Sulfur Handbook

Southern Ionics INCORPORATEDINCORPORATED

CREATIVE SOLUTIONS TODAY

SII

Sulfur Products Handbook CREATIVE SOLUTIONS TODAY

Southern Ionics Incorporated (SII) was founded in 1980. The corporate headquarters and research facilities are located in West Point, Mississippi. The company has eleven facilities located in Port Allen, Louisiana; Baton Rouge, Louisiana; Calhoun, Tennessee; Chickasaw, Alabama; Columbus, Mississippi; Lake Charles, Louisiana; Midlothian, Texas; Pasadena, Texas; Terrell, Texas; Tuscaloosa, Alabama; and West Point, Mississippi.

CUSTOMER FOCUS

SII manufactures and markets the following products: Southern Ionics is committed to building a team of motivated individuals who can advance the technology of our business, manufacture quality products, and ALUMINUM CHLORIDE provide our customers with the service and know-how to maximize the value POLYALUMINUM CHLORIDE of our products. We provide comprehensive technical service and application assistance for our products through our engineering, technical, sales, and R&D ALUMINUM CHLOROHYDRATE personnel. Southern Ionics’ quality management system is certified to meet ISO 9001:2000 Standards. Potable water treatment products are NSF certified ALUMINUM SULFATE SOLUTION for use. Many of our products meet the Food Chemical Codex specifications and are classified by the FDA as GRAS (Generally Recognized As Safe). AQUA-CAT™ AQUA AMMONIA

CEMENT MANUFACTURING ADDITIVES CUSTOMER SERVICE Our number one priority is meeting our customers’ expectations. SII has a SI-SOLV™ FOR DEINKING RECYCLED PULP centrally located Customer Service Department with toll free telephone and SODIUM ALUMINATE facsimile numbers for the customers’ convenience in ordering during business hours, and there is a toll free number for after hours and emergencies. The SODIUM BISULFITE after-hours operator is equipped with pertinent information to handle any customer request. This allows for 24 hour, 7 days a week, 365 days a year SODIUM SULFITE service to handle customers’ needs. Inventory management is also available. SII personnel simply contact the SODIUM THIOSULFATE customer via an electronic dial-up remote tank level monitor system. SII then MAGNESIUM SULFATE schedules delivery based on the customer’s inventory targets and usage rates. Customer contacts for inventory management are also made by scheduled VARIOUS ZIRCONIUM COMPOUNDS phone or internet queries.

CUSTOM COMPOUNDS & FORMULATIONS PRODUCT INFORMATION Southern Ionics manufactures sodium bisulfite solutions and sodium sulfite solutions at Pasadena, Texas and Tuscaloosa, Alabama. Sodium Thiosulfate solutions are produced at Baton Rouge, Louisiana and Pasadena, Texas. All three products are aqueous solutions. Standard products are a 40% sodium bisulfite solution, 15% sodium sulfite solution, and 30% sodium thiosulfate solution. Other concentrations of these products are available; however, the solubility of the materials and individual customer requirements dictate the practical concentrations that can be produced, shipped and stored (see Temperature Solubility Curves on pages 18 & 19.) The chemistry of the three products is similar in that they are sulfur based reducing agents and will react with many of the same oxidizing agents. They are also similar in that they can be used in reactions that add functionality to the compounds produced.

1 The solutions range from mildly acidic, as in the case of bisulfite, to slightly basic, in the case of sodium sulfite and sodium thiosulfate. The pH of these sulfite solutions dictates the existence of sodium bisulfite and/or sodium sulfite (see Speciation of Sulfurous Acid-Bisulfite-Sulfite vs. pH on page 21). Sodium thiosulfate on the other hand is more stable and usable at pH levels above 8. There is a long list of applications where these products are used. The most significant uses are: • In chemical reactions as a raw material • As a reducing agent to destroy active halogen compounds • As an oxygen scavenger (sulfite and bisulfite) • As a sulfonating agent for organics • Acrylic polymerization catalyst component (bisulfite) • Metals reduction • Photographic developer compounding • Pulp and paper production • Food preservation (bisulfite)

MANUFACTURING PROCESS While there are a number of potential processes that yield bisulfite, sulfite, and thiosulfate, all commercial processes react sulfur or sulfur dioxide with alkali in an aqueous solution. Southern Ionics produces sodium bisulfite by burning elemental sulfur in air to form a gas containing sulfur dioxide. The combustion gas is cooled and absorbed into an alkaline solution, either caustic soda or soda ash, to form sodium bisulfite. Sodium bisulfite is further reacted with caustic soda or soda ash to produce sodium sulfite. By adding additional sulfur and heat, the sodium sulfite can be converted to sodium thiosulfate solution.

SODIUM THIOSULFATE PROCESS

Sodium Sulfite Solution REACTOR Heat Sulfur

SODIUM Loading FILTER THIOSULFATE STORAGE

2 3 4 5 6 SAFETY

SAFETY Sodium bisulfite solution is classified as a Hazardous Chemical Class A by DOT standards. Sodium sulfite solutions and sodium thiosulfate solutions are not regulated by DOT; however, all three products deserve respect as reactive chemicals in regard to personal safety during handling and use. Contact with eyes, skin, or mucous membranes can cause severe irritation and even burns. To avoid irritation, these products should be handled in well-ventilated areas and all personal protective equipment should be utilized. Appropriate personal protective equipment, including safety glasses, chemical goggles, rubber boots, chemical resistant gloves, rubber apron, and face shield should be worn. In the case of sodium bisulfite, respirators should be worn unless ventilation is adequate to keep concentrations of sulfur dioxide below exposure standards. Some individuals are highly sensitive to sulfur dioxide and sulfites. These individuals should not be placed in a situation where they could become exposed to these products or the vapors from the products. THE MSDS SHOULD BE READ, UNDERSTOOD, AND FOLLOWED BEFORE HANDLING THESE OR ANY OTHER CHEMICALS.

FIRST AID Eyes: Immediately flush eyes with a large amount of water for at least 15 minutes. Get prompt medical attention. Skin: If exposed to skin: Wash skin thoroughly with soap and water. Remove contaminated clothing while continuing to apply water. Get prompt medical attention if irritation persists. Inhalation: Move victim to fresh air. If breathing is difficult, give oxygen. If breathing has stopped, start artificial respiration. Get prompt medical attention. Ingestion: Induce vomiting by giving 2 glasses of water to drink and touching back of subject’s throat with finger. IMMEDIATELY see a physician. Never give anything by mouth to an unconscious person. Contact local Poison Control Center. In case of ingestion of sodium thiosulfate, induce vomiting if gross amounts are swallowed. See MSDS for more information.

FIRE PROTECTION

FLAMMABLE LIMITS EXTINGUISHING MEDIA SPECIAL FIREFIGHTING PROCEDURES

Sodium Bisulfite Non Flammable Use extinguishing media Move containers promptly out of fire zone. If appropriate for surrounding fire. removal is impossible, cool containers with water spray. Remain upwind. Avoid breathing noxious fumes (sulfur dioxide) from fire-exposed material.

Sodium Sulfite Non Flammable Use extinguishing media Wear complete fire service protective equipment, appropriate for surrounding fire. including full-face piece MSHA/NIOSH approved self-contained breathing apparatus. Use water to cool fire-exposed container/structure/protect personnel. Water or foam may cause frothing, if product is heated above 93ºC/200ºF.

Sodium Thiosulfate Non Flammable Use extinguishing media For fires involving this material wear SCBA. appropriate for surrounding fire.

7 REACTIVITY

Stability Conditions To Avoid Incompatibility Hazardous Decomposition Products Hazardous Polymerization

Sodium Bisulfite Stable Avoid exposure to Avoid contact Thermal decomposition may yield the Will not occur. excessive heat. Sulfur with acids and following: sulfur dioxide – toxic dioxide may be released oxidizing agents. fumes. if allowed to contact strong acids or if dried material is overheated.

Sodium Sulfite Stable Avoid exposure to Liberates sulfur Oxides of sulfur fumes emitted when Will not occur. excessive heat. Sulfur dioxide in the heated to decomposition dioxide may be released presence of if allowed to contact strong acids. strong acids or if dried material is overheated.

Sodium Thiosulfate Stable Avoid exposure to Strong Acids If dried material is overheated, sulfur Will not occur. excessive heat. Sulfur dioxide is given off. dioxide may be released if allowed to contact strong acids or if dried material is overheated.

SYMPTOMS & EFFECTS OF OVEREXPOSURE

Sodium Bisulfite Sodium Sulfite Sodium Thiosulfate Eyes Severe Irritation; Mild irritation Slight irritation corneal burning possible Skin Irritation – dermatitis Mild irritation Moderate to low irritant. Inhalation Irritation of nose, throat, and lungs Sulfite-sensitive individuals, N/A – coughing – shortness of breath upon inhalation of this product may experience a severe allergic reaction. Ingestion Harmful if swallowed. Oral exposure or swallowing Up to 12 grams can be taken daily by Gastrointestinal irritation; allergic may produce gastrointestinal mouth with no ill effects except catharsis. reaction; In large doses may cause: upset. Sulfite sensitive abdominal pain, control nervous individuals may experience a system depression, diarrhea, severe allergic reaction. depression and death. Toxicity LD50 in rats 2000 mg/kg orallyLD50 in rats is 5.66 g/kg. Large doses internally have a cathartic Dermal toxicity in LD50 rabbit action. is >16.0 g/kg

TRANSPORTATION REQUIREMENTS

DOT DOT UN/ID Packing Other Shipping Name Classification Number Group Labels Bisulfites, inorganics, Sodium Bisulfite 8 UN2693 III Corrosive aqueous solutions, n.o.s. (Sodium Bisulfite)

Sodium Sulfite Sodium Sulfite Solution N/A N/A N/A N/A Sodium Thiosulfate Sodium Thiosulfate N/A N/A N/A N/A Solution

8 SODIUM BISULFITE SOLUTION

BULK STORAGE Bulk storage of sodium bisulfite solution is straightforward; there are four important considerations addressed here that can have major impact on the successful planning of a storage system.

VOLUME OF SOLUTION STORED Standard bulk deliveries of sodium bisulfite solution are 4,200 gallons by tank truck and 17,000 gallons by tank car. It is normal practice to install tanks that have at least 1.5 times the capacity of the expected deliveries. Other factors will also influence the decision on the tank volume. The rate at which the solution will be used could require a larger tank. Installing a smaller tank could increase the cost of deliveries for the life of the system. It is important to remember that sodium bisulfite solution is quite stable, and bulk economics are favored even if deliveries are required only a few times a year.

T ANK CONSTRUCTION Sodium Bisulfite Solution is corrosive to mild steel, brass, and copper alloys. Premium resin FRP, 316 SS, rubber-lined carbon steel, or polyethylene are all suitable material for sodium bisulfite storage tanks. Tanks can be of single wall or double wall construction. Local regulations on containment will determine what is required in a specific situation, but materials such as sodium bisulfite normally require either double wall construction or some form of containment. Tank insulation is generally recommended for single walled tanks and even for some double walled tank installations. Most installations in the south do not require tank heaters. If a heating system is considered necessary because of the specific product or location, the equipment selected should avoid prolonged product contact with surfaces heated above 150 degrees F. Some type of recirculation is generally adequate in preventing such situations. A schematic of a typical sodium bisulfite storage tank is shown on the next page. Southern Ionics personnel are available for consultation and to answer specific questions.

STORAGE TANK VAPORS The vapor above a solution of sodium bisulfite contains water vapor and sulfur dioxide. The vapor pressure of the solution is low (32.5 mm Hg) and not a significant concern except during unloading into the tank. During a normal unloading into the tank, vapor from the tank is displaced through the tank vent. The vapor displaced by unloading a 4,200 gallon tank truck will contain about 0.2 pounds of sulfur dioxide at 25 degrees C. This vapor can be discharged to the atmosphere at many locations, but may require special handling in some situations. Small vent scrubbers, as shown in the tank schematic, or piping to return the vapor to the tank trailers can handle this issue.

STORAGE TEMPERATURE Sodium Bisulfite Solution is sensitive to storage temperatures. The product is shipped at about 90 degrees F. The recommended storage temperature is 60 to 95 degrees F. Forty-percent (40%) sodium bisulfite will begin to crystallize at approximately 43 degrees F. Care must be taken to prevent the 40% product from falling to this level or below. Tank insulation is generally sufficient to do this, but if material is stored for long periods during cold weather, heating of the product could be required. In any event, if heating is required, isolated temperatures above 150 degrees and bulk temperatures above 100 degrees F should be avoided. 9 10 STORAGE AND HANDLING

Southern Ionics has experience with customers with tanks in many different locations and can make recommendations consistent with your particular area. Please contact your Southern Ionics technical/sales representative if you have questions or need additional information.

PIPING AND PUMPS Stainless steel, PVC, rubber-lined steel, CPVC, and Teflon lined steel piping are recommended for sodium bisulfite service. Pumps with wetted parts of these materials are suitable as well. Any piping exposed to the outdoors should be insulated, and if the system runs intermittently, or if temperatures get to freezing or below, heat tracing the piping is recommended. Piping assembly should be via welded or flanged connection. Threaded connections are discouraged due to the difficulty in maintaining a positive seal with aqueous solutions of this type.

DELIVERIES AND UNLOADING Tank truck deliveries are the most common bulk deliveries. Tank car deliveries are possible but will not be addressed here. Southern Ionics has its own tank trucks and makes many of the deliveries with this equipment; however, common carrier tank trucks are also used on occasion to supplement our equipment and assure timely delivery. Five thousand (5,000) to seven thousand (7,000) gallon stainless steel tank trailers are used to deliver sodium bisulfite solution. These trailers are equipped with 40 feet of 2” chemical hose with cam and groove fittings. The trucks are capable of unloading with their own air supply; however, it is faster to unload using a customer supplied unloading pump or plant air regulated at 25 psi. In special situations, a truck mounted transfer pump can be provided; however, there is an extra cost assessed for each such delivery. A product transfer pump is required (either a truck mounted pump or a pump provided by the customer) if vapor recovery to the trailer is required. The tank trailers are 40 feet long, and with the tractor, the entire rig may be as long as 70 feet. This information should be kept in mind to provide adequate access for the tank truck for deliveries. The unloading area, and particularly the location where the trailer is placed for unloading, should be arranged to contain any spill. The customer is also asked to provide for the disposal of the product remaining in the hoses when delivery is completed. The driver will attempt to minimize the volume of this material, but, typically, several gallons of product are drained from the hoses at the end of the unloading. On arrival at the delivery location, the tank truck driver will report to designated customer personnel with appropriate paperwork and will verify the specific tank and connections for unloading. The driver will be equipped with all required personal protective gear and will adhere to the customer’s safety practices and policies. The driver will hook up the unloading hoses and operate valves, pump, and any other necessary equipment to enable the unloading. The driver will also close all valves as required, unhook all hoses, and dispose of any product from the hoses as directed by customer personnel. Any special requirements during deliveries should be discussed with Southern Ionics personnel prior to delivery, no later than at the time the purchase order is placed.

11 SODIUM SULFITE & SODIUM THIOSULFATE

Bulk storage of sodium sulfite and sodium thiosulfate solutions is simple and straightforward. The following considerations can have a major impact on the successful planning of a storage system.

VOLUME OF SOLUTION STORED Standard bulk deliveries of sodium sulfite solution are 4,600 gallons by tank truck and 19,500 gallons by tank car. For sodium thiosulfate, the respective volumes are 4,300 gallons and 18,200 gallons. It is normal practice to install tanks that have at least 1.5 times the capacity of the expected deliveries. Other factors will also influence the decision on the tank volume. The rate at which the solution will be used could require a larger tank. Installing a smaller tank may increase the cost of deliveries for the life of the system. It is important to remember that these solutions are quite stable, and bulk economics are favored even if deliveries are required only a few times a year.

T ANK CONSTRUCTION Neither sodium sulfite solution nor sodium thiosulfate is corrosive to mild steel. However, we recommend polyethylene, premium resin FRP, 316 SS to minimize the pickup of iron that would happen to some degree with mild steel. Aluminum, copper, brass, or zinc fittings will be attacked by the alkalinity in sulfite and thiosulfate solutions, and their use should be avoided. Tanks can be of single wall or double wall construction. Local regulations on containment will determine what is required in a specific situation. Since these materials are not considered hazardous, regulations are generally less strict than with sodium bisulfite, but local regulations and/or company standards should be consulted. Tank insulation is generally recommended for single walled tanks and even for some double walled tank installations for sodium sulfite solutions. Sodium thiosulfate tanks may or may not require insulation since the crystallization temperature is lower for this product. Most installations in the South do not require tank heaters for either product. If a heating system is considered necessary because of the specific product or location, the equipment selected should avoid prolonged product contact with surfaces heated above 180 degrees F. Some type of recirculation is generally adequate in preventing such situations. A schematic of a typical tank installation for sodium sulfite and sodium thiosulfate storage tank is shown on the next page. The schematics are similar to sodium bisulfite, but no vent scrubber is required. Neither of these products have sulfur dioxide in the vapor above the solutions. Southern Ionics personnel are available for consultation and to answer specific questions.

STORAGE TEMPERATURE Sodium sulfite solution and, to a lesser degree, sodium thiosulfate solutions are sensitive to storage temperatures. The products are shipped at between 90 and 140 degrees F. The recommended storage temperature range for these products is 60 to 80 degrees F, but temperatures as high as 150 degrees are not a problem for the product. Fifteen percent (15%) sodium sulfite will crystallize at approximately 40 degrees F. Care must be taken to prevent the fifteen percent (15%) product from falling to this level or below. Thirty percent (30%) sodium thiosulfate will crystallize at about 14 degrees F. Tank insulation is generally sufficient to deal with ambient temperatures in the South, but, if material is stored for long periods during cold weather, heating of the product could be required. In any event, if heating is required, isolated temperatures above 180 degrees and bulk temperatures above 150 degrees F should be avoided. 12 13 STORAGE AND DELIVERY

PIPING AND PUMPS Stainless steel, CPVC piping, and plastic-lined steel piping are recommended for sodium sulfite and or sodium thiosulfate service. Pumps with wetted parts of these same materials are suitable as well. Any piping exposed to the outdoors should be insulated, and if the system runs intermittently, or if temperatures get to freezing or below, heat tracing the piping is recommended. Piping assembly should be via welded or flanged connection. Threaded connections are discouraged due to the difficulty in maintaining a positive seal with aqueous solutions of this type.

DELIVERIES AND UNLOADING Tank truck deliveries are the most common bulk deliveries. Tank car deliveries are possible but will not be addressed here. Southern Ionics has its own tank trucks and makes many of the deliveries with this equipment; however, common carrier tank trucks are also used on occasion to supplement our equipment and assure timely delivery. Five thousand (5,000) to seven thousand (7,000) gallon stainless steel tank trailers are used to deliver sodium bisulfite solution. These trailers are equipped with 40 feet of 2” chemical hose with cam and groove fittings. The trucks are capable of unloading with their own air supply; however, it is faster to unload using a customer supplied unloading pump or plant air regulated at 25 psi. In special situations, a truck mounted transfer pump can be provided; however, there is an extra cost assessed for each such delivery. The tank trailers are 40 feet long, and with the tractor, the entire rig may be as long as 70 feet. This information should be kept in mind to provide adequate assess for the tank truck for deliveries. The unloading area, and particularly the location where the trailer is placed for unloading, should be arranged to contain any spill. The customer is also asked to provide for the disposal of the product remaining in the hoses when delivery is completed. The driver will attempt to minimize the volume of this material, but, typically, several gallons of product are drained from the hoses at the end of the unloading. On arrival at the delivery location, the tank truck driver will report to designated customer personnel with appropriate paperwork and will verify the specific tank and connections for unloading. The driver will be equipped with all required personal protective gear and will adhere to the customer’s safety practices and policies as advised. The driver will hook up the unloading hoses and operate valves, pump, and any other necessary equipment to enable the unloading. The driver will also close all valves as required, unhook all hoses, and dispose of any product from the hoses as directed by customer personnel. Any special requirements during deliveries should be discussed with Southern Ionics personnel prior to delivery, no later than at the time the purchase order is placed.

14 EQUIPMENT SUPPLIERS

PUMPS Ernst Flow Ind COMPRESSOR FITTINGS STORAGE TANKS Goulds Pumps P.O. Box 925 FOR TUBING – FRP TANKS 240 Fall Street Farmingdale, NJ 07727 Swagelok Red Ewald, Inc. Seneca Falls, NY 13148 800-992-2843 29500 Solon Road P.O. Box 519 315-568-2811 www.ernstflow.com Solon, OH 44139 Karnes City, TX www.gouldspumps.com www.swagelok.com 800-242-3524 www.redewald.com Flowserve Corporation VAPOR SCRUBBERS Tube Fittings Division Rotating Equipment Div. Bionomic Industries Inc. 3885 Gateway Blvd. Augusta Fiberglass P.O. Box 1145 777 Corporate Drive Columbus, OH 43228 Rt. 2 Box 138 Dayton, OH 45401 Mahwah, NJ 07430 914-279-7070 Highway 3 South 937-226-4000 800-311-6767 www.parker.com Blackville, SC 29817 www.flowserve.com www.bionomicind.com 803-284-2246

Branch Environmental STORAGE TANKS Tankinetics, Inc. STORAGE TANK Corp. – METAL TANKS P.O. Box 1195 CONSERVATION P.O. Box 5265 Reco USA Harrison, AR 72601 VENT/BREATHER Somerville, NJ 08876 P.O. Box 4147 870-741-3626 The Protectoseal Company 908-526-1114 West Columbia, SC 29171 Viatec Process/Storage 225 West Forester Avenue www.branchenv.com 803-794-3360 Systems Bensenville, IL 60106 www.recousatanks.com 630-595-0800 EST Corporation P.O. Box 99 www.protectoseal.com P.O. Box 890 Paul Mueller Company Belding, MI 48809 Quakertown, PA 18951 P.O. Box 828 800-942-4702 Groth Corporation 215-538-7000 Springfield, MO 65801 Troy Mfg, Inc. P.O. Box 15293 800-683-5537 Indusco Inc. Houston, TX 77020 www.muel.com 200 Preston Road 800-552-2960 P.O. Box 43447 Henderson, TX 75653 www.grothcorp.com Birmingham, AL 35243 Alloy Fabricators, Inc. 903-657-9404 205-967-7721 P.O. Box 650 AC Plastiques L&J Technologies Trenton, GA 36752 (Shand & Jurs) 800-275-7565 1395 Montee Chenier 5911 Butterfield Road STORAGE TANKS DESIGN www.alloyfab.com Les Cedres, Quebec JOP 1L0 Hillside, IL 60162 450-455-3311 708-236-6000 STANDARDS American Petroleum Southwest Tank & Treator www.ljtechnologies.com Manufacturing Diamond Fiberglass Institute Fabricators, Inc. P.O. Box 340 1220 L. Street, Northwest P.O. Box 106 MAGNETIC TANK Washington, D.C. 20005 Henderson, TX 75653 903-657-3556 Victoria, TX 77902 LEVEL GAUGES 202-682-8000 361-572-4040 www.api.org Email: [email protected] ISE – Magtech www.diamondfiberglass.com 907 Bay Star Blvd API 650 – Welded Steel Dal-Worth Fabrication Webster, TX 77598 Belco Manufacturing Tanks for Oil Storage 2750 E. Main Street 800-221-3653 P.O. Box 210 API 653 Grand Prairie, TX 75050 www.isemagtech.com 800-325-8265 Belts, TX 76513 API 2000 – Venting 800-251-8265 Atmospheric and Low- www.dalworthfabrication.com K-Tek www.belco-mfg.com Pressure Storage Tanks 18321 Swamp Road Southern Tank & Repair Prairieville, LA 70769 American Society of P.O. Drawer 697 800-735-5835 RESIN MANUFACTURERS Mechanical Engineers Grand Bay, AL 36541 www.ktekcorp.com 3 Park Avenue 251-865-6153 AND RESIN NAMES New York, NY 10016 Jogler 800-843-2763 Dow – Derekane 9715 Derrington Ashland – Hetron Houston, TX 77064 Reichold – Dion 800-223-8469 www.jogler.com 15 TYPICAL PRODUCT INFORMATION

16 17 The specific gravity of these reducing agents is not a dependable indication of concentration. Impurities such as sodium sulfate can vary and cause variations in the specific gravity of solutions. The specific gravity information given here is typical of that expected based on concentration but is provided as a means of roughly determining the relationship between volume and weight of the solutions. It can also be used to make rough dilutions of concentrated solutions.

The solubility information provided is intended to assist in making deci- sions about the use and storage of the specific sulfur chemical. In practice, these solutions become super- saturated as they approach the indicated temperature, and the com- pound may stay in solution several degrees below the indicated temperature. Disturbing a supersaturat- ed solution or adding anything that will encourage crystallization is very likely to cause a significant number of crystals to form very rapidly.

In addition, information on the water freezing point for dilute solutions of these sulfur chemicals is given to help manage storage solutions. As indicated, solutions of sodium bisulfites, sulfites and thio- sulfates can be diluted to lower the freezing point to minimize cold weather storage problems.

18 19 20 21 STABILITY OF SODIUM BISULFITE SOLUTIONS

Sodium bisulfite solutions (SBS) will react with oxygen during storage, resulting in a reduction in the sodium bisulfite assay, an increase in the level of sulfates, and a decrease in pH. The graph

below shows the change in bisulfite assay (%NaHSO3) as a function of time for a drum of 40% sodium bisulfite solution stored under ambient conditions. The drum was substantially full and vented to the atmosphere. The particular situation described here represents less than ideal storage conditions but does provide some useful information about the decomposition of SBS.

As can be seen, after 138 days storage, the %NaHSO3 decreased from 39.1% to 37.6%. The %Na2SO4 increased from 0.65% to 1.99%, and the pH decreased from 4.6 to 3.3.

Our experiences suggest that SBS in storage containers closed (or significantly closed) to the atmosphere and at recommended storage temperatures can be stored for six (6) months with little or no decomposition. If not sure of how closed to the atmosphere a particular SBS storage container is, it is recommended that assay, pH, and sulfate levels be checked every 4 to 6 weeks to determine suitability for a particular use. For proper storage conditions, consult the storage and handling section of this handbook.

22 Research facilities explore products and applications for SII customers.

SII’s large trucking fleet assures on-time delivery. Production capacity is supported by extensive storage capabilities.

Sophisticated technology at Southern Ionics ensures product consistency.

HOW TO ORDER: To place an order, obtain samples, prices, and/or technical information from any location in the continental United States, call Customer Service toll free: 800/953-3585 or use Customer Service Fax: 800/953-3588.

CORPORATE HEADQUARTERS: OPERATIONS:

Baton Rouge LA * ** 201 Commerce Street Port Allen, LA * P.O. Drawer 1217 Calhoun, TN * ** Chickasaw (Mobile), AL * ** West Point, Mississippi 39773 Columbus, MS (Barge Terminal) Telephone: 662/494-3055 Westlake, LA * ** Midlothian, TX (Transloading) Fax: 662/494-2828 Pasadena, TX * ** E-Mail: [email protected] Terrell, TX ** Tuscaloosa, AL * * ISO 9001:2000 Certified Website: www.southernionics.com West Point, MS * ** ** NSF International Certified

SOUTHERN IONICS IS AN EQUAL OPPORTUNITY EMPLOYER N/F/H/V

Southern Ionics INCORPORATED