There are three types of potassium chloride products: I am a special industrial use of potassium chloride, which is suitable for electrolysis of potassium hydroxide, potassium chlorate, and other industrial use of potassium chloride Π, suitable for a variety of potassium fertilizer production and chemical industry. Class III agriculture uses potassium chloride, which is suitable for the application of compound fertilizer or directly as fertilizer.

　　本文所述的氯化鉀適用于復(fù)合肥或直接用作肥料。它以白色或紅色晶體的形式存在，其主要成分為氧化鉀。氯化鉀產(chǎn)品氧化鉀含量檢測(cè)時(shí)，應(yīng)注意以下幾個(gè)方面:

　　The potassium chloride described in this paper is suitable for compound fertilizer or directly used as fertilizer. It exists in the form of white or red crystal, and its main component is potassium oxide. In the detection of potassium oxide content of potassium chloride products, attention should be paid to the following aspects:

　　溫度控制是配制溶液的首要條件

　　Temperature control is the primary condition of solution preparation

　　根據(jù)GB/T 6678-2003《化工產(chǎn)品通用抽樣規(guī)則》6.6的規(guī)定，在試驗(yàn)中應(yīng)確定樣品的抽樣單位數(shù)量。采樣器從袋口的一角取樣品袋深的3/4處，將采集到的樣品均勻混合，用四分法將其還原為待測(cè)樣品量。由于氯化鉀肥料具有很強(qiáng)的吸水性，在制備樣品時(shí)應(yīng)盡快進(jìn)行。樣品制備后，稱量5g樣品，取0.001g精度，加入150ml水。然后，樣品在不斷攪拌下加熱，略煮5分鐘。冷卻20℃后，將樣品轉(zhuǎn)移到500ml的容量瓶中。這是一個(gè)關(guān)鍵的環(huán)節(jié)。為了方便一些巡視員，他們并沒(méi)有在水溫達(dá)到20℃時(shí)設(shè)置音量，但是當(dāng)水溫達(dá)到20℃時(shí)，結(jié)果卻很高。當(dāng)水溫低于20℃時(shí)，結(jié)果很低。兩個(gè)恒定體積導(dǎo)致兩個(gè)誤差。因此，準(zhǔn)確的測(cè)試溫度是測(cè)試結(jié)果準(zhǔn)確性的關(guān)鍵。將水溫高于20℃時(shí)的試驗(yàn)結(jié)果與水溫為20℃時(shí)的試驗(yàn)結(jié)果進(jìn)行對(duì)比，如表1所示。

　　According to 6.6 of general sampling rules for chemical products (GB / T 6678-2003), the number of sampling units shall be determined in the test. The sampler takes samples from one corner of the bag mouth to 3 / 4 of the bag depth, evenly mixes the collected samples, and reduces them to the sample quantity to be measured by quartering method. Because potassium chloride fertilizer has strong water absorption, it should be carried out as soon as possible when preparing samples. After sample preparation, weigh 5g sample, take 0.001g precision, add 150ml water. Then, the sample is heated under constant stirring and boiled for 5 minutes. After cooling to 20 ℃, transfer the sample to a 500 ml volumetric flask. This is a key link. For the convenience of some inspectors, they did not set the volume when the water temperature reached 20 ℃, but when the water temperature reached 20 ℃, the result was very high. When the water temperature is below 20 ℃, the result is very low. Two constant volumes result in two errors. Therefore, accurate test temperature is the key to the accuracy of test results. Compare the test results when the water temperature is higher than 20 ℃ with the test results when the water temperature is 20 ℃, as shown in Table 1.

　　洗滌劑和蒸餾水對(duì)試驗(yàn)結(jié)果的影響

　　Influence of detergent and distilled water on test results

　　氧化鉀含量的測(cè)定方法與iso2051:1976《氯化鉀的測(cè)定-工業(yè)用鉀含量-四苯基硼酸鉀的重量法》相同。在弱堿性介質(zhì)中，四苯基硼鈉[NaB(C6H5)4]堿性溶液和洗滌液直接影響試驗(yàn)結(jié)果。由于制備的四苯基硼鈉很不穩(wěn)定，容易產(chǎn)生渾濁。如使用前發(fā)現(xiàn)渾濁，應(yīng)先用中速濾紙過(guò)濾，否則測(cè)試結(jié)果過(guò)高。洗滌液和蒸餾水的效果也不同。有些檢驗(yàn)員認(rèn)為配制洗滌液，用蒸餾水代替洗滌液比較麻煩，檢測(cè)結(jié)果會(huì)比較低。蒸餾水的原始結(jié)果與洗滌劑的正確結(jié)果的比較如表1所示。

　　The determination method of potassium oxide content is the same as iso2051:1976 determination of potassium chloride content of potassium for industrial use weight method of potassium tetraphenylborate. In the weak alkaline medium, the alkaline solution and washing solution of sodium tetraphenylborate (NAB (C6H5) 4) directly affect the test results. Because the preparation of sodium tetraphenylboron is very unstable, it is easy to produce turbidity. If turbidity is found before use, filter with medium speed filter paper first, otherwise the test result is too high. Washing liquid and distilled water have different effects. Some inspectors think that it is troublesome to replace the detergent with distilled water when preparing the detergent, and the test results will be relatively low. The comparison between the original results of distilled water and the correct results of detergent is shown in Table 1.

　　洗滌步驟是關(guān)鍵

　　Washing step is the key

　　試驗(yàn)中，試驗(yàn)液過(guò)濾后的洗滌步驟存在洗滌終點(diǎn)不清的問(wèn)題。根據(jù)GB 6549-1996氯化鉀的規(guī)定，先提取上清液過(guò)濾，再用洗滌液(即氯化鉀溶液)將沉淀轉(zhuǎn)移到過(guò)濾器中。，室溫飽和四苯基硼鉀溶液)。上述洗滌液繼續(xù)洗滌沉淀約12次，每次洗滌約5ml洗滌液。如果檢查人員沒(méi)有清洗足夠的次數(shù)，在干燥的坩堝上可以清楚地看到粉紅色物質(zhì)，這是未清洗的氫氧化鈉和酚酞產(chǎn)生的物質(zhì)的顏色，終會(huì)導(dǎo)致高鉀含量。因此，洗滌次數(shù)不應(yīng)少于12次。將洗滌次數(shù)少于12次的原始結(jié)果與不少于12次的正確結(jié)果進(jìn)行比較，如表1所示。

　　In the test, there is a problem that the end-point of washing is not clear after the test solution is filtered. According to the provisions of potassium chloride in GB 6549-1996, the supernatant is extracted and filtered first, and then the precipitate is transferred to the filter with the washing solution (i.e. potassium chloride solution). , room temperature saturated potassium tetraphenylboron solution). The above washing solution is washed and precipitated for about 12 times, and each time about 5ml of washing solution is washed. If the inspector does not clean enough times, the pink material can be clearly seen on the dry crucible, which is the color of the material produced by the uncleaned sodium hydroxide and phenolphthalein, which will eventually lead to high potassium content. Therefore, the washing time should not be less than 12 times. Compare the original result of less than 12 times of washing with the correct result of no less than 12 times, as shown in Table 1.

　　結(jié)論

　　conclusion

　　綜上所述，在對(duì)以氧化鉀為主的氯化鉀產(chǎn)品的檢測(cè)中，應(yīng)充分注意幾個(gè)關(guān)鍵環(huán)節(jié)，避免和克服各種可能引起誤差的因素，以保證檢測(cè)結(jié)果的準(zhǔn)確性。

　　In conclusion, in the detection of potassium chloride products mainly composed of potassium oxide, several key links should be paid full attention to to avoid and overcome various factors that may cause errors, so as to ensure the accuracy of the detection results.