FAQs
 | Frequently asked questions about the MultivaporTM. |
Please select one of the related topics:
FAQs concerning the Multivapor Rotavapor Setup
- Is it possible to combine the Multivapor with any kind of rotary evaporators or is it limited to the Rotavapor?
The prerequisite for a compatibility with a glass condenser is a S 35 spherical joint. The glass interface consists of concave S 35 joint at the top and a convex S 35 joint at the bottom. - Combining the Multivapor with the Rotavapor, is there any limitation in the type of condenser?
No. All BUCHI rotary evaporator condenser assemblies consist of a S 35 spherial joints. - Is it possible to run both the Multivapor and the Rotavapor simultaneously?
The parameters which play an important role for the efficiency of the evaporation process between the heating bath of the Rotavapor and the crystal rack of the Multivapor are different. Therefore, even if the same solvent is used, the conditions are not directly comparable. Moreover, regarding the speed of the evaporation process, the limiting steps is always the capacity of the condenser and not the amount of vapor reaching the condenser assembly. To conclude, a simultaneous use is theoretically feasible - given the same solvent is used - but not really sensible. - Is a combination of the Syncore with the Rotavapor in accordance with the Multivapor feasible?
Yes, but very seldom used. Most people use the Rotavapor as a personal and the Syncore as a group instrument. There different requirements in almost any cases entail a stand-alone setup.
FAQs concerning the material
- What are the limitations of PETP and the advantages of PEEK?
Like all polyesters, PETP hydrolyzes under acidic or basic conditions. However, the rate of the polymer degradation depends on the exposure conditions, primarily time and temperature. Results from long-term investigations show a discoloring of PETP after two weeks using acidic acid 10%, brittle material after one month using ammonia 25%, and a complete dissolution after 8 hours using TFA conc.. - What are the recommendations for the O-rings of the conical adapters regarding the material?
This is primarily a question of money. There is a considerable increase in the costs of the material going from the standard EPDM material, to FKM (Viton) or even plastperfluor (Kalrez). It is for most applications probably more advisable and less costly to exchange the EPDM O-rings regularly instead of using plastperfluor. However, EPDM and FKM show some kind of a complementarity. In other words, FKM is resistant against chlorinated and apolor solvents such as hexane where as EPDM is not; on the other hand EPDM can be used for bases and acetone where FKM shows problems (i.e. primarily swelling).
FAQs concerning competitive products
- What are the key advantages of the Multivapor compared with the TurboVap?
The Multivapor is faster, has about the same initial costs but very low running costs, does not need to be placed in a fume hood and is environmentally friendly (i.e. in accordance with the ISO 14000 regulation). - What are the major differences of the Multivapor to vacuum centrifuges in general?
In order to reduce boiling retardation vacuum centrifuges apply a very strong rotation of the whole sample block (so called rotors) which generates a centrifugal force antiparallel to the direction of the vapor stream. This, however, requires a delicate compensation of the rotating mass which is tedious to adjust or costly when performed automatically. The crystal rack of the Multivapor does not rotate but shake which does not require any mass compensation or regular distribution of the samples. It is even possible to occupy only the front positions while leaving the rest empty (by using the blind adapters).
The samples are placed into a vacuum chamber which is sealed with a lid. In the event of boiling retardation or foaming contamination of adjacent samples is inevitable. This is prevented for the Multivapor by its individual sealing system.
There is a number of rotating elements exposed to the vapor of the samples reducing the lifetime of a vacuum centrifuge. The Multivapor on the other hand is based on a separate sealing for each sample onto the moving element. - What are the limitations associated with the Mulitvapor with regard to the Syncore?
The Syncore is based on a modular concept which allows a number of applications beyond evaporation, such as concentration to pre-defined residual volumes, reactions, filtrations, liquid-liquid extractions, low-temperature applications and so on. This diversity in terms of applications and sample volumes and numbers requires a multi-purpose platform and highly resistant materials, both of which entail a high price relative to the Multivapor.
The Multivapor on the other hand is designed for parallel evaporation of up to 12 samples in a relatively narrow volume range (0.5 – 30 ml). The request for highly inert materials is therefore less distinct.