Method for producing feed-grade calcium hydrophosphate by hydrochloric acid method

Abstract

The invention relates to the field of preparation of calcium hydrophosphate, and discloses a method for producing feed-grade calcium hydrophosphate by a hydrochloric acid method, which comprises the following steps: acidolysis: decomposing ground phosphate rock by hydrochloric acid to obtain acidolysis liquid; secondary iron extraction: adding an extracting agent into the acidolysis solution, and performing secondary counter-current extraction to obtain iron-removed phosphoric acid liquid; secondary extraction: adding an extracting agent into the iron-removed phosphoric acid solution, and carrying out secondary counter-current extraction to obtain organic-phase loaded phosphoric acid and water-phase raffinate; washing is performed; reverse extraction; carrying out neutralization reaction; and drying. The amount of acid added in the acidolysis process is 1.1 times of the theoretical amount, the acid fully reacts with the phosphorite, less acid sludge is generated, and the utilization rate of the phosphorite is high. Meanwhile, an iron resource in the phosphorite can be recycled and converted into ferric trichloride which can be sold as a byproduct, so that the economic benefit is improved, and the environment is protected. The process can reduce the use of calcium carbonate, reduce the emission of carbon dioxide and save the medicament cost; compared with the original process, the total yield is increased from 60% to 70%, and the product quality is higher.

Description

Technical Field

[0001] This application relates to the field of calcium hydrogen phosphate preparation, and more specifically, it relates to a method for producing feed-grade calcium hydrogen phosphate by the hydrochloric acid method. Background Art

[0002] The existing production process flow of feed-grade calcium hydrogen phosphate is as follows: 1. Acidolysis The purpose of acidolysis is to decompose phosphate rock slurry with hydrochloric acid to produce phosphoric acid solution. The reaction equation is: Ca5F(PO4)3 + 10HCl → 3H3PO4 + 5CaCl2 + HF↑ Other impurities in the phosphate rock also undergo chemical reactions with hydrochloric acid during acidolysis, generating corresponding calcium chloride, iron chloride, aluminum chloride, phosphate, silicon tetrafluoride, and fluosilicic acid, etc.

[0003] 2. First-stage neutralization The purpose of the first-stage neutralization is to purify the acidolysis solution and provide qualified mother liquor for the second-stage neutralization. The acidolysis solution is a dilute aqueous solution mainly composed of phosphoric acid and calcium chloride, which contains a small amount of iron and aluminum chlorides, phosphates, fluosilicic acid, and partial free hydrochloric acid. The removal of fluorine is the key, which directly affects the fluorine content of the finished product. Therefore, the acidolysis solution must be purified and defluorinated to meet the production process requirements. The method is: add lime milk to the acidolysis solution for neutralization and defluorination, control the lime addition rate, and analyze the P2O5 / F ratio of the mother liquor to determine the pH of the first-stage neutralization.

[0004] The calcium fluoride precipitate, iron and aluminum phosphate precipitates, and calcium hydrogen phosphate precipitate generated in this process settle together. By analyzing and testing the phosphorus-fluorine ratio of the supernatant layer, when it meets the process production requirements (P2O5 / F ≥ 200), it can be directly used for producing feed-grade calcium hydrogen phosphate without further refining. The thick slurry layer directly enters the fertilizer system for pressure filtration.

[0005] 3. Second-stage neutralization The purpose of the second-stage neutralization: react the refined phosphoric acid solution with lime milk to produce feed-grade calcium hydrogen phosphate. The reaction mechanism is: the refined phosphoric acid is neutralized with lime milk to first generate calcium dihydrogen phosphate monohydrate, and then calcium dihydrogen phosphate monohydrate is neutralized with lime milk to generate precipitated calcium hydrogen phosphate. The reaction equations are: 2H3PO4 + Ca(OH)2 → Ca(H2PO4)2•H2O + H2O Ca(H2PO4)2•H2O + Ca(OH)2 + H2O → 2CaHPO4•2H2O↓ The generated calcium hydrogen phosphate is settled and centrifugally separated. The obtained filter cake is a semi-finished product of feed calcium hydrogen phosphate, and after drying, it is the feed-grade calcium hydrogen phosphate product. The supernatant after neutralization is a calcium chloride aqueous solution, which can be directly sold after three-stage neutralization and sedimentation.

[0006] Problems existing in the prior art are as follows: 1. The total yield is low, only 60%, resulting in a large loss of phosphate rock resources.

[0007] 2. Acidolysis produces more acid residues, and a large amount of white fertilizer is produced in the first-stage neutralization; the acid residues cannot be effectively utilized, and the demand for white fertilizer is small, which is only suitable for specific soil environments.

[0008] 3. During the production process, due to the extremely small calcium carbonate powder, the filter cloth will be blocked, resulting in a large production labor intensity. Summary of the Invention

[0009] The object of the present invention is to provide a method for producing feed-grade dicalcium phosphate by hydrochloric acid method with high efficiency, safety and good processability.

[0010] The object of the present invention is achieved as follows. A method for producing feed-grade dicalcium phosphate by hydrochloric acid method is carried out through the following technological steps for the production of dicalcium phosphate: Step 1, acidolysis: Decompose phosphate rock powder with hydrochloric acid to obtain an acidolysis solution; Step 2, secondary iron extraction: Add extractant No. 1 to the acidolysis solution, and carry out secondary countercurrent extraction to obtain iron-removed phosphoric acid solution; Step 3, secondary extraction: Add extractant No. 2 to the iron-removed phosphoric acid solution, and carry out secondary countercurrent extraction to obtain loaded phosphoric acid in the organic phase and raffinate in the aqueous phase; Step 4, washing: Wash the loaded phosphoric acid by secondary countercurrent washing with the washing solution of the next process to clean the impurities in the loaded organic phase. The washing solution is returned to the extraction process, and the washed organic phase goes to the stripping process; Step 5, stripping: Strip the washed organic phase with demineralized water by four-stage countercurrent extraction to obtain stripping acid. The organic phase is returned to the extraction and directly reused; Step 6, neutralization reaction: React the stripping acid directly with calcium carbonate powder and neutralize to a pH of 3.8 - 5.4, and then centrifuge and filter to obtain semi-finished dicalcium phosphate; Step 7, drying.

[0011] Furthermore, the specific steps of the said Step 1 are as follows: Add phosphate rock powder and 25% hydrochloric acid into the acidolysis tank. The ratio of hydrochloric acid to phosphate rock powder is 1.1 times. Under the condition of a temperature of 20°C - 40°C, stir the two at 300 rpm. The acidolysis time is 0.5 h - 1 h. After filtration, the acidolysis solution is obtained and put into the crude mother liquor tank.

[0012] Furthermore, the specific steps of the said Step 2 are as follows: Add extractant No. 1 into the crude mother liquor tank. Extractant No. 1 is a N235 compound extractant. The phase ratio of the crude mother liquor to extractant No. 1 is 4:1. The process adopts secondary countercurrent extraction. The temperature for secondary iron extraction is 20°C - 40°C, and the extraction time is 0.5 h. The liquid after iron extraction is iron-removed phosphoric acid, which is put into the iron-removed phosphoric acid tank.

[0013] Further, the specific steps of Step 3 are as follows: Add Extractant 2 into the iron-removing phosphoric acid tank containing iron-removing phosphoric acid. Extractant 2 is a TBP compounded extractant. The ratio of iron-removing phosphoric acid to Extractant 2 is 1:4. Adopt two-stage countercurrent extraction. The temperature of the two-stage countercurrent extraction is 50°C, and the extraction time is 0.5 h to obtain loaded phosphoric acid in the organic phase and raffinate in the aqueous phase.

[0014] Further, the specific steps of Step 4 are as follows: Wash the loaded phosphoric acid with the washing acid from the next process. The ratio is 10:1, the temperature is 50°C, and the washing time is 0.5 h. Adopt two-stage countercurrent washing to clean the impurities in the loaded organic phase. The washing solution is returned to the extraction process, and the washed organic phase goes to the stripping process.

[0015] Further, the specific steps of Step 5 are as follows: Strip the washed organic phase with demineralized water. The ratio is 5:1, the temperature is 60°C, and adopt four-stage countercurrent extraction to obtain stripping acid. The organic phase is returned to extraction and directly reused.

[0016] Further, in Step 2, Extractant 1 includes N235, Alcohol 1, and sulfonated kerosene, and the volume ratio is 1 - 5:1 - 5:5 - 8.

[0017] Further, in Step 2, Alcohol 1 in the components of Extractant 1 is one or more of isopropyl alcohol, diisopropyl ether, cyclohexanol, n-octanol, and isooctanol.

[0018] Further, in Step 3, Extractant 2 includes TBP, Alcohol 2, and sulfonated kerosene, and the volume ratio is 4 - 8:1 - 5:1 - 5.

[0019] Further, in Step 2, Alcohol 2 in the components of Extractant 2 is one or more of isopropyl alcohol, diisopropyl ether, cyclohexanol, n-octanol, and isooctanol. In summary, the present application has the following beneficial effects: 1. The amount of acid added during the acidolysis process is 1.1 times the theoretical amount, which reacts fully with the phosphate rock, produces less acid residue, and has a high utilization rate of phosphate rock.

[0020] 2. It can recover the iron resources in the phosphate rock, convert them into ferric chloride, which can be sold as a by-product, improving economic benefits while protecting the environment.

[0021] 3. This process can reduce the use of calcium carbonate, reduce carbon dioxide emissions, and save the cost of chemicals; the total yield is increased from 60% to 70% compared with the original process, and the product quality is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a flow chart of the process of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0023] The structure and effects of the present application will be further described in detail below in conjunction with embodiments. It can be understood that the specific embodiments described herein are only used to explain the invention, rather than limiting the invention. In addition, it should be noted that for the convenience of description, only parts related to the invention are shown in the drawings, rather than all the structures.

[0024] Embodiment 1

[0025] As Figure 1 shown, a method for producing feed-grade calcium hydrogen phosphate by the hydrochloric acid method, which produces calcium hydrogen phosphate through the following technological steps: Step 1, acidolysis: Add phosphate rock powder and 25% hydrochloric acid into the acidolysis tank. The ratio of hydrochloric acid to phosphate rock powder is 1.1 times. At a temperature of 30°C, stir the two at 300 rpm. The acidolysis time is 1 h. After filtration, the acidolysis solution is obtained and put into the crude mother liquor tank. Step 2, secondary iron extraction: Add the No. 1 extractant into the crude mother liquor tank. The No. 1 extractant is a N235 compound extractant. The phase ratio of the crude mother liquor to the No. 1 extractant is 4:1. The process adopts secondary countercurrent extraction. The temperature of secondary iron extraction is 30°C, and the extraction time is 0.5 h. The liquid after iron extraction is iron-removed phosphoric acid, which is put into the iron-removed phosphoric acid tank. Step 3, secondary extraction: Add the No. 2 extractant into the iron-removed phosphoric acid tank containing iron-removed phosphoric acid. The No. 2 extractant is a TBP compound extractant. The phase ratio of iron-removed phosphoric acid to the No. 2 extractant is 1:4. Adopt secondary countercurrent extraction. The temperature of secondary countercurrent extraction is 50°C, and the extraction time is 0.5 h to obtain the loaded phosphoric acid in the organic phase and the aqueous phase raffinate. Step 4, washing: Wash the loaded phosphoric acid with the washing acid from the next process. The phase ratio is 10:1, the temperature is 50°C, and the washing time is 0.5 h. Adopt secondary countercurrent washing to clean the impurities in the loaded organic phase. The washing solution returns to the extraction process, and the washed organic phase goes to the stripping process.

[0026] Step 5, stripping: Strip the washed organic phase with demineralized water. The phase ratio is 5:1, the temperature is 60°C, and adopt four-stage countercurrent extraction to obtain the stripping acid. The organic phase returns to the extraction and is directly reused.

[0027] Step 6, neutralization reaction: React the stripping acid directly with calcium carbonate powder and neutralize to a pH of 3.8 - 5.4, and centrifugally filter to obtain semi-finished calcium hydrogen phosphate. Step 7, drying: Place the semi-finished calcium hydrogen phosphate at an ambient temperature of 30°C, and after air-drying, it is a feed-grade phosphoric acid product.

[0028] In the said step 2, the components of the No. 1 extractant are N235 + No. 1 alcohol (isopropanol) + sulfonated kerosene, and the volume ratio is 1:1:5.

[0029] In Step 3, the components of the 2# extractant are TBP + 2# alcohol (isopropanol) + sulfonated kerosene, and the volume ratio is 4:1:1.

[0030] Example 2

[0031] As Figure 1 shown, a method for producing feed-grade calcium hydrogen phosphate by the hydrochloric acid method, which produces calcium hydrogen phosphate through the following technological steps: Step 1, acidolysis: Add phosphate rock powder and 25% hydrochloric acid into the acidolysis tank. The ratio of hydrochloric acid to phosphate rock powder is 1.1 times. At a temperature of 30°C, stir the two at 300 rpm for 1 hour of acidolysis time. After filtration, the acidolysis solution is obtained and put into the crude mother liquor tank. Step 2, secondary iron extraction: Add the 1# extractant into the crude mother liquor tank. The 1# extractant is a N235 compound extractant. The phase ratio of the crude mother liquor to the 1# extractant is 4:1. The process adopts secondary countercurrent extraction. The temperature of secondary iron extraction is 30°C, and the extraction time is 0.5 hour. The liquid after iron extraction is iron-removed phosphoric acid, which is put into the iron-removed phosphoric acid tank. Step 3, secondary extraction: Add the 2# extractant into the iron-removed phosphoric acid tank containing iron-removed phosphoric acid. The 2# extractant is a TBP compound extractant. The phase ratio of iron-removed phosphoric acid to the 2# extractant is 1:4. Secondary countercurrent extraction is adopted. The temperature of secondary countercurrent extraction is 50°C, and the extraction time is 0.5 hour to obtain the loaded phosphoric acid in the organic phase and the aqueous phase raffinate. Step 4, washing: Wash the loaded phosphoric acid with the washing acid from the next process. The phase ratio is 10:1, the temperature is 50°C, and the washing time is 0.5 hour. Secondary countercurrent washing is carried out to clean the impurities in the loaded organic phase. The washing liquid returns to the extraction process, and the washed organic phase goes to the stripping process.

[0032] Step 5, stripping: Strip the washed organic phase with deionized water. The phase ratio is 5:1, the temperature is 60°C, and four-stage countercurrent extraction is carried out to obtain the stripping acid. The organic phase returns to the extraction and is directly reused.

[0033] Step 6, neutralization reaction: React the stripping acid directly with calcium carbonate powder and neutralize it to a pH of 3.8 - 5.4, and then carry out centrifugal filtration to obtain semi-finished calcium hydrogen phosphate. Step 7, drying: Place the semi-finished calcium hydrogen phosphate at an ambient temperature of 30°C, and after air-drying, it is a feed-grade phosphoric acid product.

[0034] In Step 2, the components of the 1# extractant are N235 + 1# alcohol (cyclohexanol) + sulfonated kerosene, and the volume ratio is 1:5:8.

[0035] In Step 3, the components of the 2# extractant are TBP + 2# alcohol (n-octanol) + sulfonated kerosene, and the volume ratio is 4:5:1.

[0036] Example 3

[0037] As Figure 1 shown, a method for producing feed-grade calcium hydrogen phosphate by the hydrochloric acid method, and the production of calcium hydrogen phosphate is carried out through the following technological steps: Step 1, acidolysis: Add phosphate rock powder and 25% hydrochloric acid into the acidolysis tank. The ratio of hydrochloric acid to phosphate rock powder is 1.1 times. At a temperature of 30 °C, stir the two at 300 rpm. The acidolysis time is 1 h. After filtration, the acidolysis solution is obtained and placed in the crude mother liquor tank; Step 2, secondary iron extraction: Add the No. 1 extractant into the crude mother liquor tank. The No. 1 extractant is a N235 compound extractant. The phase ratio of the crude mother liquor to the No. 1 extractant is 4:1. The process adopts secondary countercurrent extraction. The temperature of secondary iron extraction is 30 °C, and the extraction time is 0.5 h. The liquid after iron extraction is iron-removed phosphoric acid, which is placed in the iron-removed phosphoric acid tank; Step 3, secondary extraction: Add the No. 2 extractant into the iron-removed phosphoric acid tank containing iron-removed phosphoric acid. The No. 2 extractant is a TBP compound extractant. The phase ratio of iron-removed phosphoric acid to the No. 2 extractant is 1:4. Secondary countercurrent extraction is adopted. The temperature of secondary countercurrent extraction is 50 °C, and the extraction time is 0.5 h to obtain the loaded phosphoric acid in the organic phase and the aqueous phase raffinate; Step 4, washing: Wash the loaded phosphoric acid with the washing acid from the next process. The phase ratio is 10:1, the temperature is 50 °C, and the washing time is 0.5 h. Secondary countercurrent washing is carried out to clean the impurities in the loaded organic phase. The washing liquid is returned to the extraction process, and the washed organic phase goes to the stripping process.

[0038] Step 5, stripping: Strip the washed organic phase with deionized water. The phase ratio is 5:1, the temperature is 60 °C, and four-stage countercurrent extraction is carried out to obtain the stripping acid. The organic phase is returned to the extraction and directly reused.

[0039] Step 6, neutralization reaction: React the stripping acid directly with calcium carbonate powder and neutralize to a pH of 3.8 - 5.4. Centrifugal filtration gives the semi-finished calcium hydrogen phosphate; Step 7, drying: Place the semi-finished calcium hydrogen phosphate at an ambient temperature of 30 °C. After air-drying, it is a feed-grade phosphoric acid product.

[0040] In the said Step 2, the components of the No. 1 extractant are N235 + No. 1 alcohol (cyclohexanol) + sulfonated kerosene, and the volume ratio is 5:5:8.

[0041] In the said Step 3, the components of the No. 2 extractant are TBP + No. 2 alcohol (n-octanol) + sulfonated kerosene, and the volume ratio is 8:5:5.

[0042] Comparative Example 1 Adopt the conventional hydrochloric acid method for producing calcium hydrogen phosphate described in the background technology. The specific steps are as follows: Acidolysis: The phosphate rock powder reacts with excessive hydrochloric acid (1.3 times the theoretical amount) at a temperature of 30 °C for 1 h.

[0043] First-stage neutralization: Add lime milk to adjust the pH to 2.0 - 2.5, and after defluorination, sedimentation and separation are carried out (P2O5 / F ≥ 200).

[0044] Second-stage neutralization: Neutralize with lime milk to a pH of 3.8 - 5.4 to form calcium hydrogen phosphate precipitate.

[0045] Post-treatment: Centrifuge and dry to obtain the finished product.

[0046] Performance detection (1) Detect the total yield according to the phosphorus element mass balance method (ICP - OES); (2) Determine the product purity according to the XRD quantitative analysis method.

[0047] The results are shown in the following table: Total yield (%) <![CDATA[Product purity (CaHPO4·2H2O%)]]> By-product Example 1 70.6 98.3 <![CDATA[FeCl3]]> Example 2 72.4 98.9 <![CDATA[FeCl3]]> Example 3 71.6 98.2 <![CDATA[FeCl3]]> Comparative Example 1 59.3 92.4 White fertilizer The beneficial effects of the present invention are as follows: In the acidolysis process of the process of the present invention, the amount of acid added is 1.1 times the theoretical amount, which reacts fully with the phosphate rock, produces less acid residue, and has a high utilization rate of phosphate rock. At the same time, the iron resources in the phosphate rock can be recovered and converted into ferric chloride, which can be sold as a by-product, improving economic benefits and protecting the environment. Through this process, the use of calcium carbonate can be reduced, carbon dioxide emissions can be reduced, and the reagent cost can be saved; the total yield is increased from 60% to 70% compared with the original process, and the product quality is higher.

[0048] This specific embodiment is only an explanation of the present application, and it does not limit the present application. Those skilled in the art can make modifications without creative contributions to this embodiment according to needs after reading this specification, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. A method for producing feed-grade calcium hydrogen phosphate by the hydrochloric acid method, characterized in that, It includes the following steps: Step 1, acid hydrolysis: Decompose phosphate rock powder with hydrochloric acid to obtain an acid hydrolysis solution; Step 2, secondary iron extraction: Add Extractant 1 to the acid hydrolysis solution, and perform secondary countercurrent extraction to obtain iron-removed phosphoric acid solution; Step 3, secondary extraction: Add Extractant 2 to the iron-removed phosphoric acid solution, and perform secondary countercurrent extraction to obtain loaded phosphoric acid in the organic phase and raffinate in the aqueous phase; Step 4, washing: Wash the loaded phosphoric acid with the washing acid from the next process through secondary countercurrent washing to clean the impurities in the loaded organic phase. The washing solution is returned to the extraction process, and the washed organic phase goes to the stripping process; Step 5, stripping: Strip the washed organic phase with demineralized water through four-stage countercurrent extraction to obtain stripped acid. The organic phase is returned to the extraction process for direct reuse; Step 6, neutralization reaction: React the stripped acid directly with calcium carbonate powder and neutralize it to a pH of 3.8 - 5.4, then perform centrifugal filtration to obtain semi-finished calcium hydrogen phosphate; Step 7, drying.

2. The method for producing feed-grade dicalcium phosphate by the hydrochloric acid method according to claim 1, characterized in that The specific steps of the said Step 1 are as follows: Add phosphate rock powder and 25% hydrochloric acid into the acid hydrolysis tank. The ratio of hydrochloric acid to phosphate rock powder is 1.1 times. Under the condition of a temperature of 20°C - 40°C, stir the two at 300 rpm. The acid hydrolysis time is 0.5 h - 1 h. After filtration, the acid hydrolysis solution is obtained and put into the crude mother liquor tank.

3. The method for producing feed-grade dicalcium phosphate by the hydrochloric acid method according to claim 1, characterized in that, The specific steps of the said Step 2 are as follows: Add Extractant 1 into the crude mother liquor tank. Extractant 1 is a N235 compound extractant. The phase ratio of the crude mother liquor to Extractant 1 is 4:

1. The process adopts secondary countercurrent extraction. The temperature for secondary iron extraction is 20°C - 40°C, and the extraction time is 0.5 h. The liquid after iron extraction is iron-removed phosphoric acid, which is put into the iron-removed phosphoric acid tank.

4. The method for producing feed-grade dicalcium phosphate by the hydrochloric acid method according to claim 1, wherein The specific steps of the said Step 3 are as follows: Add Extractant 2 into the iron-removed phosphoric acid tank containing iron-removed phosphoric acid. Extractant 2 is a TBP compound extractant. The phase ratio of iron-removed phosphoric acid to Extractant 2 is 1:

4. Adopt secondary countercurrent extraction. The temperature for secondary countercurrent extraction is 50°C, and the extraction time is 0.5 h to obtain loaded phosphoric acid in the organic phase and raffinate in the aqueous phase.

5. The method for producing feed-grade dicalcium phosphate by the hydrochloric acid method according to claim 1, wherein, The specific steps of the said Step 4 are as follows: Wash the loaded phosphoric acid with the washing acid from the next process. The phase ratio is 10:1, the temperature is 50°C, and the washing time is 0.5 h. Perform secondary countercurrent washing to clean the impurities in the loaded organic phase. The washing solution is returned to the extraction process, and the washed organic phase goes to the stripping process.

6. The method for producing feed-grade dicalcium phosphate by the hydrochloric acid method according to claim 1, wherein, The specific steps of the said Step 5 are as follows: Strip the washed organic phase with demineralized water. The phase ratio is 5:1, the temperature is 60°C, and perform four-stage countercurrent extraction to obtain stripped acid. The organic phase is returned to the extraction process for direct reuse.

7. The method for producing feed-grade dicalcium phosphate by the hydrochloric acid method according to claim 1, characterized in that, In the said Step 2, Extractant 1 includes N235, Alcohol 1, and sulfonated kerosene, and the volume ratio is 1 - 5:1 - 5:5 - 8.

8. The method for producing feed-grade dicalcium phosphate by the hydrochloric acid method according to claim 7, characterized in that, In the said Step 2, Alcohol 1 in the components of Extractant 1 is one or several of isopropanol, diisopropyl ether, cyclohexanol, n-octanol, and isooctanol.

9. The method for producing feed-grade dicalcium phosphate by the hydrochloric acid method according to claim 1, characterized in that, In the said Step 3, Extractant 2 includes TBP, Alcohol 2, and sulfonated kerosene, and the volume ratio is 4 - 8:1 - 5:1 - 5.

10. The method for producing feed-grade dicalcium phosphate by the hydrochloric acid method according to claim 9, characterized in that, In the said Step 2, Alcohol 2 in the components of Extractant 2 is one or several of isopropanol, diisopropyl ether, cyclohexanol, n-octanol, and isooctanol.

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