CN101733078A - Method for preparing phosphorous-removing adsorbent by using cane shoots leaves - Google Patents

Abstract

A method for preparing a phosphorus-removing adsorbent in the field of environmental protection technology using Zizania leaves, the method comprising the following steps: step 1, taking industrial waste iron sludge and ammonium sulfate, mixing, heating, and impregnating with hydrochloric acid to obtain a solution; step 2, taking Zizania leaves, pulverized, soaked in the solution obtained in step 1; step 3, vacuum filtration and washing; step 4, repeating the operation of step 3 until the cleaning solution obtained after washing is colorless, and the solid is obtained, dried to obtain Zizania leaves Phosphorus removal adsorbent; the technical scheme of the present invention is simple in process and does not require high-temperature roasting, and the obtained adsorbent has a wide range of applicable pH values, good phosphorus removal effect, short time for phosphorus removal by the adsorbent and large adsorption capacity, up to 2.02mg/ g, has a good application prospect for the treatment of eutrophic wastewater.

Description

Method for preparing phosphorus-removing adsorbent by using bamboo leaves

technical field

The invention relates to a preparation method in the technical field of environmental protection, in particular to a method for preparing a phosphorus-removing adsorbent by using bamboo leaves.

Background technique

When the inorganic total nitrogen content of nutrients (generally referring to nitrogen and phosphorus compounds) in the water body is greater than 0.2 mg/L, and the total phosphorus content is greater than 0.02 mg/L, it will cause a large number of water plants (such as algae and large plants) to grow. Chinese phenomenon. The frequent occurrence of algal blooms has seriously affected residents' drinking water safety, aquaculture, and the value of water landscapes, causing huge economic losses. Nitrogen has a complete cycle in nature: biological (organic matter) → ammonia → nitrite → nitrate → biological (organic matter), so it is not easy to enrich in actual water bodies and cause nitrogen pollution. And because there is no complete cycle of phosphorus in nature, phosphorus is easy to enrich and cause pollution. Therefore, the key to preventing eutrophication of water bodies is to control the phosphorus content in them.

At present, the phosphorus removal methods include conventional biological phosphorus removal method, chemical phosphorus removal method and other methods. The biological phosphorus removal method has a long period of phosphorus removal; the chemical phosphorus removal method is simple to operate, but the cost of chemicals is high, and the resulting chemical precipitation is difficult to handle, causing secondary pollution.

Found through literature search to prior art, Indian Journal of Chemical Technology (Indian Chemical Technology Journal), 1999, volume 6, pages 256-262 "Phosphate adsorption studies using carbon prepared from stem bark of Eucalyptus teriticornis Smith (utilizing fine Phosphorus adsorption research on the carbon prepared from the bark of Eucalyptus eucalyptus)" discloses the following technical content: the charcoal prepared from eucalyptus bark is impregnated with sulfuric acid to obtain an adsorbent and is used to adsorb phosphorus, but this method has limited raw materials and complicated processes. Moreover, the adsorption of phosphorus by the prepared adsorbent is greatly affected by the pH value of the solution, and the adsorption amount of phosphorus is all lower than 1 mg/g.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art, and provide a method for preparing a phosphorus-removing adsorbent by using water bamboo leaves. The technical solution of the present invention is simple in process and does not require high-temperature roasting. The obtained adsorbent has a wide range of applicable pH values, good phosphorus removal effect, short time for phosphorus removal by the adsorbent, and large adsorption capacity, up to 2.02 mg/g. Nutritious wastewater has a good application prospect.

The present invention is achieved through the following technical solutions, and the present invention comprises the following steps:

Step 1, taking industrial waste iron sludge and ammonium sulfate, mixing, heating, and impregnating with hydrochloric acid to obtain a solution;

Step 2, taking Zizania zizania leaves, crushing them, and soaking them in the solution obtained in Step 1;

Step 3, vacuum filtration and washing;

Step 4, repeating the operation of step 3 until the cleaning solution obtained after washing is colorless, and a solid is obtained, which is then dried to obtain an adsorbent for removing phosphorus from bamboo leaves.

In step 1, the ratio of industrial waste iron sludge to ammonium sulfate is (1-3):1 by weight.

In step 1, the heating is specifically heating to 150-200°C.

In step 1, the volume percentage of the hydrochloric acid is 10%-37%.

In step 1, the concentration of Fe ³⁺ in the solution is 20-300 g/L.

In step 2, the soaking time is 10-30 hours.

In step 4, the drying is specifically: drying at 60-80° C. for 6-10 hours.

Compared with the prior art, the present invention has the following beneficial effects: one of the raw materials used in the technical solution of the present invention, Zizania aquatica L., has a wide range of sources, low cost, is conducive to the recycling of agricultural waste, and is environmentally friendly. Friendly; at the same time, the technical scheme of the present invention is simple in process, does not require high-temperature roasting, and the obtained adsorbent has a wide range of pH values, good phosphorus removal effect, short time for phosphorus removal by the adsorbent and large adsorption capacity, up to 2.02mg/g , has a good application prospect for the treatment of eutrophic wastewater.

Detailed ways

This embodiment is carried out on the premise of the technical solution of the present invention, and detailed implementation methods and processes are given, but the protection scope of the present invention is not limited to the following embodiments. For the experimental methods without specific conditions indicated in the following examples, the conventional conditions or the conditions suggested by the manufacturer are usually followed.

In the following examples, the "industrial waste slag and iron sludge" is the waste with the most types and the most miscellaneous components in the iron and steel industry. Generally, the mass fraction of iron is 30% to 70%. This technical term is well known to those skilled in the art of.

Example 1

Step 1: Mix industrial waste iron sludge and ammonium sulfate in a ratio of 1:1 according to the weight ratio; heat to 150°C, then impregnate with hydrochloric acid with a volume fraction of 10%, and stir fully after the sample is completely dissolved to obtain rich Iron salt solution containing Fe ³⁺ , so that the concentration of Fe ³⁺ in the solution is 20g/L;

Step 2, taking Zizania bamboo leaves, crushing them, and then soaking the debris in the solution obtained in Step 1 for 10 hours;

Step 3, vacuum filtration and washing; vacuum filtration and washing in this step are carried out simultaneously, that is, washing while suction and filtration, and vacuum filtration is to accelerate the washing speed;

Step 4, repeating the operation of Step 3 until the cleaning solution obtained after washing is colorless, and drying the obtained solid in an oven at 60° C. for 6 hours to obtain an adsorbent for removing phosphorus from Zizania bamboo leaves.

Implementation effect: the adsorbent obtained in this example was added to an aqueous solution of sodium dihydrogen phosphate (NaH ₂ PO ₄ ) with a pH value of 2 for adsorption, and the adsorption effect was 1.54 mg/g.

Example 2

Step 1: Mix industrial waste iron sludge and ammonium sulfate at a ratio of 2:1 according to the weight ratio; heat to 175°C, then impregnate with hydrochloric acid with a volume fraction of 25%, and stir fully after the sample is completely dissolved to obtain rich Iron salt solution containing Fe ³⁺ , so that the concentration of Fe ³⁺ in the solution is 100g/L;

Step 2: Take Zizania bamboo leaves, crush them, and then soak the debris in the solution obtained in Step 1 for 30 hours;

Step 3, vacuum filtration and washing; vacuum filtration and washing in this step are carried out simultaneously, that is, washing while suction and filtration, and vacuum filtration is to accelerate the washing speed;

Step 4, repeating the operation of Step 3 until the cleaning solution obtained after washing is colorless, and drying the obtained solid matter in an oven at 70° C. for 8 hours to obtain an adsorbent for dephosphorization of Zizania bamboo leaves.

Implementation effect: the adsorbent obtained in this example was added to an aqueous solution of sodium dihydrogen phosphate (NaH ₂ PO ₄ ) with a pH value of 7 for adsorption, and the adsorption effect was 2.02 mg/g.

Example 3

Step 1: Mix industrial waste iron sludge and ammonium sulfate at a ratio of 3:1 according to the weight ratio; heat to 200°C, then impregnate with hydrochloric acid with a volume fraction of 37%, and stir fully after the sample is completely dissolved to obtain rich Iron salt solution containing Fe ³⁺ , so that the concentration of Fe ³⁺ in the solution is 300g/L;

Step 2, taking Zizania bamboo leaves, crushing them, and then soaking the debris in the solution obtained in Step 1 for 20 hours;

Step 3, vacuum filtration and washing; vacuum filtration and washing in this step are carried out simultaneously, that is, washing while suction and filtration, and vacuum filtration is to accelerate the washing speed;

Step 4, repeating the operation of Step 3 until the cleaning solution obtained after washing is colorless, and drying the obtained solid in an oven at 80° C. for 10 hours to obtain an adsorbent for removing phosphorus from Zizania bamboo leaves.

Implementation effect: the adsorbent obtained in this example was added to an aqueous solution of sodium dihydrogen phosphate (NaH ₂ PO ₄ ) with a pH value of 10 for adsorption, and the adsorption effect was 1.88 mg/g.

Claims (7)

1. a method utilizing Zizania japonica leaf to prepare phosphorus removal sorbent, is characterized in that, comprises the steps: Step 1, taking industrial waste iron sludge and ammonium sulfate, mixing, heating, and impregnating with hydrochloric acid to obtain a solution; Step 2, taking Zizania zizania leaves, crushing them, and soaking them in the solution obtained in Step 1; Step 3, vacuum filtration and washing; Step 4, repeating the operation of step 3 until the cleaning solution obtained after washing is colorless, and a solid is obtained, which is then dried to obtain an adsorbent for removing phosphorus from bamboo leaves. 2. The method for preparing a phosphorus-removing sorbent by using Zizania japonica leaves according to claim 1, characterized in that, in step 1, by weight, the ratio of industrial waste iron sludge to ammonium sulfate is (1～3): 1. 3. The method for preparing a phosphorus-removing adsorbent by using Zizania ziba leaves according to claim 1, characterized in that, in step 1, the heating is specifically heating to 150-200°C. 4. The method for preparing a phosphorus-removing adsorbent by using leaves of Zizania japonica according to claim 1, characterized in that, in step 1, the volume percentage of the hydrochloric acid is 10% to 37%. 5 . The method for preparing a phosphorus-removing adsorbent by using leaves of Zizania japonica according to claim 1 , characterized in that, in step 1, the concentration of Fe3+ in the solution is 20 to 300 g/L. 6 . The method for preparing a phosphorus-removing adsorbent by using Zizania zizania leaves according to claim 1 , characterized in that, in step 2, the soaking time is 10 to 30 hours. 7. The method for preparing a phosphorus-removing adsorbent by using Zizania bamboo leaves according to claim 1, characterized in that, in step 4, the drying is specifically: drying at 60-80°C for 6-10 hours.