Wood composites and processes to modify same using stable, low pH aqueous silicate suspensions

A stable, low pH aqueous silicate suspension for impregnating a wood article, the suspension comprising:

• a metal silicate having a solution concentration of from about 1.5 wt % to about 52 wt % and characterized by a modulus of from about 1.8 to about 4.0 and at least one of a protic acid solution and a buffering acid solution in an amount effective to acidify the metal silicate to a pH of about 3.0 or less;
• and
• a multivalent metal salt having a solution concentration from about 5 wt % to about 30 wt %;
• wherein the metal silicate includes a metal counterion selected from sodium, potassium, lithium, and combinations thereof;
• wherein the suspension has a pH of about 3.0 or less;
• and
• wherein the wood article has a depth of impregnation greater than that of a comparative wood article impregnated with the metal silicate alone, the depth of impregnation determined by X-ray fluorescence measurement of silicon based on a Forstner bit method, American Wood Protection Association Method A-51-1.