▎ 摘　　要

NOVELTY - The initiator is claimed. The initiator is prepared by soaking soluble salt of iron element on carrier according to the mass ratio of iron element to the carrier, filtering to obtain an initiator precursor, drying the initiator precursor, calcining and activating to obtain the initiator, where the initiator precursor includes iron element and carrier, the mass ratio between iron element and carrier is 5-30%:70-95%, and the carrier includes activated carbon, molecular sieve, silicon dioxide, silicon carbide, graphite and/or graphene. USE - The initiator is useful for preparing hydrochlorocarbon or hydrochlorofluorocarbon by halogenated olefins and halogenated alkanes, preparing hydrofluoroolefins by gas-phase continuous reaction, and preparing E-1,3,3,3-tetrafluoropropene and Z-1,3,3,3-tetrafluoropropene (all claimed). ADVANTAGE - The method has easily available raw materials, high one-way product yield, no liquid waste and solid waste, and ensures continuous zero-pollution gas-phase production. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: Fluorination catalyst for preparing hydrochlorocarbon or hydrochlorofluorocarbon by halogenated olefins and halogenated alkanes, where the fluorination catalyst is prepared by mixing trivalent chromium compound and tungstate uniformly according to the mass ratio, pressing and forming to obtain a fluorination catalyst precursor, drying the fluorination catalyst precursor, calcining and activating to obtain the fluorination catalyst, and the fluorination catalyst precursor is composed of trivalent chromium compound and tungstate in a mass ratio of 70-99%:1-30%; Use of initiator and fluorination catalyst in preparing hydrofluoroolefins by gas-phase continuous reaction; and Preparing E-1,3,3,3-tetrafluoropropene and Z-1,3,3,3-tetrafluoropropene, comprising reacting halogenated olefins and halogenated alkanes in the presence of the initiators to obtain chloro-fluro complex (CClFCHCClF) (I), reacting it with hydrogen fluoride in the presence of the fluorination catalyst to obtain 1-chloro-1,3,3,3-tetrafluoropropene, and reacting it with hydrogen in the presence of a hydrogenation catalyst to obtain E-1,3,3,3-tetrafluoropropene and Z-1,3,3 ,3-tetrafluoropropene.mn2xy m and x = 1-3; and n and y = 0-2. Provided that: m+n=3; x+y=3.