Method of removing hydrogen peroxide from sulfuric acid

Abstract

A method of removing hydrogen peroxide from sulfuric acid includes the following steps: First step of pouring the sulfuric acid having 0.1 wt % to 10 wt % of hydrogen peroxide into a vessel. Second step of adding a catalyst containing copper and a copper compound to the vessel to undergo a reaction with the sulfuric acid to remove the hydrogen peroxide from the sulfuric acid, to generate heat, and to generate metal ions in the sulfuric acid. Third step of activating a cooling device to cool the vessel to a predetermined temperature range. Fourth step of adding hydrogen sulfide to the vessel to undergo a reaction with the metal ions to generate metallic sulfide and metal free sulfuric acid. Fifth step of purifying the metallic sulfide and the metal free sulfuric acid to obtain purified metallic sulfide and purified sulfuric acid as products.

Claims

1. A method of removing hydrogen peroxide from sulfuric acid, comprising the steps of: (i) pouring the sulfuric acid (H.sub.2SO.sub.4) having 0.1 wt % to 10 wt % of hydrogen peroxide (H.sub.2O.sub.2) into a vessel; (ii) adding a catalyst containing copper and a copper compound to the vessel to undergo a reaction with the sulfuric acid (H.sub.2SO.sub.4) to remove the hydrogen peroxide (H.sub.2O.sub.2) from the sulfuric acid (H.sub.2SO.sub.4), to generate heat, and to generate metal ions in the sulfuric acid (H.sub.2SO.sub.4); (iii) activating a cooling device to cool the vessel to a predetermined temperature range; (iv) adding hydrogen sulfide (H.sub.2S) to the vessel to undergo a reaction with the metal ions to generate metallic sulfide and metal free sulfuric acid (H.sub.2SO.sub.4); and (v) purifying the metal free sulfuric acid (H.sub.2SO.sub.4) to obtain purified metallic sulfide and purified sulfuric acid (H.sub.2SO.sub.4) as products.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. 1 is a flowchart of a method of removing hydrogen peroxide from sulfuric acid according to the invention; and

[0012] FIG. 2 is a table of test reports regarding the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0013] Referring to FIG. 1, a method 1 of removing hydrogen peroxide from sulfuric acid in accordance with the invention is illustrated and comprises the steps of S1 pouring the sulfuric acid (H.sub.2SO.sub.4) having 0.1 wt % to 10 wt % of hydrogen peroxide (H.sub.2O.sub.2) into a vessel; S2 adding a catalyst containing copper and a copper compound (e.g., cupric oxide (CuO)) to the vessel to undergo a reaction with the sulfuric acid (H.sub.2SO.sub.4) to remove the hydrogen peroxide (H.sub.2O.sub.2) from the sulfuric acid (H.sub.2SO.sub.4), to generate heat, and to generate metal (e.g., copper (Cu)) ions in the sulfuric acid (H.sub.2SO.sub.4); S3 activating a cooling device to cool the vessel to a predetermined temperature range; S4 adding hydrogen sulfide (H.sub.2S) to the vessel to undergo a reaction with the metal ions to generate metallic sulfide (e.g., copper (II) sulfide (CuS)) (e.g., removing copper ions) and metal free sulfuric acid (H.sub.2SO.sub.4); and S5 purifying the metal free sulfuric acid (H.sub.2SO.sub.4) to obtain purified metallic sulfide and purified diluted sulfuric acid (H.sub.2SO.sub.4) as products.

[0014] A portion of expression of step S2 is below.

CuO.sub.(s)+H.sub.2SO.sub.4(l).fwdarw.CuSO.sub.4(l)+H.sub.2O.sub.(l)

2H.sub.2O.sub.2(l).sup.Cu+.fwdarw.2H.sub.2O.sub.(l)+O.sub.2(g)

[0015] Expression of step S4 is below.

H.sub.2S.sub.(g)+CuSO.sub.4(l).fwdarw.CuS.sub.(s)↓+H.sub.2SO.sub.4(l)

[0016] It is noted that great heat is generated when sulfuric acid (H.sub.2SO.sub.4) undergoes a chain reaction with the catalyst (e.g., cupric oxide (CuO)). The heat generation process continues until the materials involved in the reaction are consumed. This is very dangerous because the vessel and associated devices can be damaged or even causes explosion. Thus, a cooling device is activated to cool the vessel to 60° C.-90° C. in step S3 so that the method 1 can be performed successfully.

[0017] In one embodiment, only about 180-200 g of the catalyst is required for removing about 11, 000 kg of hydrogen peroxide from sulfuric acid.

[0018] Preferably, activated carbon is added to the products produced by step S5 for absorbing smell.

[0019] No chlorine ions are generated by the method of the invention when the products are produced. This ensures that the quality products of hydrogen peroxide free are useful for further uses and applications. Particularly, the purified, diluted sulfuric acid (H.sub.2SO.sub.4) finds wide chemical applications.

[0020] Referring to FIG. 2, it shows a table of test reports regarding the invention. It is found that hydrogen peroxide is substantially removed from the purified, diluted sulfuric acid (H.sub.2SO.sub.4) thus can be reused.

[0021] The invention has the following advantages and benefits in comparison with the conventional art:

[0022] The purified, diluted sulfuric acid (H.sub.2SO.sub.4) thus can be reused. Particularly, both products, i.e., copper (II) sulfide (CuS) of the purity and the purified, diluted sulfuric acid (H.sub.2SO.sub.4), are adapted to reuse. Still particularly, the highly purified, diluted sulfuric acid (H.sub.2SO.sub.4) finds wide chemical applications. Therefore, the waste sulfuric acid having hydrogen peroxide, after treated by the method of the invention, can be reused in wide applications.

[0023] The products are reusable. Both products, i.e., purified copper (II) sulfide (CuS) and the purified, diluted sulfuric acid (H.sub.2SO.sub.4), are adapted to reuse by removing hydrogen peroxide from the waste sulfuric acid.

[0024] Copper ions based catalysts do not generate chlorine ions. The copper ions based catalysts can produce purified metallic sulfide and purified, diluted sulfuric acid without chlorine ions being generated. This ensures the apparatus involved in the method steps to be less liable to corrosion, thereby increasing safety of the method.

[0025] While the invention has been described in terms of preferred embodiments, those skilled in the art will recognize that the invention can be practiced with modifications within the spirit and scope of the appended claims.