CN1580196A - Dearsenicating agent for removing high boiling point arsonium compound in liquid-state petroleum hydrocarbon at low temperature and normal temperature - Google Patents

Abstract

The invention is a kind of agent which is used to deprive the arsenide of high boiling point in petroleum hydrocarbon at low or normal temperature. The agent contains a type of carrying agent, which loads helpactive component of one or two kinds of rare earth metal or noble metal or their oxide. The agent can deprive the arsenide of high boiling point in petroleum hydrocarbon at low or normal temperature. The preparation method is easy and safe, besides, the invention will not produce devil liquor containing arsenic and pollute environment. Invention name

Description

Arsenic removal agent for removing high boiling point arsenic compounds in liquid petroleum hydrocarbons at low or normal temperature

technical field

The invention relates to an arsenic-removing agent for removing high-boiling-point arsenic compounds in liquid petroleum hydrocarbons at low temperature or normal temperature.

Background technique

Arsenic compounds widely exist in petroleum hydrocarbons. They have a permanent poisoning effect on many catalysts in petroleum hydrocarbon processing, seriously affecting the activity and service life of catalysts. Therefore, it is of great significance to remove arsenic compounds in petroleum hydrocarbons.

Arsenic compounds in petroleum hydrocarbons are mainly trivalent organic arsine complexes, and organic arsine complexes with different boiling points will enter into various fractions of crude oil fractionation respectively. In addition to a certain amount of low-boiling arsenic compounds such as AsH ₃ and CH ₃ AsH ₂ , liquid petroleum hydrocarbons also contain a considerable amount of high-boiling point arsenic compounds such as As(CH ₃ ) ₃ , As(C ₂ H ₅ ) ₃ and so on. The higher the boiling point of the arsenide or the longer the chain length of the hydrocarbon group, the less likely it is to be removed, and the higher the requirements for the arsenic removal agent.

At present, the commonly used methods for removing arsenic from liquid hydrocarbons are:

1. Oxygen dearsenization

Potassium permanganate and cumene hydroperoxide (CHP) are used as oxidants to treat petroleum hydrocarbons, and then the inorganic arsenic compounds are removed by water washing. This method has a large amount of wastewater treatment and serious environmental pollution.

2. Catalytic Hydrodearsenization

This method needs to be operated under high temperature and high pressure, the operation process is complicated, the operation cost is high, and it is easy to coke, resulting in a short service life.

3. Arsenic removal by adsorption

This method uses silica-alumina pellets and silica-alumina pellets loaded with copper sulfate to remove trace arsenides in liquid petroleum hydrocarbons. For most applications, the adsorption and arsenic removal process is simple, but it is difficult to remove high-boiling point arsenides , the depth of arsenic removal is not high, the adsorption capacity of arsenic is small, and the service life is short.

US patents US 5064626, US 5085844, US 5096681, and US 5096682 involve the removal of trialkylarsine (trimethylarsine) and related arsenic removal agents, but the above patent documents do not involve liquid petroleum hydrocarbon systems.

Chinese patent CN 1030440A relates to the process of removing phosphorus and arsenic compounds from normally liquid hydrocarbons. Under heating conditions, the liquid hydrocarbons are contacted with a catalyst containing at least 50% metallic nickel. The process can be applied For the purification of gasoline and naphtha. At the same time, Chinese patent CN 1136070A relates to a preparation method of a nickel-based arsenic removal catalyst used in petroleum distillate oil containing arsenic liquid hydrocarbons. In addition, Chinese patent CN 1113261A discloses a nickel-based arsenic removal catalyst, which can effectively remove arsenic and/or phosphorus from liquid petroleum hydrocarbons. US2003/0111391A1 also discloses an arsenic removal catalyst containing VIB groups such as Mo and VIII groups such as Ni, which is used for the removal of arsenic from liquid petroleum hydrocarbons. Those skilled in the art know that the above process and/or arsenic removal agent are only suitable for the removal of arsenic from liquid hydrocarbons under high temperature and hydrogen-facing conditions.

Chinese patent CN 1197052A discloses a method for removing arsenic from liquid hydrocarbon raw materials. The arsenic removal agent used in the method is copper oxide or copper sulfide deposited on a carrier, and the method is performed at a low temperature without hydrogen , Operate under low pressure conditions. The patent proposes a protected arsenic removal agent, the preparation of which involves a complex sulfidation process, so the active component of the arsenic removal is at least partly present as copper sulfide. Based on the analysis of the technical data provided by the patent literature, the removal effect of simple copper compounds as active components on high-boiling arsenides is not ideal, and the arsenic capacity of the arsenic removal agent is less than 0.1%.

Contents of the invention

The object of the present invention is to provide an arsenic removal agent with good removal performance for high-boiling arsenic compounds in petroleum hydrocarbons, which can remove arsenic compounds in petroleum hydrocarbons more smoothly under normal temperature or low temperature (<100°C) conditions.

The low-temperature or normal-temperature arsenic removal agent for removing high-boiling-point arsenic compounds in liquid petroleum hydrocarbons contains a carrier, and the carrier is loaded with one to three main active components of transition metals or their oxides, and simultaneously loaded with one to three kinds of transition metals or their oxides. Co-active components of two rare earth metals and/or noble metals or their oxides.

The main active component transition metal or its oxide loaded on the carrier accounts for 0.5-50% by weight of the total amount of the arsenic removal agent, preferably 2-20%.

The auxiliary active component rare earth metal and/or noble metal or their oxides loaded on the carrier accounts for 0.0005-10% by weight of the total amount of the arsenic-removing agent, preferably 0.005-5%.

In the present invention, the transition metal as the main active component is a fourth period transition metal. The rare earth metal used as the active component is selected from one of lanthanum, cerium and samarium, and the noble metal is selected from one or both of gold, silver, rhodium and palladium.

The average pore diameter of the carrier is 1-100 nm, preferably 3-20 nm; the pore volume is 0.1-1.5 mL/g, preferably 0.3-1.0 mL/g.

The carrier is preferably selected from ZSM-5 molecular sieve, mesoporous molecular sieve, USY molecular sieve, activated carbon, aluminum oxide (Al ₂ O ₃ ), silicon dioxide (SiO ₂ ), zinc oxide (ZnO), copper oxide (CuO), oxide One or a mixture of chromium (Cr ₂ O ₃ ), titanium dioxide (TiO ₂ ), silicon aluminum oxide (Al ₂ O ₃ -SiO ₂ ).

The active component of the arsenic removal agent of the invention does not contain sulfide, but the arsenic removal performance is not affected by the sulfide in liquid petroleum hydrocarbons.

The arsenic removal agent of the present invention is suitable for removing arsenic in liquid petroleum hydrocarbons such as liquid alkanes, alkenes, alkynes, aromatics, or liquid organic mixtures containing the above-mentioned compounds at low temperature (<100°C) or normal temperature and pressure. compounds. Liquid petroleum hydrocarbons may contain low-boiling organic or inorganic arsenic compounds that are gaseous at normal temperature and pressure in addition to high-boiling arsenic compounds that are liquid or solid at normal temperature and pressure.

The arsenic capacity of the arsenic removal agent of the invention is above 1.0%, and under certain process conditions, the arsenic content of raw materials can be reduced from as high as 500 ppb to below 10 ppb.

Compared with the prior art, the present invention has the following advantages:

1. The arsenic removal agent of the present invention has better removal performance for high-boiling arsenic compounds, such as triphenylarsine and triethylarsine, at normal temperature or low temperature, and can more thoroughly remove arsenic in petroleum hydrocarbons compounds.

2. The arsenic removal agent of the present invention is used under the condition of low temperature or normal temperature without hydrogen exposure, and the operation is simpler, the conditions are more favorable, and the safety is better.

3. The arsenic-removing agent of the present invention will not produce arsenic-containing waste liquid and pollute the environment during use.

Detailed ways

The following examples are used to further illustrate the present invention, but the present invention is by no means limited to these examples.

Example 1

Take 200 grams of silica (SiO ₂ ) carrier with an average pore diameter of 10-12 nm and a pore volume of 0.8 mL/g, and immerse it in 300 ml of a mixed solution of Fe(NO ₃ ) ₃ and Pd(NO ₃ ) ₂ at a certain concentration, After staying overnight, dry it on an electric furnace with a small fire, further dry it at 120°C, and then burn it in a high-temperature furnace at 400°C for 12 hours to prepare arsenic removal agents numbered 1 to 11 (see Table 1) , stored in a vacuum desiccator for later use.

Take 50 grams of arsenic removal agents numbered 1 to 11 respectively, fill them in a fixed-bed reactor with an inner diameter of 33mm, activate them in a nitrogen atmosphere at 150-300°C for 2 hours, cool down to below 50°C, and then measure Pump into naphtha (sulfur 300ppm) equipped with 500ppb arsenic (existing in the form of AsPh ₃ ), keep the liquid space velocity at 2.5h ^-1 , and after continuous treatment for 200 hours, detect the arsenic concentration at the outlet. The test results are shown in Table 1 .

Table 1 serial number Fe ₂ O ₃ (%) Pd(%) Concentration before arsenic removal (ppb) Concentration after arsenic removal (ppb) 1 0.5 0.05 500 <20 2 2.0 0.05 500 <10 3 10.0 0.05 500 <5 4 20.0 0.05 500 <5 5 30.0 0.05 500 <10 6 50.0 0.05 500 <20 7 10.0 0.0005 500 <20 8 10.0 0.005 500 <10 9 10.0 0.5 500 <5 10 10.0 5.0 500 <5 11 10.0 10.0 500 <5

Example 2

Add aluminum nitrate (Al(NO ₃ ) ₃ 9H ₂ O) 187.6 grams (0.5mol) and zinc nitrate (Zn(NO ₃ ) ₂ 6H ₂ O) 59.5 grams (0.2mol) in the reactor, copper nitrate ( Cu(NO ₃ ) ₂ ·3H ₂ O) 40.6 g and silver nitrate (AgNO ₃ ) 2.06 g, then add 100 mL of deionized water, stir well to dissolve, keep the temperature at 50-55°C, add dropwise 40wt% Na ₂ CO ₃ solution to The pH value of the solution is between 7.5 and 9, and after aging for 0.5 hour, the solid material is obtained by centrifugation. The solid material was reslurried with deionized water to fully remove soluble inorganic salts, dried at 120°C after molding, and then burned in a high-temperature furnace at 400°C for 12 hours, and stored in a vacuum desiccator for future use.

Get 50 grams of the obtained arsenic removal agent, fill and pretreat the arsenic removal agent according to the method of Example 1, then inject the naphtha with 500ppb arsenic (existing in the form of _AsPh ) with a metering pump, and keep the liquid space velocity at 2.5 h ^-1 , after 200 hours of continuous treatment, the outlet arsenic concentration is less than 5.0ppb.

Example 3

Take 50 grams of the arsenic removal agent prepared according to the method in Example 2, fill it in a fixed-bed reactor with an inner diameter of 33 mm, and use hydrogen-nitrogen mixed gas (H ₂ /N ₂ (v/v)=1 : 1) After reducing for 4 hours, lower the temperature to below 50°C. Then use a metering pump to inject naphtha with 500ppb arsenic (in the form of AsPh ₃ ), keep the liquid space velocity at 2.5h ^-1 , and after 200 hours of continuous treatment, the outlet arsenic concentration is less than 5.0ppb.

Example 4

Weigh 3.51 grams of cerium nitrate and 110 grams of 50% manganese nitrate solution, dissolve them in 100 mL of deionized water, add 97 grams of silicon-aluminum oxide (Al ₂ O ₃ -SiO ₂ ) carrier, soak for 12 hours, and bake on a low heat in an electric furnace Dry it, and then burn it in a high-temperature furnace at 500°C to obtain an arsenic removal agent. Take 50 grams of the arsenic removal agent to evaluate the arsenic removal activity according to the method of Example 1. After 200 hours of continuous treatment, the outlet arsenic concentration has dropped below 10.0 ppb.

Example 5

Weigh 6.72 grams of silver nitrate (AgNO ₃ ) and 36.75 grams of copper sulfate, dissolve them in 100 mL of deionized water, add 97 grams of alumina (Al ₂ O ₃ ) carrier and immerse them for 12 hours, dry them on a low fire in an electric furnace, and then dry them at 500 Decompose silver nitrate by burning and decomposing silver nitrate in a high temperature furnace to obtain arsenic removal agent.

Get 50 grams of the obtained arsenic-removing agent, fill and process the arsenic-removing agent according to Example 1, then pour in naphtha with 500ppb arsenic (existing in the form of _AsPh3 ) with a metering pump, and keep the liquid space velocity at ^{2.0h- 1.} After 500 hours of continuous treatment, the outlet arsenic concentration is less than 5.0ppb.

Example 6

Weigh 47.2 grams of copper nitrate trihydrate and 0.25 grams of lanthanum nitrate and dissolve them in 100 mL of deionized water, add 97 grams of silicon dioxide (SiO ₂ ) carrier and soak for 12 hours, dry on a small fire in an electric furnace, and then soak to 100 mL with a concentration of 20 % ferric nitrate solution, dried in a low fire and burned in a high temperature furnace at 500°C to obtain the arsenic removal agent. Take 50 grams of the arsenic removal agent to evaluate the arsenic removal activity according to the method in Example 1. After 200 hours of continuous treatment, the arsenic concentration in the solution dropped from 500 ppb to less than 10.0 ppb.

Example 7

Get 50 grams of the arsenic removal agent gained in Example 6, fill, pretreat and evaluate the arsenic removal activity according to the method of Example 2, and after continuous treatment for 250 hours under the condition of liquid space velocity 3.0h ^-1 , the solution arsenic concentration is by 500ppb down to less than 5.0ppb.

Example 8

Weigh 39.72 grams of copper acetate (Cu(OOCCH ₃ ) ₂ ·H ₂ O) and 0.012 grams of RhCl ₃ and dissolve them in 100 mL of deionized water, add 97 grams of silicon dioxide (SiO ₂ ) carrier and soak for 12 hours, and place on a small fire in an electric furnace Dry it, and then burn it in a high-temperature furnace at 300°C to decompose manganese acetate to obtain an arsenic removal agent. Take 50 grams of the arsenic removal agent to evaluate the arsenic removal activity according to the method of Example 1. After 200 hours of continuous treatment, the arsenic concentration dropped from 500 ppb to less than 3.0 ppb.

Claims (10)

1. An arsenic removal agent for removing high-boiling arsenic compounds in liquid petroleum hydrocarbons at low temperature or normal temperature, including a carrier, characterized in that: the carrier is loaded with one to three transition metals or their oxides, and simultaneously loaded One to two rare earth metals and/or noble metals or their oxides. 2. The arsenic removal agent according to claim 1, characterized in that the weight percentage of the transition metals or oxides thereof supported on the carrier in the total amount of the arsenic removal agent is 0.5-50%. 3. The arsenic-removing agent according to claim 1, characterized in that the weight percentage of transition metals or oxides thereof loaded on the carrier in the total amount of the arsenic-removing agent is 2-20%. 4. The arsenic removal agent according to claim 1, characterized in that the weight percentage of the rare earth metals and/or noble metals or their oxides loaded on the carrier in the total amount of the arsenic removal agent is 0.0005-10%. 5. The arsenic removal agent according to claim 1, characterized in that the weight percentage of the rare earth metals and/or noble metals or their oxides loaded on the carrier in the total amount of the arsenic removal agent is 0.005-5%. 6. The arsenic removal agent according to claim 1, characterized in that the transition metal is a transition metal of the fourth period. 7. The arsenic removal agent according to claim 1, characterized in that the rare earth metal is selected from lanthanum, cerium and samarium, and the noble metal is selected from gold, silver, rhodium and palladium. 8. The arsenic-removing agent according to claims 1-5, characterized in that: the average pore diameter of the arsenic-removing agent is 1-100 nm, and the pore volume is 0.1-1.5 mL/g. 9. The arsenic-removing agent according to claims 1-5, characterized in that: the average pore diameter of the arsenic-removing agent is 3-20 nm, and the pore volume is 0.3-1.0 mL/g. 10. The arsenic removal agent according to claims 1 to 5, characterized in that the carrier is selected from ZSM-5 molecular sieve, mesoporous molecular sieve, USY molecular sieve, activated carbon, alumina, silicon dioxide, zinc oxide, copper oxide , chromium oxide, titanium dioxide, silicon aluminum oxide or a mixture of two.