Drop Volume Tensiometer – DVT50

Analysis of emulsions under dynamic conditions

The effect of a surfactant as an emulsifier is based on the fact that it reduces the interfacial tensionbetween phases which do not easily mix. As surfactants need a certain time to do this, the effect of an emulsifier depends on the mixing dynamics. With our Drop Volume Tensiometer – DVT50, you can measure the speed with which emulsifiers produce their effect and reduce the interfacial tension. The DVT50 spectrum ranges from very fast to very slow processes. This enables the dynamic mixing behavior as well as the stability of an emulsion at close to the quiescent state to be determined in a single measurement. The results of the measurement help to precisely optimize and dose surfactants for emulsions.

Automatic, accurate analysis

The instrument analyses the samples fully automatically and without interruption by self-refilling of the dosing syringe. The special design of our dosing capillary ensures high accuracy, and dispenses with the calculation of corrections, which are otherwise necessary with drop volume measurements.

Precision also distinguishes the DVT50 tempering unit, which brings the two liquid phases to the required temperature uniformly and reliably. This avoids measurement variations due to thermal imbalance. The wide temperature range of -10 to 90 °C enables process conditions to be simulated in order to optimize the addition of surfactants for the actual conditions.

Variable measuring arrangement for different types of emulsion

With the DVT50, we have provided a flexible arrangement of measuring cell and dosing capillary to facilitate the simulation of the proportions in oil-in-water emulsions and water-in-oil emulsions. The results therefore enable the particular emulsion type to be optimized for the actual process. To achieve fast sample changeover and correspondingly high sample throughput, we have made sure that the instrument is easy to handle when filling and cleaning.

Transparency in measurement and data management

With integral and flexibly adaptable measuring templates, our LabDesk tensiometer software reduces your preparation time to a minimum. LabDesk supports simple results management with automatic overview diagrams, comprehensive measuring reports and transparent data organization. In addition, data which originate from different types of tensiometer can be managed in a common database. Our integral, comprehensive and expandable substance database makes LabDesk a data pool of all important substances.

Tasks and applications

• Emulsifiers in the pharmaceutical and cosmetics industry
• Food production
• Tertiary oil recovery (Enhanced Oil Recovery, EOR)
• Cleaning
• Surfactant development
• Investigation of fuel-water mixtures

Measuring methods and options

• Measurement of dynamic interfacial tension between two liquids with
  free assignment of drop phase and bulk phase
• Measurement of surface tension of a liquid
• Temperature control from -10 to 90 °C