Continuous Determination Of Inorganic And Organic Carbon In Soil Samples By Non-aqueous Titration

Carbon is the main constituent elements for organisms, also, the main source ofenergy. Due to the development of the industry in recent years, the use of carbonenergy transition, resulting in increased atmospheric carbon dioxide concentration.And the irrational use of soil and carbon element also changed the content of soilcarbon. Soil carbon to carbon cycling also plays an important role. So the research onthe carbon content of the soil is very important.Soil carbon is called the soil carbon content, and was divided into inorganic andorganic carbon. At present, the analysis on soil carbon is mainly the analysis ofinorganic carbon, organic carbon and total carbon single. The analysis of inorganiccarbon is mainly weight method, acid-base titration, non-aqueous titration. Thenon-aqueous titration method because the method is simple, good stability, lowdetection limit, method of little environmental pollution is widely used in geologicalprospecting. Method for analysis of organic carbon includes weight method,colorimetric method, potassium dichromate sulfuric acid oil bath smelting method,microwave digestion method. The method of potassium dichromate sulfuric acid oilbath smelting of simple, easy operation, stability is relatively good, high accuracy hasbeen widely used in geological survey. The analysis method of total carbon weightmethod, burning, non-aqueous titration, infrared carbon sulfur analyzer determinationmethod. The principle of the non water titration burning, simple, convenient, cheapreagents, good stability, and less pollution is widely used in geological exploration.Based on the previous analysis of the methods for determination of carbon,carries on the transformation to the determination of carbon dioxide device nonaqueous titration, design of disposable continuous measurement of inorganic carbon,organic carbon. The sample adding dilute sulfuric acid in boiling condition, carbonatereaction releases carbon dioxide, which is the three ethylene amines two ethanolsolution absorption, titration with potassium hydroxide in ethanol solution, thecalculation of inorganic carbon content; potassium dichromate sulfuric acid solution to add boiling organic carbon is oxidized and the release of carbon dioxide in thesample, which is three of ethylene amines two ethanol solution absorption, titrationwith potassium hydroxide in ethanol solution, calculate the organic carbon content;inorganic carbon and organic carbon and the total carbon. In this method adetermination of inorganic and organic carbon, simplify the experimental procedure,reduce the cost, save the test time, remove organic carbon and total carbon content ofcontrast problem. Application of this method through experiments on benchmarkcalcium carbonate, determine the best experimental conditions: smelting temperature,gas flow rate, etc.. Under the optimum reaction conditions, the feasibility experimentof national soil standard reference material, this experiment determined the methodmeets the requirements of geological test. To continue the experiment on low contentsamples to determine the sample weight, increase in lower concentration of KOHethanol solution and, can improve the detection limit and the accuracy. Experiment ofthe high content of samples determined in potassium dichromate, insufficient amountadded to experiment, does not affect the experimental results. According to thedetermination method, using4kinds of state standard of soil samples,12parallelexperiments, the data were analyzed for accuracy and precision, can reach the nationalstandard, with satisfactory results.The improved method to solve the organic carbon and total carbon separatedcontrast, when measuring method is simple, good stability, high accuracy, littleinterference, improve the detection limit of the method, the feasibility of strong. Thismethod uses line of strong, fully meet the National Geological Survey anddetermination of carbon in.