Mass Deacidification of Archival Materials: The Battelle and Dez Process Compared

Deacidification for the conservation and preservation of paper-based works: A review

“…This system uses magnesium ethoxide as its primary component, in a complex with titanium alkoxides (both ethoxide and isopropoxide), which act as surfactants to dissolve the magnesium ethoxide in hexamethyldisiloxane (HMDO). Being fully soluble in HMDO, there is no need to add any alcohols as co-solvents into the system, which reduces the likelihood of media bleeding (Schwerdt 1989;Wittekind 1994;Wittekind et al 1994;Liers and Schwerdt 1995;Havermans et al 1996;Theune et al 1996;Dufour and Havermans 2001;Lichtblau and Anders 2006). The full complex formulation is referred to as magnesium ethoxide titanium ethoxide (METE), in which the ratio of magnesium to titanium is approximately 1:1.…”

“…To begin the process, the books are pre-dried for two days in vacuum, during which they are gradually warmed to 60°C (Havermans et al 1996;Lichtblau and Anders 2006). The normal equilibrium moisture content of the books is thereby lowered from the general 5-7 % (w/w) to less than 0.5%.…”

“…Observations Theune et al 1996 Uniform distribution of the alkaline product in treated paper, improved mechanical properties (with the exception of folding endurance) relative to the control after accelerated aging Havermans et al 1996 Final pH of about 9.3, remaning stable even after artificial aging. Residual odor observed in 42 of 49 tested books, discoloration noted on 8 books, bleeding on 4 books, white deposits on 1 book.…”

“…In 1995, improvements were made to the fluid dynamics of the treatment process, meaning the concentration of magnesium oxide in the suspension could be decreased by 50%, while maintaining a sufficient alkaline reserve (Porck 1996). This development reduced the problem of white deposits on the treated paper and book covers; these issues had been noted particularly on coated papers (Pauk 1996). Further improvements included a reduction in the MgO particle size.…”

Study of the Photo-Oxidation of Mass-Deacidified Papers

“…After drying, the documents are reconditioned for 3 weeks in a well-ventilated storage room to restore the normal water content and diminishing the characteristic odour of ethanol produced during the treatment 10 . After drying, the documents are reconditioned for 3 weeks in a well-ventilated storage room to restore the normal water content and diminishing the characteristic odour of ethanol produced during the treatment 10 .…”