- 1It introduces reference: kauri acid, sterol beer, Mulberroside B, Monsanto ketone C, N- trans-ferulic acid tyramine, ski
- 2New exclusive worldwide: A Fritillary base level off Tony base A Fritillary Fritillary alkali alkali acetate propionate,
- 3Determination of electrophoretic paint resistant to salt spray
- 4Latest Release: 7- epi-10-deacetyl paclitaxel HPLC: 99.48%
- 5Our newly developed celandine red base technology program
- 6Test methods and reagents Instrument nitrite need to use, what needs attention
GC common organic cleaning and maintenance
According to the following gas chromatograph in our company use, respectively, gas chromatograph internal cleaning, electrical parts, circuit boards, inlets, TCD detector, FID detector maintenance and cleanliness make a brief introduction.
1 inside the instrument purge and clean
After GC stop, open the sides and rear of the instrument panel, purged with instrument air or nitrogen dust inside the instrument, to a greater or dust is not easy to sweep with a soft brush with the local process. After purging is complete, the presence of organic pollution inside the instrument places with water or solvent scrubbing, water-soluble organic substances can be wiped with water, non-water-soluble or water may react chemically with organic matter may choose not with reacting the organic solvent for cleaning, such as toluene, acetone, carbon tetrachloride and the like.
2 board maintenance and cleaning
GC ready before overhaul, cutting off power to the instrument, instrument air or nitrogen with a first circuit board and the circuit board slot purge carried out with a soft brush with slots for circuit boards and more dust portion purge carefully clean. During operation try to wear gloves. After the purge is completed, the board should be carefully observed usage, see the printed circuit board or electronic components for visible corrosion phenomena. Electronic components on the circuit board contaminated with organics
And printed circuit with cotton dipped in alcohol wipe carefully. In the gas chromatograph in my company''s use an example: each year overhaul will find instrument
A circuit board contaminated with varying degrees of organic vapors. Wherein, MTD contamination is particularly serious, the MTD contaminated surface of the board into a red-brown color, and adsorbed onto a printed circuit board connector and the slot portion of the dust and vapor adsorption mutual MTD between electronic components and easily causing a short circuit between the electronic components, instruments may even burn.
3 Inlet cleaning
GC for quantitative analysis of organic compounds and a polymer compound of the general use of split injection, capillary column; Inlet split control systems are generally split EPC control and manual control split two cases. In the maintenance of the GC inlet glass liner, gold seal, inlet
The flow line, EPC and other components were cleaning is necessary.
Glass liner and gold seal cleaning: Carefully remove the instrument from the glass liner with tweezers or other gadgets Carefully remove glass wool and other impurities within the liner, pipetting process not to scratch the surface of the liner. If conditions permit, it can be preliminary cleaned the glass liner in an organic solvent with ultrasonic cleaning, drying after use. Shunt plate is the most ideal method of cleaning in a solvent, sonication, drying after use. If the conditions are not up to it, you can choose a suitable organic solvent cleaning: after removing from the inlet gold seal, the first use of an inert solvent such as toluene wash, alcohol solvents such as methanol and then washed, dried and then use.
Flow line cleaning: When gas chromatograph for analysis of the organic substance and a polymer compound, the lower the freezing point of many organic compounds, the sample from the gasification chamber via the vent flow line process, part of the organic matter in the flow line solidified. GC after a long period of use, the inner diameter of the shunt line will gradually become smaller, or even completely blocked. In the repair process, regardless of whether the judge prior shunting line clogging phenomenon, we need to split pipeline cleaning. Diversion pipeline cleaning generally opt for acetone, toluene and other organic solvents, severe blockage of flow line sometimes simple cleaning methods are difficult to clean, need to take some other auxiliary mechanical method to complete. For EPC control shunt gas chromatograph, due to prolonged use, it is possible to make some small injections into the foam pad and EPC gas line interface, is subject to partial clogging of the EPC or cause the inlet pressure. So every time the repair process as much as possible on the part of the instrument EPC check with toluene, acetone and other organic solvents for cleaning and drying.
Since the injection and other reasons, the inlet may form at any time of the external part of the condensation of organic matter, you can use cotton dipped in acetone, toluene, and other organic matter on the inlet preliminary wiping, and then to the removal of organics indelible mechanically , careful attention must be removed in the process of solidification of organic matter, do not damage the components of the instrument.
4 TCD and FID detector cleaning
HP''s TCD detector can be used to solve the thermal cleaning method, as follows: Turn off the detector, the detector is removed from the column header, the column inside the detector joint, blocking dead blocked the reference gas flow set to 20 ~ 30ml / min, set the detector temperature was 400 ℃, thermal cleaning 4 to 8 hours, it can be used after cooling.
FID detector cleaning: FID detector in use, good stability, the requirements are relatively low, the use of common, but in the long course, easy to detect nozzle and collector coke and other problems, or organic matter or collector nozzle at the deposition conditions.
Gas chromatography is commonly used in general laboratory analysis equipment, gas chromatograph maintenance and upkeep is a problem often encountered laboratories. However, due to different circumstances, the difference pollutants and working environment, laboratories processing method used may vary. Proper instrument maintenance and repair, increase equipment life, reduce equipment failure rate to ensure the smooth conduct analytical work. Especially factory laboratories, instrument maintenance and regular maintenance is an essential laboratory work, and even affect the production and economic benefits.
Previous: No! ! Next:Monocrotaline introduction and use What precautions