Test - lowercase jpg

Kaixin micro test

Test probe P100-M3

Brand AVX TPSE226M035R0125 Low impedance tantalum capacitor AVX 22

Determination of phosphorus, silicon, iron, manganese and lead in gasoline by ICP2060T direct injection method

instrument

Introduction

The remarkable features of Petrochemical oil analysis of Tianrui Instrument ICP2060T inductively coupled plasma emission spectrometer:

1. The semiconductor refrigeration sample introduction device improves the stability and sensitivity of the injection, and the test is more accurate and reliable.

2. Gasoline special torch to ensure long-term stability of the plasma and reduce the background of the substrate.

3. Increase oxygen assisted injection to maintain plasma stability and prevent carbon deposition.

4. Self-developed RF solid-state RF generator automatic matching method, suitable for samples such as organic and high matrix

Take in the sample.

5. The height of the plasma observation is automatically adjusted to accurately locate the best observation position.

6. Very high resolution, can accurately separate P213.618nm, Cu213.598nm and P214.911nm,

Experimental part

1.1 Instruments and reagents

Tianrui Instrument ICP2060T Inductively Coupled Plasma Emission Spectrometer

CONOSTANS-21 mixed standard oil, 300 ppm, 100g

CONOSTAN Co standard solution, 5000ppm, 50g

CONOSTANICP special thinner, one gallon.

Pipette, 0-5ml, Prand, Germany

One ten thousandth electronic balance, BS224S, Sartorius

1.2 Instrument working conditions

High-frequency generator: 27.12MHz, quartz torch with 0.6mm center channel, high-frequency power 1100W, reflected power about 50W, plasma gas flow 15L/min, auxiliary gas flow 1.0L/min, carrier gas flow 0.4L/min , oxygen flow rate 30ml / min, spray chamber temperature -10 ° C, peristaltic pump speed 3ml / min, phosphorus analysis line 213.620nm, silicon analysis line 251.611nm, iron analysis line 538.204nm, manganese analysis line 257.610nm, The analytical line for lead is 220.353 nm and the analytical line for cobalt is 228.616 nm.

1.3 Test methods

After the instrument is automatically ignited and the parameters are set according to the working conditions of the instrument, the diluent directly enters the mist chamber through the atomizer and enters the plasma. After the instrument is stabilized, the blank solution, the standard solution and the diluted sample solution are measured once, and the instrument is based on the working curve. The content of each element in the final sample can be directly derived.

2. Results and discussion

2.1 The choice of the best analysis line

In the ICP system, due to the appearance of many molecular bands in the spectrum, a deep spectral background is generated, which affects the analysis of metal elements. The three most commonly used analytical lines for silicon are selected, and the sensitivity of the line is considered after the test. For the background and interference of the spectrum, the analysis line of phosphorus is selected to be 213.620 nm, the analysis line of silicon is 251.71 nm, the analysis line of iron is 538.204 nm, the analysis line of manganese is 257.610 nm, and the analysis line of lead is 220.353 nm. The detection limit and linear range of the calculation method are shown in Table 1.

The linear relationship of the elements was determined experimentally, and the blank solution of each element was repeatedly measured 10 times, and the standard deviation of the measured value was divided by the slope of the curve as the method detection limit. It can be seen from Table 1 that the fitting coefficient of the element working curve is higher than 0.999, indicating that the linear relationship is good in the linear range of the working curve. Since the operating parameters of the instrument are optimized, the test conditions of the elements are optimized to improve the accuracy of the test results.

Table 1 Determination of linearity and detection limit of elements in gasoline samples by ICP

element

Phosphorus (P)

Silicon (Si)

Iron (Fe)

Manganese (Mn)

Lead (Pb)

Working curve fitting coefficient

0.9998

0.9999

0.9999

0.9999

0.9999

Method detection limit / (mg / L)

0.079

0.014

0.004

0.001

0.066

2.3 Sample analysis According to the test method, the gasoline standard sample is determined 10 times. The calculation results of the repeatability data are shown in Table 2.

Table 2 gasoline sample analysis results

element

Measured value / (mg / L)

RSD/%

Phosphorus (P)

0.949

3.63

Silicon (Si)

0.929

1.99

Iron (Fe)

0.904

0.77

Manganese (Mn)

0.933

1.68

Lead (Pb)

0.941

1.97

2.4 Recovery experiment

The organic standard is added to the gasoline sample and the standard recovery test is carried out according to the test method. The results are shown in Table 3.

element

Scaling amount

Measured value / (mg / L)

Recovery rate/%

Phosphorus (P)

0.93

0.949

102.0

Silicon (Si)

0.93

0.929

99.9

Iron (Fe)

0.93

0.904

97.2

Manganese (Mn)

0.93

0.933

100.3

Lead (Pb)

0.93

0.941

101.2

It can be seen from Table 3 that the recovery of phosphorus, silicon, iron, manganese and lead in gasoline by the method is good, indicating that the method has high accuracy and the test result is stable.

3. Conclusion

The direct determination of the multi-element relative digestion method in gasoline by ICP-AES has higher accuracy and better reproducibility, and the test speed is fast, which greatly improves the work efficiency and saves a lot of manpower and material cost. Compared with the high configuration and cost of imported ICP, Tianrui Instrument ICP2060T has the characteristics of low cost, high speed and high accuracy. It can directly measure phosphorus, silicon, iron, manganese and lead in gasoline samples. Test requirements for customers in the petrochemical industry.