NOVELTY - Composite solid alkali catalyst comprising 100 pts. wt. gamma -aluminum oxide, 0.5-5 pts. wt. bonding agent, 1-25 pts. wt. magnesium containing compound, 1-25 pts. wt. calcium containing compound, 0.5-5 pts. wt. polyacrylamide and 0.1-2 pts. wt. inorganic alkali, is new. The bonding agent is glycerin, starch, methyl cellulose, polypropylene, aluminum or water glass. The magnesium containing compound is magnesium oxide, magnesium hydroxide, magnesium carbonate, magnesium acetate or magnesium chloride.    USE - The composite solid alkali catalyst is useful for preparing guaiacol glyceryl ether (claimed).    ADVANTAGE - The composite solid alkali catalyst can be simply prepared with high yield in an eco-friendly and less energy consuming manner.    DETAILED DESCRIPTION - Composite solid alkali catalyst comprising 100 pts. wt. gamma -aluminum oxide, 0.5-5 pts. wt. bonding agent, 1-25 pts. wt. magnesium containing compound, 1-25 pts. wt. calcium containing compound, 0.5-5 pts. wt. polyacrylamide and 0.1-2 pts. wt. inorganic alkali, is new. The bonding agent is glycerin, starch, methyl cellulose, polypropylene, aluminum or water glass. The magnesium containing compound is magnesium oxide, magnesium hydroxide, magnesium carbonate, magnesium acetate or magnesium chloride. The calcium containing compound is calcium oxide, calcium hydroxide, calcium carbonate or calcium chloride. The inorganic alkali is sodium hydroxide, potassium hydroxide, sodium carbonate or potassium carbonate. INDEPENDENT CLAIMS are included for:    (1) the preparation of the composite solid alkali catalyst; and    (2) use of the composite solid alkali catalyst for preparing guaiacol glycerol ether comprising dissolving catechol as a raw material, allyl halide and halogenated alkyl in a solvent, uniformly mixing to obtain a mixed solution, reacting benzene-1,2-diol with a butane compound of formula (XCH2-CH-CH2) (I) to give a 2-((Z)-but-2-enoxy)phenol compound of formula (II), adding the mixed solution and an aqueous solution of potassium permanganate to (II), uniformly mixing, separating the mixture, reacting the separated mixture with 1-allyloxy-2-methoxy-benzene, and stirring, where the solvent is tetrahydrofuran, acetone, acetonitrile, N,N-dimethylformamide, N,N-dimethylacetamide or 2-methyl dioxane.