NOVELTY - Preparing (P1) silane in columnar reaction vessel, where vessel containing lower inlet and outlet, upper inlet and outlet and having reaction mixture, involves: introducing hydride feed (7) comprising hydride into upper inlet of vessel; introducing feed gas (3) comprising halosilane into lower inlet of vessel to bubble feed gas through the reaction mixture, where the hydride reacting with halosilane to produce silane and halide salt; discharging product gas (19) comprising silane from upper outlet; and discharging effluent comprising the halide salt from lower outlet.    USE - For preparing silane in a columnar reaction vessel (claimed). The silane is useful in semiconductor industry, for deposition of an epitaxial silicon layer on semiconductor wafers and for production of polycrystalline silicon, which is a vital raw material used to produce many commercial products including integrated circuits and photovoltaic (i.e. solar) cells.    ADVANTAGE - The process for preparing silane, is economical process for producing silane; and can relatively improve reactor productivity and conversion of the various reactants, where the conversion of the hydride is at least 80 (preferably at least 99)%; and the conversion of halosilane is at least 80 (preferably at least 99)%.    DETAILED DESCRIPTION - Preparing (P1) silane in a columnar reaction vessel, where the vessel containing a lower inlet, a lower outlet, an upper inlet and an upper outlet and having a reaction mixture in it, involves: introducing a hydride feed (7) comprising a hydride into the upper inlet of the reaction vessel; introducing a feed gas (3) comprising a halosilane into the lower inlet of the reaction vessel to bubble the feed gas through the reaction mixture, where the hydride reacting with the halosilane to produce silane and a halide salt; discharging a product gas (19) comprising silane from the upper outlet; and discharging an effluent comprising the halide salt from the lower outlet. An INDEPENDENT CLAIM is included for preparing (P2) silane in a reaction vessel (V2) having a reaction mixture in it, where the vessel having at least one baffle (30), the baffles creating at least two reaction zones (35, 37) connected in series, involving: introducing the hydride feed comprising the hydride into the reaction vessel; introducing the feed gas comprising the halosilane into the reaction vessel to bubble the feed gas through the reaction mixture, where the hydride reacting with the halosilane to produce silane and the halide salt; discharging the product gas comprising silane from the reaction vessel; discharging the effluent comprising the halide salt from the reaction vessel; and agitating the reaction mixture.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic of the reaction vessel having three reaction zones for producing silane which shows reactant and product flows to and from the reaction vessel.    Feed gas (3)    Hydride feed (7)    Product gas (19)    Baffle (30)    Reaction zones (35, 37)