Types of Pumps Used in Chromatography
a. Reciprocal Piston Pumps, (Analytical, Semi Prep and Prep Pumps for use in Isocratic and gradient mode in Flash, MPLC, HPLC and UHPLC Chromatography.)
b. Syringe Pumps, (For precise dosing in automated applications, diagnostics etc)
c. Special Pumps.(Parallel LC Pumps, Valveless Metering Pumps)
Piston Pumps are used to create pressure in the eluent. The eluent is pumped through a packed Column or cartridge. The column is packed with chromatography beads. The smaller the beads the better the separation resolution. Thus we differentiate between 1. Flash or MPLC Pumps, 2. High-Pressure Pumps (HPLC) and Ultra High-Pressure Pumps UHPLC)
In chromatography, we require laminar flow. Thus we do not want any form of pulsation. Pulsation elimination can be achieved by I. using reciprocating piston design with two or three pump heads. II. Designed stroke length III. By complex electronic (software) means.
The basic elements of the pump are a cylindrical pump chamber that holds the piston, a motor that operates a driving cam, a pump seal, and a pair of check valves. As the motor rotates, the piston is moved in and out of the pump chamber. In most pump designs, the pistons are made of sapphire, but also stainless steel and graphite are sometimes used. The check valves serve to control the direction of the flow of the mobile phase through the pump (flow is from bottom to top).
The third dimension is the size of the pump. We differentiate between ∝. Analytical pumps (0.1-10 ml/min Flowrate) ß. Semi-prep Pumps, (1-50 ml/min. Flow rate). γ. Prep-Pumps, (1- 2000 ml/ min flowrate). Δ. Production scale Pumps (multi liter flow rates)
Important components e.g. Check Valve: In their simplest form, the valves comprise a ruby ball and a sapphire seat that is slightly ground (“lapped”) to ensure a leak-free seal when the ball rests on the seat. The valves are open and close in response to pressure and gravity. The pump seal keeps the mobile phase from leaking out around the piston when the pump is under pressure and keeps air from leaking in when the pump is filling.
Wit the accumulator piston pump the two pistons deliver at different rates. For example, let’s say that we want a flow rate of 1 mL/min; the top piston will operate at 1 mL/min and the bottom one at 2 mL/min. There are three check valves, an outlet (top) and an inlet (bottom) plus a middle check valve that acts as in inlet check valve for the top piston, but an outlet check valve for the bottom piston. In the cycle shown in Figure 3, the top piston delivers 1 mL/min to the column, with the outlet check valve opens and the middle check valve closed, just as if it were a single-piston pump. Meanwhile, the bottom piston fills at 2 mL/min with an inlet check valve opens, and the middle check valve closed. On the alternate cycle (not shown), the bottom piston delivers at 2 mL/min; 1 mL/min serves to fill the top piston and the other 1 mL/min flows to the column. Thus, 1 mL/min of the mobile phase always flows to the column. The accumulator-piston pump is also a very popular pump in modern LC and UHPLC systems.
Economic consideration: The higher the pressure the higher the purchasing and maintenance costs. Large UHPLC pumps are available but not used in chromatography. They are only used in Analytical application to safe solvent costs.
Maintenance Consideration: It depends on the user’s perspective. If you maintain the equipment yourself you should go for the high-quality pumps with traditional engineering. LCC Consensus Pumps are very solidly built (Heavier than other pumps ) and run for 20 and more years maintenance-free. With other pumps, you need software specialists and maintenance contracts.
Such Pumps are used also in other applications such as SFC, injection into the geological structure
Syringe Pumps are used for very precise volumes dosing in a wide range of applications such as Diagnostic manufacture or sample injections etc. Most pumps are custom built to specific applications ranging from nano, micro, and ml dosing.
Consensus Syringe Pumps dose with extremely high accuracy and pulsation-free from ml, ul down to nl range.
In simple words, a syringe pump is one or many syringes. The piston is connected with a stepper motor that moveth the plunger without vibration. Thus the liquid to be delivered exudes extremely smoothly.
Syringes can also be exchanged with sterilizable and chemically inert glass syringes or Polymer-based syringes
Consensus Syringe Pumps are for a wide range of challenging applications in research, industry, and development, There are applications in the field of flow chemistry, in-vitro diagnostics, micro-reactions equipment, and microfluidics. They all depend on pulsation-free performance in the creation of fluid streams. This is because small flow rates in the nanoliter range require utmost precision and incredibly smooth operation. When using our syringe pumps, you can rely on highly accurate mechanical components, enabling continuous processes, improved product quality, production flexibility, and cost-effectiveness.
Consensus syringe pumps are used with the following application:
- Dosing of reaction solutions for screening applications and miniaturized syntheses in microfluidics
2. Highly accurate fluid dosing and creation of minimal, precisely defined fluid streams
3. Various lab-on-chip applications, such as DNA amplification (PCR chip)
4. Creation of micro-serial sample flows in high-throughput applications
5. Dosing of reagents with periodical gradients for the creation of compartment sequences with variable concentration of ingredients (creation of parameter spaces, e.g. inactive agent research
6. Infusing calibrant into a mass spectrometer or reaction chamber.
7. Long term drug infusions to animals and general infusion applications.
Consensus Nano Pump
The Consensus NanoPump pumps liquids in a precise, uniform flow without fluctuations. This is made possible by the control of two independent syringe drives.
While one syringe is dispensing liquid, the other syringe is preparing for the next stroke. This way a seamless transition is guaranteed. The flow is therefore pulsation-free. Inlet and outlet valves are positively controlled and the pump is self-priming.
Depending on the pair of syringes installed, the flow rates cover areas from 84 nanoliters per minute to 75 milliliters per minute.
Finite dosages are also part of continuous delivery. This is achieved with three parameters: 1. Flow rate, 2. Volume and 3. Dosing time.
The Consensus NanoPumpi can be controlled and monitored via the RS232 interface as well as with analog and TTL signals.
In the basic version, Windows software used to operate the Pump
For standalone operation, there is a PDA controller with a touchscreen available.
In addition to the function as a pump, each syringe drive can be controlled individually. This enables many applications of liquid handling in research, development, production, and process engineering.
Components that come in contact with the medium is based on glass, PTFE, and Kel-F.
Scope of delivery:
Consensus Nano Pump with valves (but without syringes), Windows software, RS232 cable, power supply (110-230V), mains cable.
Delivery range: 83.3 nl / min to 75 ml / min
Funding mode continuously or
The specifications flow rate in nl / min
Dosing volume in µl dosing time in
Pressure range 0 – 6 bar
Accuracy better than 1%
Reproducibility better than 1%
Nano Pump Mini
The NanoPump-Mini pumps liquids in a precise, uniform flow without fluctuations. This is made possible by the control of two independent syringe drives.
While one syringe is dispensing liquid, the other syringe is preparing for the next stroke, so that there is a seamless transition
is guaranteed. The flow is therefore pulsation-free. Inlet and outlet valves are positively controlled and the pump is self-priming.
Depending on the pair of syringes installed, the flow rates cover areas
from 84 nanoliters per minute to 75 milliliters per minute. Except
Finite dosages are also part of the continuous delivery
possible in which of the three parameters (flow rate, volume and
Dosing time) two. The NanoPump-Mini can
be controlled and monitored via the RS232 interface as well as with analog and TTL signals.
In the basic version, Windows software is used to operate the
Pump included. For standalone operation, there is an option
PDA controller with a touchscreen available.
In addition to the function as a pump, each syringe drive can be controlled individually. This enables many applications of liquid handling in research, development, production, and process engineering
to realize. PTFE, Kel-F, and. Come into contact with the medium
Scope of delivery: NanoPump-Mini with valves (without syringes), Windows software, RS232 cable, power supply (110-230V), mains cable.
Control of RS232 interface
I / O port for analog or
Syringe volume 5 µl – 12.5 ml
Full stroke time 10 – 3600 seconds
24 V / DC supply
Dimensions W × H × D 160 × 120 × 160 mm
Weight about 3 kg
Parallel LC Pumps P10 with Ten Heads
This pump contains ten pump heads and pistons that are consolidated in two blocks of five heads. The pump is designed for parallel Flash and MPLC operations. The Pump heads are made from high-quality SS 1.4571.
Our Parallel LC Pump is used in a number of custom manufactured High Through Put system!
High Through Put System must be engineered to customer requirements. Every client has a different set of circumstances and needs. It is important that all variables are taken into consideration (Operators, Skill level, output, chemical engineering, costs, etc)
Please contact us for preliminary discussions. We have more than 20 years of experience in developing many different parallel technologies. We can satisfy any customer’s requirements and budget.
Consensus Valveless Metering Pump E 200
For dosing liquid chemicals, solvents, suspensions, etheric oils, and oils in food applications
The piston is flattened at the front to about 65% of the diameter. Dosing is accomplished by the synchronous rotation and reciprocation of the ceramic piston in the precisely mated ceramic cylinder liner. One complete piston revolution is required for each suction/discharge cycle. In the suction phase , the pressure side is blocked, the axial movement is sucked in since the piston performs a rotating and axial rotation at the same time. The piston reaches a so-called 0 position in the rear position , that is, the input and output sides are blocked. In the forward movement , the pressure side is released and the suction side is blocked. After this, the piston is in the forward position . The process is then repeated.