Cleaning aqueous

Aqueous and semi-aqueous cleaning systems, used for printed circuit boards and other industrial degreasing operations (Mandich and Krulik, 1992 Davis et al., 1994)... 

Phosphates and phosphonates are valuable contents of cleaners used for technical purposes especially when anticorrosive behavior is also required. Phosphoric acid esters are a component of aqueous cleaning compositions for printed circuit boards [212]. 

Aqueous cleaning, in which spraying of aqueous acidic or alkaline detergent solutions is followed by normal and deionized water rinses. Strong detergents dissolve greases, oils and possibly oxides. It is necessary to rinse thoroughly to avoid later attacks. 

The DWS applies an aqueous solution during a high-pressure spray cycle, followed by turbulent wash and rinse cycles. The aqueous cleaning solution is recovered and reconditioned for reuse concurrently with the debris cleaning process, reducing the quantity of process water required to clean the debris. 

Remove Sludge and Soils Promptly. Removing sludge and soils from aqueous cleaning soak tanks will reduce chemical use by increasing the permissible time interval between dumping and total cleanout of the tank. 

Figure 7 shows schematic reproductions of the shapes of the X-ray diffractive traces of alpaca observed after treatments in water and tetrachloroethylene. The reflections observed at about 9.8° (20) may indicate that the fibers contain ordered components having a specific helical configuration of the polypeptide chains (31). Aqueous treatments caused some changes in the intensities of the traces. In comparison, the nonaqueous treatment in tetrachloroethylene yielded a trace not much different from the control trace. On the basis of these observations, it is postulated that nonaqueous treatments affect the fiber morphology of historic cotton and protein fibers to a lesser degree than aqueous cleaning treatments. 

Design for ease of drying after aqueous-clean... 

Figure 6, Normalized annual costs for a S-year accounting life of the equipment. Comparison between an aqueous cleaning process and a supercritical (X>2 cleaning process.

Onsite recycling has lower costs and liabilities than offsite commercial recycling. For aqueous cleaning media, removal of solids bv sedimentation or fil-... 

The selection of an aqueous cleaning system is simplified if only water alone, or water and a commodity chemical alone, are used. The cleaning performance can be somewhat predicted based on solubility characteristics (at the appropriate pH) or by consideration of the peptizing performance of alkalinity on protein or the oxidizing action of sodium hypochlorite on denatured protein. In the case of formulated multifunctional cleaning agents, the performance is more... 

M. L. Kniffin, T. E. Beerling, and C. R. Helms, The effectiveness of aqueous cleaning for the removal of evaporation iron and copper from silicon surfaces, J. Electrochem. Soc. 139, 1195, 1992. 

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