Agitation and cleaner selection

Question:
Does agitation in a given cleaning method impact the cleaner or detergent used?

Answer:
Yes, agitation used in a particular method does impact the cleaner or detergent used! In fact, agitation is a factor in detergent choice. High emulsifying, high foaming cleaners are more effective for cleaning processes with low levels of agitation and longer cleaning time. These include the manual, soak and ultrasonic processes. Likewise, low foaming, high dispersing cleaners are suitable for high-agitation cleaning with short contact time as found in spray washing, parts washing and when using spray CIP systems, etc.

Alconox, Inc has both high emulsifying cleaners as well as low foaming cleaners. Visit Alconox.com to find an appropriate cleaner for your application.

Cleaning Insecticide Components

Question:
What Alconox brand cleaner is best to clean carbamates and synthetic pyrethroid off of stainless steel?

Answer:
Carbamates and synthetic pyrethroids are commonly used in insecticides and can be cleaned off stainless steel using an alkaline cleaner that targets the ester groups. The alkaline cleaner used will be determined by the method of cleaning. Our recommendation for manual cleaning is Liquinox and for machine cleaning is Solujet.

For downloadable Technical bulletins, MSDS and trace analysis on Liquinox or Solujet, visit Alconox.com.

Alconox and unstressed polycarbonate

Question:
Is Alconox Powdered Precision Cleaner compatible with unstressed polycarbonate?

Answer:
Alconox is compatible with unstressed polycarbonate. If there is stress in the polycarbonate, then any low surface tension solution such as Alconox will act as a stress cracking agent, especially with the addition of a little heat. Warm solutions of Alconox will cause stress cracking on stressed polycarbonate. The same warm solutions of Alconox will not attack unstressed polycarbonate.

Stress cracking is a surface attack causing fogging, crazing, or slight surface cracks. This stress cracking does not particularly affect the mechanical properties of the polycarbonate, but it does make the polycarbonate less transparent and it does make the surface of the polycarbonate rougher.

For downloadable Technical Bulletin, MSDS and trace analysis on Alconox, visit Alconox.com

Temperature and Alcojet

Question:
What is the lowest recommended washing temperature for Alcojet to guarantee full dissolving?

Answer:
There is no minimum temperature to assure dissolving of Alcojet as it is completely water soluble and will dissolve with agitation over the course of any standard labware washer cycle. Note that while the detergent may dissolve, it will not perform optimally at temperatures below 45 deg C. There is an anti-foaming nonionic surfactant that is heat activated at this temperature and above. Failure to clean at above this temperature will result in foam from the surfactant and potentially foam from any foam forming residues. Foam is harder to rinse and can potentially result in residues. Foam can interfere with the mechanical action of spray which can result in less efficient cleaning. Most labware washers are designed to be used with hot water. Alcojet is designed to be used with hot water. As a general rule, every 10 deg C you go up in temperature, you double the cleaning speed. Cleaning mechanisms still work at lower temperatures, they just work more slowly and longer cleaning cycles may be needed. Additionally there is the non-linear foam issue at about 45 dec C. You could get adequate cleaning at lower temperatures below 45 deg C if you incorporate additional rinsing and take special care loading glassware to avoid any solution/foam holding "cups" such as the upturned bottom of a graduated cylinder where foam can congregate. If you are going to clean at temperatures below 45 deg C, the residues need to be cleanable within standard cleaning cycle times, or additional cleaning cycles may be required.

To download technical information on Alcojet, please visit Alconox.com.

Citranox vs Citrajet

Question:
What is the difference between Citranox and Citrajet?

Answer:
Both Citranox and Citrajet are acid cleaners excellent at removing inorganics, metallic complexes, trace metals and oxides, scale, salts, soil, grit and oils off glass, metal, stainless steel, porcelain, ceramic, plastic rubber and fiberglass. Can be used on soft metals such as copper bronze aluminum zinc magnesium if rinsed promptly.

The acid cleaning part of both formulations is the same but the major differences are the types of surfactants used. Citranox contains two high foaming, high emulsifying surfactants that work best in the environments of immersion and manual cleaning where more time is available to form micelles. Whereas, there are three surfactants in Citrajet that are considered "low" foaming with wetting and dispersing properties that work better in the dynamic cleaning environment of high agitation spray cleaning, where emulsifying is a less dominant cleaning mechanism. Also, Citrajet contains an antifoam agent.

To download technical information on Citranox or Citrajet, please visit Alconox.com.

Rexolite

Question:
Can Alconox Powdered Precision Cleaner be used to clean Rexolite®?

Answer:
Rexolite® is a unique cross linked polystyrene microwave plastic made by C-Lec Plastics, Inc. Two different forms are available; Rexolite® 1422 and Rexolite® 2200. (2200 is a fiberglass reinforced version of 1422). From what we understand based on the Rexolite Chemical Resistance information listed on the Rexolite website, Rexolite is not affected by alkalies, alcohols, aliphatic hydrocarbons and mineral acids. Aromatic & chlorinated hydrocarbons cause swelling and should be avoided.

Since Alconox Powdered Precision Cleaner is a mild alkali and contains no aromatic or chlorinated hydrocarbon, no problems are likely to occur. Alconox, Inc does recommend testing Alconox on a piece of Rexolite prior to use.

Alconox technical bulletin and msds are downloadable off our website at Alconox.com.

Rinsing sulfonate & trace sodium sulfate

Question:
Can the sulfur content in Liquinox be easily removed during a rinse cycle with room temperature water and with 130°F water?

Answer:
The sulfur content in Liquinox is an organic sulfonate surfactant and trace sodium sulfate impurity. The surfactant is highly water soluble and has a rinse aid characteristic that renders it readily rinseable. The trace sodium sulfate is also highly water soluble and easily rinsed, plus there is not much of it there to start with. So, yes, the sulfur content is easily removed.

For downloadable technical bulletins, MSDS and trace analysis on Liquinox, visit Alconox.com.

Machine Washers

Question:
What method of cleaning is best for disassembled equipment and bench-scale production equipment for clean-out-of-place (COP) procedures?

Answer:
Machine cleaning is performed on clean manufacturing tools, disassembled equipment and bench-scale production equipment in clean-out-of-place (COP) procedures. A machine that is designed to meet Good Manufacturing Practice (GMP) requirements can provide rapid, reliable, validated cleaning while using minimum amounts of water, resources and space. Historically, "lab style" washers have been modified to conform to GMP requirements. More recently, washers have become available that meet GMP requirements with design features including:

1. A chamber that allows for minimal water retention and provides good drainage from cycle to cycle with a minimum of solution carried over in any inlet or outlet piping. Corners that carry a minimum of a 1" radius and all surfaces are sloped to the drain. Internal chamber structures have rounded edges with no threads or fluid entrapment areas.
2. No mechanical attachment required for the accessory racks with regard to the mating of inventory systems to the hydraulic circuit.
3. Spray headers are positioned on the top and bottom of the racks to provide the most efficient cleaning.
4. A documentation package to complete the validation and qualify the cleaning system.

A well designed machine washer requires GMP compliant procedures for best use. In this regard, a complete inventory of size, weight, and specific cleaning requirements for each part and equipment to be cleaned needs to be taken. Additionally, which parts and equipment need to be cleaned together have to be noted. Cumulatively, with this information, appropriate loading and unloading patterns can be established. The goal of a good loading pattern is to allow good spray and cascading solution contact and good drainage of the parts and equipment. Any opportunity for pockets of solution to fail to drain from parts or equipment in between wash or rinse cycles need to be eliminated. By designing multi-level loading patterns, efficient use of water, detergent and utilities can be achieved. Since loads for GMP cleaning can range from glass to plastic to stainless parts, the design of a loading surface should allow for varying weights. If horizontal drop-down doors are used in the washer, they can serve as both the integrated loading platform when open and can allow for better seals than vertical doors when closed. Vertical doors typically require the use of separate loading carts. For these reasons, horizontal doors are often preferred.

Once good loading patterns have been established with proper racking, the pre-rinsing, washing, rinsing and drying cycles must be established. This involves selecting the correct cleaning agents, temperatures and time for each cycle. By knowing the substrates and residues that need to be cleaned, the correct cleaning agent can typically be determined. Typically a high alkaline cleaner followed by an acid rinse is used. Other important washer design features that should be taken into consideration at this point include that the delivery systems allows for precise application of additives and that a set-up of drying systems are in place that provide complete coverage of every part of a load. Once the appropriate parameters have been established, cleaning programs using the machine’s Programmable Logic Controller (PLC) are set.

The advantages of using machine washers are faster cleaning of parts and equipment using less human labor, less space, less water and less cleaning agent than comparable manual cleaning. A disadvantage of machine washers is that they often require very special racks and correct loading procedures to assure reliable cleaning results on parts or equipment with complex geometry.

To find the right Alconox aqueous critical cleaner for your machine washer visit Alconox.com.