基于硅钼黄法，以高温消解-分光光度法测定稠油采出水中活性硅、胶体硅、吸附硅、溶解性有机硅、颗粒硅等5种硅形态的含量（均以二氧化硅计）。取水样10.00 mL，分别按照以下步骤试验：①水样过聚四氟乙烯（PTFE）滤头，加入盐酸溶液，并用400 g·L^-1四水合酒石酸钾钠溶液1 mL和250 g·L^-1一水合草酸钾溶液1 mL掩蔽Fe³⁺和PO₄^3-的干扰（总铁和总磷质量分别小于3 000，250 μg时适用），在试验组中加入仲钼酸铵用于显色反应（色度补偿组加入氯化铵），以水为参比，在400 nm处测定显色体系吸光度，以试验组和色度补偿组吸光度差值计算目标吸光度，并以此计算活性硅的质量浓度（ρ₁）；②水样过PTFE滤头，加入氢氟酸（将水中胶体硅分解为活性硅），在水热釜中于100℃消解20 min，加入氯化铝，用于消除多余F^-，洗涤后定容，后续检测步骤同①，所得结果（ρ₂）与ρ₁的差值即为胶体硅的质量浓度；③水样不过滤，直接按照②提供的方法进行前处理和检测，所得结果（ρ₃）与ρ₂的差值即为吸附硅的质量浓度；④在水样中加入氢氟酸和过硫酸钠（将水样中溶解性有机硅消解为活性硅），在水热釜中于120℃消解30 min，加入氯化铝，洗涤后定容，后续检测步骤同①，所得结果（ρ₄）与ρ₃的差值即为溶解性有机硅的质量浓度；⑤在水样中加入氢氧化钠（用于消解水样中颗粒硅和胶体硅）和过硫酸钠，在水热釜中于200℃消解120 min，加入硫酸，洗涤后定容，后续检测步骤同①，所得结果（ρ₅）与ρ₄的差值即为颗粒硅的质量浓度。二氧化硅基准物质配制的标准溶液系列经干扰掩蔽、消解、显色处理后检测，所得硅（以二氧化硅计）的质量均在500~5 000 μg内与其对应的吸光度呈线性关系，硅（以二氧化硅计）的检出限为4.0~7.1 mg·L^-1。分别在实验室内和实验室间对硅标准溶液进行精密度和准确度试验，实验室内和实验室间总硅测定值的相对标准偏差（n=5）分别为0.85%~4.5%和2.1%~5.0%，相对误差分别为-7.4%~0.47%和-4.5%~-1.7%，回收率为95.8%~96.8%。方法用于实际样品的分析，活性硅含量占总硅的比例为94%~97%，建议以化学沉淀法去除稠油采出水中的硅杂质。

Based on Si-Mo yellow method, the method for determination of 5 morphologies of silicon (calculated as SiO₂), including active silicon, colloidal silicon, adsorbed silicon, dissolved organic silicon and granular silicon in the produced water of heavy oil was proposed by spectrophotometry after high temperature digestion. The water sample (10.00 mL) was taken and tested by the following steps, respectively. ① Water sample was passed through PTFE filter, and mixed with hydrochloric acid. In the above solution, 400 g·L^-1 sodium potassium tartrate tetrahydrate solution of 1 mL and 250 g·L^-1 potassium oxalate monohydrate solution of 1 mL were added to mask the interference of Fe³⁺ and PO₄^3- (suitable when the mass of total Fe³⁺ and P were less than 3 000, 250 μg, respectively). In the experimental group, ammonium paramolybdate was used for color reaction (ammonium chloride was added in the chroma compensation group). With water as reference, the absorbance of the color system was measured at 400 nm. The target absorbance was calculated by the absorbance difference between the experimental group and the chroma compensation group, and the mass concentration of active silicon (ρ₁) was calculated based on the target absorbance. ② Water sample was passed through PTFE filter, hydrofluoric acid was added to decompose colloidal silicon in water into active silicon, and the above solution was digested in a hydrothermal kettle at 100 ℃ for 20 min. After aluminum chloride was added to eliminate excess F^-, the mixed solution was washed, diluted, and done as follow-up steps with ①. The mass concentration of colloidal silicon was obtained by difference between the result (ρ₂) and ρ₁. ③ Water sample was not filtered, and directly pretreated and detected in accordance with the method provided by ②. The mass concentration of adsorbed silicon was obtained by the difference between the result (ρ₃) and ρ₂. ④ Hydrofluoric acid and sodium persulfate for digesting dissovled organic silicon to active silicon were added to the water sample, and the mixed solution was digested at 120 ℃ for 30 min in a hydrothermal kettle. The solution obtained was mixed with aluminum chloride, washed, diluted, and done as follow-up steps with ①. The mass concentration of dissolved organic silicon was obtained by the difference between the result (ρ₄) and ρ₃. ⑤ Sodium hydroxide (for digestion of granular silicon and colloidal silicon) and sodium persulfate were added to the water sample, and the mixed solution was digested at 200 ℃ for 120 min in a hydrothermal kettle. The solution obtained was mixed with sulfuric acid washed, diluted, and done as follow-up steps with ④. The mass concentration of granular silicon was obtained by the difference between the result (ρ₅) and ρ₄. The series of standard solutions prepared by SiO₂ datum chemical reagent were detected after treatments with interference masking, digestion and color reaction, and linear relationships obtained between mass of silicon (calculated as SiO₂) and its corresponding absorbance were kept in the range of 500-5 000 μg, with detection limits of silicon (calculated as SiO₂) in the range of 4.0-7.1 mg·L^-1. Tests for accuracy and precision were made on standard solution of silicon at intra-and inter-laboratory. RSDs (n=5) of the determined values of the total silicon from intra-laboratory and inter-laboratory were found in the range of 0.85%-4.5% and 2.1%-5.0%, relative errors were in the range of -7.4%-0.47% and -4.5%--1.7%. Values of test for spiked recovery ranged from 95.8% to 96.8%. The proposed method was applied to the analysis of actual samples, with the contents of active silicon accounted for 94%-97% of that of the total silicon, and it was suggested to remove silicon impurities in the produced water of heavy oil by chemical precipitation.