises the following steps: firstly producing amine salt from the acrylonitrile byproduct hydrocyanic acid, fatty alcohol and hydrogen chloride, subsequently performing alcoholysis reaction on the presence of corresponding fatty alcohol so as to obtain an ortho-formate reaction liquid, adding a proper amount of an alkali substance in the generated ortho-formate reaction liquid, decomposing nitrogenous impurity compounds such as byproduct 1,3,5-s-triazine at certain temperature, wherein the decomposed product is nitrogen and solid formate with low boiling point, performing aftertreatment on the reaction liquid so as to obtain the high-purity ortho-formate through normal distillation. Therefore, the purpose of producing the high-purity ortho-formate with high yield is achieved.