CN102603081A - Preparation method of degradable cellulose base filler used for water treatment - Google Patents

Abstract

The invention relates to water treatment fillers in the field of environmental protection, in particular to a method for preparing cellulose-based degradable fillers for water treatment, which mainly prepares fibers through the N-methylmorphine-N-oxide process, and cross-links The modification technology further improves the mechanical properties of the filler, and at the same time treats the surface of the filler to make it positively charged, which is more conducive to the adhesion and growth of microorganisms on the surface. The method of the invention is simple and environment-friendly, the fiber prepared by the N-methylmorphine-N-oxide process has good mechanical strength, the prepared filler has a large surface area and a high porosity, is beneficial to protect the growth of microorganisms, and has a good effect in water treatment, and It will not cause secondary pollution and has high application value.

Description

Preparation method of cellulose-based degradable filler for water treatment

technical field

The invention relates to a water treatment filler in the field of environmental protection, in particular to a preparation method of a cellulose-based degradable filler for water treatment.

Background technique

Making wastewater contact with the biofilm grown on the surface of the fixed support, using biodegradation or transforming the organic pollutants in the wastewater is a commonly used wastewater treatment method, that is, the biofilm method. As a medium for the growth and reproduction of microorganisms, biological filler is the core part of biofilm water treatment technology. Currently used fillers such as granular activated carbon, zeolite, quartz sand, plastic, silica gel, ceramic balls, etc., often contain a large amount of toxic and harmful substances, or are difficult to decompose and form solid waste, which is easy to cause secondary pollution. , difficult to deal with.

Using biodegradable materials as biofilm carriers to treat wastewater is a new technology. In the patent CN 1765770A, a cellulose-based biological carrier filler with controllable degradation for water treatment is disclosed. It belongs to the technical field of water treatment fillers. The preparation is to alkalinize and sulfonate cellulose to obtain cellulose viscose, then add foaming agent, and regenerate in dilute acid solution to obtain cellulose-based carrier filler; the controllable degradation modification process of the carrier is to mix the carrier with cross-linked The linking agent ethylene glycol diglycidyl ether is cross-linked to achieve the purpose of modification with controllable degradation rate and no environmental pollution after use. However, during the carrier production process, the release of harmful gases such as by-products H ₂ S and CS ₂ complicates the fiber production process and pollutes the environment. Although the produced fiber has a water washing process before drying, some sulfur compounds will still remain in the fiber. The release of harmful gas will also cause some other problems in production, such as the air bubbles in the fiber make the strength uneven, and the gas accumulation makes the gel-like fiber size change unexpectedly, thereby reducing the performance of the product.

Contents of the invention

The purpose of the present invention is to solve the problem of secondary pollution caused by existing water treatment fillers, and to provide a cellulose-based degradable filler for water treatment that has a simple preparation process, is environmentally friendly, and can produce degradable filler products with good performance. method of preparation.

In order to solve the above technical problems, the present invention is solved through the following technical solutions:

A method for preparing a cellulose-based degradable filler for water treatment, comprising the steps of:

Step a: crush the cellulose material to 500-1000 mesh, add 2-5ml of N-methylmorphine-N-oxide with a water content of 30-50% per gram of cellulose powder, and mix well;

Step b: In the cellulose material in which N-methylmorphine-N-oxide is uniformly dissolved, add a crosslinking agent in a ratio of 10 to cellulose mass ratio (5-20), stir evenly and let it stand for 40- 60min, then place the above mixture in a water bath heater at 40-70℃ and heat for 50-240min;

Step c: Control the temperature to 35-40°C, and add 2-5% of starch by cellulose mass, 10-15% of microorganisms by cellulose mass, and 5-5% by mass of microorganisms to the cross-linked fiber material. 10% nutrients, foam molding, and dry the formed cellulose filler at 45-65°C;

Step d: Submerge the dried cellulose filler in 15-30ml of a mixed solution of polyethyleneimine and NaOH per gram of dry carrier, heat to 40-60°C, stir for 1 hour, take it out and wash it with distilled water, Dry at 45-65°C to obtain the product.

As a preference, the mass fraction of polyethyleneimine in step d is 40-50%; the mass fraction of NaOH solution is 10%.

Preferably, the crosslinking agent is N-methylolamidoamine crosslinking agent.

Preferably, the crosslinking agent is N-methylolacrylamide.

Preferably, the microorganisms are facultative bacteria or anaerobic bacteria.

Preferably, the nutrient substance is any one of glucose, phosphorus salt, and ammonium salt.

Preferably, the cellulose material is rice straw or wheat straw.

The present invention has remarkable technical effect owing to adopted above technical scheme:

(1) The product material cellulose of the present invention is low in cost and easy to obtain, and the production process belongs to a clean production process and is environmentally friendly;

(2) N-methylmorphine-N-oxide has mild dissolution conditions and high solubility to cellulose;

(3) The performance of the filler is good, and the strength of the carrier is improved by cross-linking modification technology, and the surface of the filler is treated to make it positively charged, which is more conducive to the adhesion and growth of microorganisms on the surface;

(4) The filler has a large surface area and high porosity, which is conducive to protecting the growth of microorganisms, and has a good effect in water treatment without causing secondary pollution.

Detailed ways

Below in conjunction with embodiment the present invention is described in further detail:

Example 1

1. Crush the straw to 800 mesh, add 3ml of N-methylmorphine-N-oxide (NMMO·H2O) with a water content of 35% to each gram of straw powder, and mix well;

2. Add 0.5g of N-methylolacrylamide per gram of rice straw powder to the straw cellulose material in which N-methylmorphine-N-oxide is uniformly dissolved, stir evenly and let it stand for 50 minutes, then mix the above mixture Place in a water bath heater at 60°C for 120 minutes;

3. Control the temperature at 35°C, add 2% starch based on the mass of straw cellulose, 10% facultative bacteria based on the mass of straw cellulose, and the mass of facultative bacteria to the crosslinked straw cellulose material Fraction of 5% glucose, foam molding, the formed straw cellulose filler is dried at 55°C.

4. Submerge the dried straw cellulose filler in 15ml of a mixed solution of 40% polyethyleneimine and 10% (mass fraction) NaOH per gram of dry carrier, and stir for 1 hour at 50°C. Take it out, wash it with distilled water, and dry it at 55°C.

The obtained straw cellulose filler had a specific surface area of 2380 m2/m3, a porosity of 87%, and a cellulose cross-linking degree of 8.62%.

Example 2

1. Crush the straw to 800 mesh, add 3ml of N-methylmorphine-N-oxide (NMMO·H2O) with a water content of 35% to each gram of straw powder, and mix well;

2. Add 1.5g of N-methylolacrylamide per gram of straw cellulose to the rice straw powder in which N-methylmorphine-N-oxide is uniformly dissolved, stir evenly and let it stand for 50 minutes, then place the above mixture Heat in a water bath heater at 50°C for 120min;

3. Control the temperature at 35°C. Add 3% starch based on the mass of straw cellulose as a binder and 12% of anaerobic bacteria based on the mass of straw cellulose to the crosslinked straw cellulose material, accounting for Phosphorus salt with anaerobic bacteria mass of 8% is foamed and molded, and the formed straw filler is dried at 55°C.

4. Submerge the dried straw cellulose filler in 15ml of 10% (mass fraction) NaOH solution with a concentration of 45% polyethyleneimine per gram of dry carrier, and stir at 50°C for 1 hour. Take it out, wash it with distilled water, and dry it at 55°C.

The obtained straw cellulose filler had a specific surface area of 2754 m2/m3, a porosity of 91%, and a cellulose cross-linking degree of 10.96%.

Example 3

1. Crush the wheat straw to 800 mesh, add 3ml of N-methylmorphine-N-oxide (NMMO·H2O) with a water content of 35% to each gram of wheat straw powder, and mix well;

2. In the wheat straw in which N-methylmorphine-N-oxide is uniformly dissolved, add 2g of N-methylolacrylamide per gram of wheat straw powder, stir well and let it stand for 50min, then put the above mixture in Heating in a water bath heater at 50°C for 120min;

3. Control the temperature at 38°C, add 4% starch based on the mass of wheat straw cellulose and 15% anaerobic bacteria based on the mass of wheat straw cellulose to the crosslinked wheat straw powder, accounting for anaerobic Ammonium salt with 10% bacterial mass was used for foam molding, and the formed wheat straw cellulose filler was dried at 55°C.

4. Immerse the dry wheat straw cellulose filler in 15ml of 10% (mass fraction) NaOH solution with a concentration of 50% polyethyleneimine per gram of dry carrier, and stir at 60°C for 1 hour. Take it out, wash it with distilled water, and dry it at 55°C.

The obtained wheat straw cellulose filler had a specific surface area of 2812 m2/m3, a porosity of 92%, and a cellulose cross-linking degree of 11.34%.

In a word, the above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the patent of the present invention.

Claims (7)

1. water treatment is characterized in that with the preparation method of cellulose based degradable filler, comprises the steps:

Step a: cellulose materials is crushed to the 500-1000 order, and every gram Mierocrystalline cellulose powder adds N-methyl beautiful jade-N-oxide compound of 2-5ml water cut 30-50%, mixes;

Step b: in N-methyl beautiful jade-N-oxide dissolution homogeneous fibre cellulosic material; In with the Mierocrystalline cellulose quality than (5-20): 10 ratio adds linking agent; Stir and leave standstill 40-60min, place 40-70 ℃ of water-bath heater to heat 50-240min in above mixture again;

Step c: controlled temperature is 35-40 ℃; In the filamentary material after crosslinked; Add again starch 2-5% in the Mierocrystalline cellulose quality, Mierocrystalline cellulose quality meter mikrobe 10-15%, account for the nutritive substance of microbial quality 5-10%, foaming, the cellulose wadding of moulding is dry down at 45-65 ℃;

Steps d: with the exsiccant cellulose wadding, be immersed in by the dried carrier of every gram in the mixing solutions of polymine and NaOH of 15-30ml, and be heated to 40-60 ℃, stirred 1 hour, take out with zero(ppm) water and clean, 45-65 ℃ of drying, product.

2. water treatment according to claim 1 is characterized in that with the preparation method of cellulose based degradable filler: the massfraction of the polymine in the described steps d is 40-50%; The massfraction of NaOH solution is 10%.

3. water treatment according to claim 1 is characterized in that with the preparation method of cellulose based degradable filler: described linking agent is a N-methylol amide amine linking agent.

According to claim 1 or 3 described water treatments with the preparation method of cellulose based degradable filler, it is characterized in that: described linking agent is a N hydroxymethyl acrylamide.

5. water treatment according to claim 1 is characterized in that with the preparation method of cellulose based degradable filler: described mikrobe is amphimicrobe or anerobes.

6. water treatment according to claim 1 is characterized in that with the preparation method of cellulose based degradable filler: described nutritive substance be glucose, microcosmic salt, ammonium salt any.

7. water treatment according to claim 1 is characterized in that with the preparation method of cellulose based degradable filler: described cellulose materials is straw or wheat straw stalk.