RU1791398C - Method of vanadium extraction from solution - Google Patents

Description

that sulfate-reducing bacteria contained in activated sludge are capable of reducing sulfates under anaerobic conditions to hydrogen sulfide, which forms vanadium insoluble sulfides. The residual vanadium content in the treated effluents is 0.05-0.1 mg / l, which corresponds to

PDC / .. - ..

As follows from the data of this method, the Cu, Fe, NI cations present in the system with vanadium form insoluble metal sulfides, which are removed simultaneously with vanadium.

For example, when treating a solution containing vanadium - 100 mg / l, iron .- 80 mg / l, copper - 5 mg / l and nickel - 10 mg / l, after cleaning the solutions with sulfate-reducing bacteria, the degree of extraction of these metals, respectively, is 99.95% for vanadium, 99.9% for iron and 100% dium nickel (Table 2, Example 12).

The known method is non-selective with respect to vanadium, since it is directed to batch and waste water from metal ions, the sulfides of which are precipitated. : .-. The aim of the invention is to provide selective extraction of vanadium while achieving a high degree of recovery from multicomponent man-made solutions.

To achieve this goal, a method for extracting vanadium from solutions is proposed, which method consists in treating the solutions with Chlorella algae. vulgarls, Largl adapted to vanadium and processing are carried out with a mass ratio of vadani and algae equal to 1: (2.0-2.2), and a pH of 2.5-5.0.,

It was found that the algae Chlbrella vulgarls, Largl, adapted to vanadium, quickly and efficiently sorb only vanadium ions with the formation of complex compounds with surface functional groups of cells in the presence of other metal ions. ......

The sorption capacity of various algae species with respect to vanadium was investigated. The data presented in Table 1 showed that of various types of algae Chloreila vulgarls, 18, Chlorella pyrenoidosa, Scenedesmus obllquus, Chlorella vulgaris, Largl with high sorption capacity in relation to vanadium 154 mg / g, Scenedesmus obliquus cells possess 3) and 400 mg / L - cells of Chlorella vulgarls, Largl (example 5), which respectively extract 30.8% and 80% of vanadium from NaVOs solutions. Indicated

Various algae species were preliminarily adapted to vanadium. Adaptation of Chlorella vulgarls, Largl, and Scenedesmus obllquus cells was carried out by adding Tami vanadate sodium at a concentration of 2.5 g / L in terms of vanadium. Every 7-10 days, the culture was re-plated on fresh nutrient medium for 2 months and grown at pH 6.5-7.0 and

temperature 26-32 ° С and illumination 5-6 thousand lux.

It was experimentally established that the adaptation of algae to vanadium led to an increase in their sorption capacity by 20–25%.

Thus, for adapted Scenedesmus obllquus cells, the sorption capacity increased to 185.2 mg / g with a recovery percentage of 56.7% (Table 1, Example 4).

The best results were obtained for Chlorella vulgarls, Largl cells adapted to vanadium; their sorption capacity was 500 mg / g; up to 100% of the metal was recovered in 1 hour. The high sorption capacity of the algae Chlorella vufgaris, Largl with the claimed process parameters ensured the selective extraction of vanadium from technogenic solutions.

The method is implemented as follows. Algae Chlorella vulgarls, Largl from the collection of the Institute of Plant Physiology of the USSR Academy of Sciences, grown on Tami medium at a temperature of 2b-32 ° C, at a pH of 6.5-7.0, are used as microflora. Seaweed

preliminarily adapted to oanadium, adding sodium vanadate at a concentration of 2.5 g / l to the nutrient medium. Technogenic solutions are complex systems containing cations of various metals: vanadium - 500-2000 mg / l, iron

200-1500 mg / l, aluminum 2000-2800 mg / l, manganese 100-150 mg / l, nickel 20-80 mg / l, r N solution 1.8 ..

Algae Chlorella vulgarls, Largl in the form of a paste are added to the initial vanadium-containing solution. Algae paste was obtained by separating cells from the culture medium by centrifugation at

v 1500 rpm for 20 minutes. The mass ratio of vanadium to algae is 1: (2.0-2.2) and a pH of 2.5-5.0; which is created by adding a 10% NaOH solution. The resulting mixture was stirred for 1-2 hours. The cells are then separated from the liquid, for example by centrifugation for 15 minutes at 1,500 rpm. The precipitate is analyzed for metal content.

The amount adsorbed by the metal cells is determined by X-ray fluorescence analysis on an XR-500 instrument.

Vanadium recovery is considered selective when the amount of impurities in the vanadium-containing sludge does not exceed 5%, which allows the use of the resulting vanadium as an alloying additive.

It has been established that there is an optimal range of pH values of the medium (2.5-5.0), at which the maximum degree of vanadium recovery is achieved with the minimum degree of extraction of the accompanying metals (GABL, 2, Examples 1-7).

When the pH of the medium is below the stated limit, for example, pH 2 (Table 2, example), the cell loses its physiological activity and loses selectivity. Along with vanadium, other metals (Fe, Al, Mn, P) will also be extracted from multicomponent solutions. In this case, the vanadium recovery rate drops to 70%, and the amount of impurities in the vanadium-containing precipitate increases to 20.0%.

An increase in the pH of the medium to 5.5 leads to the hydrolysis of iron and the partial hydrolysis of elyum, the colloidal particles of Fe (OH) 3 and A (OH), along with vanadium, are sorbed on the active sites on top of the HOCTJI algae. The recovery rate of v-NZDUA drops to 85%, and the amount of impurities in the vanadium-containing sludge increases to 22.8% (Table 2, Example 9).

The amount of algae introduced is selected from the condition of complete vanadium recovery. J.:

When the mass ratio of vanadium to algae is below the stated limit, for example 1: 1.9, a sufficiently high degree of vanadium recovery is not ensured. In this case, vanadium is recovered by 90%, and the extraction of impurities is increased to 2.1% (Table 2, Example 10).

The upper limit of the ratio of vanadium to algae is limited in that an increase in the algal content in the system does not increase either the degree of extraction of vinadi or its selectivity and is not economically feasible (Table 2, Example 11).

 and me r. Take 250 ml of the initial technogenic solution containing 0.5 g of vanadium; iron 0.25 g; aluminum 0.5 g; manganese 0.025 g and nickel 0.005 g; added

0

5

0.

fifty

5

0-

fifty

10% solution of MAOH, create in the environment of pH 5.0. Then, algae CMorella vulgaris, Largl, previously adapted to vanadium in the form of a paste in the amount of 3.3 g; containing 1 g of cells in terms of dry matter.

The mass ratio of vanadium to algae is 1: 2. The resulting mixture was stirred for 2 hours. Cells were separated by centrifugation at v 1500 rpm for 15 minutes. Vanadium-containing sediment is analyzed for metal content by X-ray fluorescence analysis on an XR-500 instrument.

The precipitate contains 0.5 g V, 0.014 g Fe, 0.006 g AI, 0.007 g Mn, 0.0003 g NI. The vanadium recovery is 100% and the vanadium impurities contained in the sediment are 4.1% (Table 2, Example 3).

The proposed method for extracting vanadium from solutions has the following advantages compared to the known (prototype):

provides selective extraction of vanadium from multicomponent technogenic solutions, which is characterized by a 95.9-98.6% vanadium content in the sediment, with impurities being 1.23-4.1%;

provides almost 100% recovery of vanadium (the residual vanadium content in the solution is at a MPC level of 0.1 mg / l);

provides efficient extraction of vanadium at high concentrations of vanadium (up to 2 g / L) and associated metals (e.g. Fe up to 1.5 g / L, At - up to 2.8 g / L).

A pilot test of the proposed method for extracting vanadium from solutions will be carried out at the Zaporozhye titanium-magnesium plant in 1990-1991.

FORMULA AND SECTION

A method for extracting vanadium from a solution by treating it with a biomass of microorganisms, followed by separating the vanadium-containing precipitate, such as so that, in order to increase the degree and selectivity of extracting vanadium, the algae biomass Chlorella vulgaris Largl is used, adapted to vanadium, and processing is carried out at a pH of 2.5-5.0 and a mass ratio of vanadium and algae biomass of 1: (2.0-2.2),

Table 1

Sorption capacity (mg / g) of cells with respect to vanadium and its degree of extraction from NaVOa

Concentration of salt 2g / l in terms of V Concentration of cells 4g / l on dry weight

 .. Table2 Extraction of vanapi from aqueous solutions with the help of) algae previously adapted to vanadium

V 2000

Those - 1000 L1 "2000

In 100 Ni -20

V - 2000 Fe - 1000. Al - 2000 Mi - 100 Hi - 20

V - 2000 Fe - 1000 Al 2000 Mp 100 Ni - 20

V - 2000, F "- 1000 Al - 2000 Ip - 100 W - 20

V - 2000 Fe 1000

Al 2000 MP - 100 Hi - 20,

V - 500 .Ft - 250 L1 - 2800 Mn - 120 Ni 40

V 1000 Fe 1500 Al - 2000 tin-150

 iHi - 80

V 2000 tr - 1000 Al - 2000 Mn - 150 tli - 80

V - 2000 Fe - 1000 Al - 2000 Mn - 150 Hi 80

0 V - 2000 Fe - 1000 Al 2000 Mr. 150

Ni - 80

The proposed method. -

Chlorella Culgarls 2 2.5 1: 2

Larg 1

0.1 980 1991 97 -19

2.3.51: .0.1075 1990 97.5 19

25.01: 2.0.1942 1976 97.2 16

25.01: 20.1.971.5 I9S9 97.5 18.3

22.51: 2.20.1972 1991 96.9 18.64

12.551: 2.10.1249.7P. 2795.8 118.8 39.2

22.51: 2.10.11477.5 1994.0 147.75 77.6

Beyond Geilchen

22.01: 2; 0600825 1855 131.0 69.0

25.51: 2.0300 625 1SSO 142.5 77.6

22.51: 1.92009SO 1990 145.5 76.8

pH 4.5 Contact time - 1 hour

1 980 1991 97 -19

1075 1990 97.5 19

, 1942 1976 97.2 16

, 1.971.5 I9S9 97.5 18.3

.1972 1991 96.9 18.64

.1249.7P. 2795.8 118.8 39.2

.11477.5 1994.0 147.75 77.6

00825 1855 131.0 69.0

00 625 1SSO 142.5 77.6

009SO 1990 145.5 76.8

V Fe Al tltl Mi

V - Fe Al Hn Hi V

.F.

Al

. Hn

Ni

V - Fe “Al) 1n Ni

V fe

Al mn

Ni V - Fe i Al. lln

VI

V - Fe Al

ttn Ni

V

Fe

Al

Hn ni

V fe

Al

Hn

Wt

V

Ke

Al

Hn

Ni

100

 2.0

 0.45

 3.0

 5,0

100

 2.5

 0.5

 2.5 5.0

100

 5.8

 1.2

 2.8

 6.5

100

 2.85

 0.55

 0.5

 6.2

100

 2,8

 0.45

 3,1

 6.8

100.0

 0.9

 0.15

 1,0

 2.0

100.0

 1.5 0.3

 1,5

 3.0

70.0

 17.5

 7.25

 12.67

 13.75

85.0

 37.5

 6.0

 5,0

 3.0

90.0

 2.0

 0.5

 3.0

 4.0

98.4 t, 60:

98.1 1.90

95.9 4.10:

97.9 2.10

97.97 2.03

98.77 J.23

36. TJ 3.21

80.0 20.0

77.2 22.8

97.9 2.1

V - 100

  80 C - 3 Hi - 10

Prototype

Sulfatvos - 10 stvnvvlye - days 5,2 yuciv bacteria

Continuation of Table 2

0.1

V 99. "5 US - 99.9 C - 100.0 III - 100.0

51.3 8.7