Ideal Temperature for Cleaning

Question:
What is the ideal temperature for cleaning ultrasonically and spray washing?

Answer:
The Aqueous Cleaning Handbook, written by the technical support team at Alconox, discusses heat and cleaning applications on page 23.

In general, higher-temperature cleaning solutions result in better cleaning. In practice, there is typically an optimum temperature for a given combination of cleaning variables. Many soak, manual, and ultrasonic cleaning methods work best, for example, at 50°C to 55°C. Many spray washing techniques work best at 60°C to 70°C.

To request a copy of The Aqueous Cleaning Handbook, please visit this page.

pH of Tergazyme

Question:
Can you lower the pH of Tergazyme using Citric acid or vinegar?

Answer:
Yes. To adjust the pH of a 1% Tergazyme solution from pH 9.5 to about pH 8.5 add 0.1 grams of 99% anhydrous citric acid for each 5 grams of Tergazyme. To get to pH 8.0 add 0.2 oz of citric acid. White table vinegar that is typically 5-8% active by weight, use roughly 2 ounces of vinegar added to 4 gallons of 1% Tergazyme solution that has 5 ounces of Tergazyme in it to get about a pH 8.5 solution, and use roughly 4 ounces of vinegar to get a pH 8.0 solution. Use a calibrated pH meter with stirring to monitor additions.

To view the technical bulletin for Tergazyme, please download this PDF.

Defining Free Rinsing

Question:
What does free rinsing mean?

Answer:
Free rinsing means it will rinse away very easily or freely. It does not mean that you do not have to rinse. For example a non-free rinsing cleaner might contain fragrances that were designed to deposit and leave a fresh scent, or it might contain corrosion inhibitors that are designed to deposit and leave behind an anti-corrosion film. Alconox, Inc, cleaners are free rinsing and do not leave deposits on substrates after rinsing. More information on Alconox cleaners can be found by visiting www.alconox.com.

Removing Polishing Compound

Question:
What Alconox product is ideal for manual removal of polishing compound from aluminum?

Answer:
For manual cleaning use a warm 2% Citranox solution to remove the polishing compound. Citranox will not harm the mirror finish on the aluminum. Rinse thoroughly after washing.

For more information on Citranox, visit the Alconox website.

Rinsing

Question:
What is the proper way to rinse after using Alconox detergents?

Answer:
Running water rinse for at least 10 seconds on each surface is desirable. If that is not practical, use a series of three or more agitated soak rinse tanks or at least two counter-flow cascade rinse tanks. The quality of the rinse water is important for medical device and pharmaceutical cleaning applications. Tap water contains varying degrees of organic microbes, particulates, and hardness (calcium and magnesium salts). Rinsing with tap water and evaporating dry can deposit these contaminants leaving water spots. Using high purity water such as distilled water, deionized water, or RO (reverse osmosis) water are ideal for use.

To read more about rinsing, the Alconox Guide to Critical Cleaning is available in pdf format.

Cleaning Lidocaine and Dextrose

Question:
What Alconox brand cleaner would be best for cleaning Lidocaine and Dextrose?

Answer:
Lidocaine and Dextrose are water soluble 4100 mg/L, pKa 8.01. They would be best cleaned by Liquinox. Also, Citranox would also work.

Trace Analysis for Alconox, Powdered Precision Cleaner

Question:
Is there a trace of bromine in Alconox?

Answer:
There is a typical trace content of 35 ppm bromine. Most if not all of that bromine is in the form of bromide.

Downloadable Trace Analysis Certificates are available from www.alconox.com for all Alconox brand products.

Cleaning Narrow Neck Flasks

Question:
What is the proper way to clean narrow neck flasks?

Answer:
Narrow neck flasks are best cleaned in labware washers with special attachments that have a spray nozzle that goes up inside the flask. It is very hard to successfully clean narrow neck flasks in a simple home dishwasher or a lab washer that does not have special narrow neck flask racks. The only way to do this is to presoak the narrow neck flasks completely submerged with all the air let out in a 1% Alconox or Liquinox solution prior to "washing" in the machine. Even this can fail if the other glassware cleaned at the same time has a large amount of residue on it which can redeposit on the narrow neck flasks and not be prevented from staying there by the anti-redeposition agents because there can be inadequate amounts of wash solution getting in to the narrow neck flasks without the special wash spindles.

Residue Acceptance Criteria

Question:
Do you have to set residue acceptance criteria for cleaners?

Answer:
Yes. For pharmaceutical and medical device manufacturing it is required that there be set residue acceptance levels for potential residues such as the active drug, excipients, degradation products, cleaning agents, bioburden and endotoxins. These levels are determined based on potential pharmacological, safety, toxicity, stability, and contamination effects on the next product using that surface or equipment. Limits are typically set for visual, chemical, and microbiological residues.

For more information on residue acceptance criteria, visit http://www.alconox.com/static/section_top/gen_cleanval.asp.