Sulfur content in liquefied gas

For catalytic liquefied gas, we use test tubes for detection; the hydrogen sulfide level is around 7,000 ppm.

The sulfur content in catalytic liquefied gas can be measured; there is hydrogen sulfide and total sulfur.

If no detection is possible, it is either due to a malfunction in the instrument or insufficient precision of the instrument. However, under normal circumstances, the desulfurization process for liquefied gas does not achieve such a high removal rate of total sulfur. There is still some inactive sulfur that cannot be removed.

Anyway, at least here we have hydrogen sulfide as one of the indicators in routine analyses!

As the teachers above mentioned, routine testing of total sulfur and hydrogen sulfide in liquefied gas is necessary

Don’t understand what the original poster means? Is it impossible to detect, or can’t it be detected? The common indicators for hydrogen sulfide control are hydrogen sulfide and total sulfur! Here are the relevant analysis methods: Liquefied gas analysis. Principle: The sample gas is introduced into the analysis column through a sampler, where separation occurs due to the different adsorption capacities of the fillers in the column for various components of the sample. The TCD detector is used for detection, and the signals are amplified and processed to obtain the final results. The total analysis time is approximately 1 hour. Steps: 1. Prepare the instrument; it takes about 30 minutes for the temperature to reach a stable level. 2. Inject the sample – ensure the gas sample is well mixed and undergoes gas exchange for 3–5 seconds. 3. Wait for the peaks to appear, which takes about 20 minutes. 4. After the peaks have appeared, retrieve the corresponding data for further processing. 5. Finally, process the results and record them. Precautions for sample collection: The sample must be free of water and H2S. Coulombic sulfur analysis is used to determine the total sulfur content in gases such as catalyzed liquefied gas, dry gas, propylene, and propane. Principle ； The sample burns with oxygen at high temperature to produce sulfur dioxide, which is then carried by nitrogen into the titration cell where it reacts; the amount of the substance is determined based on the volume of titrant consumed. The total duration of the experiment is 2 hours. 1 Sampling ； Use a tin foil bag for sampling to ensure it is airtight and that the sample is representative. 2 Power on and heat up ； Constant temperature. Turn on the power of the instrument and set the temperature; once the temperature is stable, introduce gas and replace the electrolyte. 3 Marking samples for production ； Select appropriate reference samples to calculate the conversion rate, take the average value, process the sample, and finally use the reference samples for reverse calibration. 4 Shut down for cooling 5 Precautions ； 1 The sulfur content must not exceed 1000PPM. 2 The electrolyte needs to be replaced after two hours of use. Analysis of thiol sulfur in stable gasoline and gasoline after hydrogenation; analysis time: 40 minutes; 1 sample taken ； Use a clean bottle for sampling to ensure the sample is representative. 2 Take 100 milliliters of the basic solvent, and take an appropriate amount of sample for analysis depending on the sample concentration. 3 Wait for the potential to stabilize. 4 Replace the fixed titrant and select an appropriate titration rate for the titration. 5 The instrument automatically determines the endpoint. 6 Record the final result

The sulfur in liquefied gas is mainly H2S; this hydrogen sulfide is definitely present, though in varying amounts. During fluctuations in device production, H2S levels range from 4000 to 5000 ppm. Suggestion for the poster: When you say it cannot be detected, do you mean for a single sample or multiple samples? If it is an occasional occurrence, additional sampling for analysis is recommended. If this happens with multiple consecutive samples, and there are no issues with the instrument or the testing method, but you still feel concerned, it is advisable to have the analysis done by an external laboratory.