The 6 Channel 4700 Precision Diluter represents the next generation in accurate canister standards preparation. Utilizing a combination of precise gas flow control, exact pressure measurements, and an ultra-inert flow path, the 4700 is capable of performing multistage dilutions for achieving standards ranging from part-per-billion to low part-per-trillion. The 4700 works with canisters and Bottle-Vacs™ to create dilutions up to 100x, and then allows a second dilution of up to another 100x to yield a total 2 step dilution of up to 10,000x.
With the 4700, small 100L cylinders at 1PPM will allow over 15,000 6L canisters to be filled to atmospheric pressure with a 1PPB mixture by first making a 20PPB working standard that can be further diluted into each canister to be tested. This results in just pennies worth of standard being consumed when performing inertness testing of canisters every 1-2 years. By contrast, typical dynamic diluters that must balance flows and pressures can typically only fill 50–100 6L canisters per high concentration cylinder, making field canister inertness testing prohibitively expensive.
4700 Prepares the 20PPB standard from 1PPM cylinders, then re-dilutes the 20PPB standard further down to 0.4 PPB. The 7200 can take different volumes from each canister to dramatically increase the dynamic range while performing GCMS calibrations and method validations
An optional digital scale can be used to validate dilution ratios gravimetrically, thus eliminating any need for expensive annual sensor calibrations.
The 4700 comes standard with six channels. This allows for dedicated ISTDs, CalSTDs, and sample dilution channels.
The 4700 Precision Diluter can easily perform 1–100x dilutions (100 PPB to 1 PPB), or dilutions up to 10,000x by using CH6…
The 4700 conserves cylinder standards relative to dynamic blending.
The 4700 can create 1 PPB challenge standards for 6L canister inertness validation tests. (One 102L cylinder ﬁlls 1800 6L canisters).
High concentration samples such as soil gas can be eﬀortlessly diluted with the 4700.
The current EPA NATTS Technical Assistance Document, and soon the updates to EPA Method TO15 require recovery testing of VOCs being reported through each sample train and canister on a periodic basis. Each sample train and canister must show >80% recovery of target compounds. Entech has an easy solution that provides a full 24-hour continuous challenge stream at low to sub-PPB levels through up to 5 samplers and canisters at a time. Read More
The 4700 uses precise pressure control, rather than mass flow controllers to meter in the standard. This approach has several advantages. First, very little of the standard mix is used in making a standard. This allows the original cylinder to last longer, keeping cylinder pressures higher where contents are more stable. Secondly, the mixing region used in a dynamic diluter is eliminated, substantially reducing surface area and carryover.