Oxalic acid is used to bleach wood when it has been stained by iron. There are many ways iron works it’s way into wood and this is the best remover for those stains when you are working on refinishing wood surfaces. Weighs 16 oz.
Oxalic Acid Wood Bleach
SAFELY REMOVE STAINS WITHOUT BLEACHING WOOD COLOR
Have you ever removed the finish from a piece of furniture and found black stains or black rings from metal pots or prolonged water exposure? Have you ever removed the finish from a floor and found black or deep brown pet urine stains in the wood, which no amount of sanding will take out? These are all iron stains caused by the chemical reaction of tannins in the wood mixing with the trace metals in urine and water.
Oxalic acid (Oxalate) is an all-natural, organic compound with the formula HO2C−CO2H. It’s found in vegetables like sorrel, spinach, and rhubarb. There are many processes to extract it from vegetation, but modern methods manufacture it through the oxidation of carbohydrates or glucose using nitric acid or vanadium pentoxide. It is a relatively strong acid for its acid group. It is important to use protective gear and eye goggles when handling oxalic acid.
The main use of oxalic acid is as a bleach, particularly with wood and to remove iron stains all while not bleaching the wood. (If you do want to remove the natural color of wood, you would need a two-part bleach of sodium hydroxide and hydrogen peroxide.) For small spots, it is suggested that users mix about two tablespoons of it in a quart of hot tap water and allow it to dissolve. For larger spots or entire sections of a floor, there are directions on the next tab. Wood bleach is also great for removing water spots and rust stains.
When dissolved, use an artist brush and paint it in the mixture on the stained areas only. Allow drying. The stain will lighten. If it does not disappear, then do another coat. You may need to coat it three or four times, allowing time to dry between coats. Once the stain is gone you can sometimes get a slight halo effect around the area where the stain was bleached. To take care of this, saturate a rag with the acid solution and wipe a thin coat over the stain and surrounding area. Allow drying. This should take care of the stains. Once the stains are gone you need to neutralize the acid so it will not react with your wood finish. Mix up two tablespoons of borax in a quart of hot water. Saturate a rag with the borax solution and wipe the floor and allow to dry. Borax, like oxalic acid, is a natural product.
Directions for Use
SURFACE PREPARATION: Wood must be free of all coatings, waxes & oils. Use appropriate strippers and cleaners to remove coatings.
MIXING: ALWAYS WEAR RUBBER GLOVES, EYE PROTECTION & PROTECTIVE CLOTHING WHEN USING THIS PRODUCT. Dissolve contents of this package with one gallon of hot water.
- Add entire contents of jar to 2 gallons of water or 2 tablespoons per quart.
- Apply hot solution w/scrub brush, old paint brush or mop of large jobs. Apply liberally allowing the solution to remain on surface until bleached to desired lightness.
- If solution cools before job is finished, reheat the solution being careful not to allow it to come to a boil.
- Rinse treated area repeatedly w/clean water and allow to dry.
- Test removal of the bleach from the dried wood by wiping the surface w/dark-colored cloth checking for a powdery residue. If powder is present, rinse again w/clean water and allow to dry.
- Wood grain may be raised as a result of application of this product. Ensure all bleach residue is gone & then sand wood & finish w/desired product.
KEEP OUT OF REACH OF CHILDREN AND PETS.
MAY BE TOXIC TO SMALL PETS.
Working with older wood has its complexities, one of which is stains that sanding doesn’t remove. Many times, these stains are due to the chemical reaction of tannins with trace metals in the wood. These chemical reactions happen for various reasons, including dampened hardware resting against the wood for long periods or pet urine remaining in contact with the surface over time. Fortunately, wood bleach products such as Oxalic Acid by The Real Milk Paint Co. can help you remove stains from the wood without changing its original coloration. This formulation works on both small and large areas, and it also helps when you need to eliminate water spots or rust stains.
How Oxalic Acid Is Made
Oxalic Acid derived from common vegetables such as spinach, rhubarb and sorrel. The extraction process typically means oxidizing carbohydrates and glucose in this plant vegetation with either nitric acid or vanadium pentoxide. This process creates powdered crystals that activate completely when mixed with hot water, making it simple to store between uses and mix when needed.
Difference Between Oxalic Acid and Other Wood Bleaches
When exploring how to bleach wood, you probably encountered other options such as two-part wood bleaches and wondered what the difference is between them and Oxalic Acid. The main difference is that Oxalic Acid returns wood surfaces to their original color or natural hue, while two-part bleaches typically lighten the wood all over. Additionally, two-part bleaches also remove color from many pigments and dyes, not just the wood it’s used upon. These formulations are called two-part bleaches because they literally come in two parts you have to mix before bleaching. One package typically contains lye and the other hydrogen peroxide. When you’re ready to use two-part bleach, you either mix the two components together and apply them to surfaces or apply one after the other, depending on the brand.
Benefits of Bleaching Wood with Oxalic Acid
One of the main benefits of working with Oxalic Acid is that it’s one of the safer wood bleaching products as long as you take the proper precautions. While still extremely corrosive and dangerous to handle without protective gear, this all-natural organic compound offers an environmentally friendly option for bleaching wood. Since it doesn’t change the color of unstained areas, you don’t have to be as careful in application as with stronger wood bleaches, and it also removes chemical stains and tannin discoloration from bare wood, making it a versatile option when building or restoring furniture and homes.
How to Use Oxalic Acid to Bleach Wood in Small and Large Spaces
When you just need small stains removed on areas of furniture where hardware rested against the wood, Oxalic Acid allows you to mix up a small amount and save the rest for later. To do this, mix 2 tablespoons of our powder formulation per quart of water, then apply it to the area with a fine paintbrush. For larger areas such as floors with extensive damage from pet urine, just mix the whole package with a gallon of water. Once mixed, cover the flooring with the hot solution by using a mop for quick, easy application.
Safety Considerations for Using Oxalic Acid Wood Bleach
Though natural, Oxalic Acid is a strong acid and requires proper gear for safe use. This means that before you get started, you need thick rubber or vinyl gloves and eye goggles. You should work in a well-ventilated space and use a personal respirator if you have any sensitivities, and consider wearing a dust mask while you work even if you don’t. Additionally, wear a long-sleeved shirt and long pants to better protect yourself should you splash the mixture as you work. To further reduce or contain injury risks, keep a pail of fresh water on hand while you work to immediately wash Oxalic Acid off your skin or out of your eyes should you accidentally expose bare skin to the chemical. Like with all strong chemicals, store Oxalic Acid out of reach from kids and pets when not in use.
Wood Bleaching Dos and Don’ts
When considering how to use wood bleach like Oxalic Acid in your projects, keep these dos and don’ts in mind to ensure optimal results.
- Do Treat Oxalic Acid with Respect: Though all-natural, it can’t be stressed enough that Oxalic Acid is also highly dangerous. Because it comes in crystal form, inhalation can cause lung damage even before you mix it, so be sure to work in a well-ventilated area and possibly wear a personal respirator.
- Don’t Use Oxalic Acid with Metal Containers: Oxalic Acid eats away at metal and has the potential to corrode it so much that your mixture leaks and damages you or other surfaces. Instead, use ceramic or glass bowls to mix and contain your mixture as you work.
- Do Clean Wood Properly Before Bleaching: Before applying Oxalic Acid, be sure that surfaces are completely stripped of all wax, finishes and oils. Also, remove any metal hardware, even if it’s not the hardware that caused the stain you wish to remove.
- Don’t Expect All Wood to React the Same: Some types of wood bleach better than others, so if you’re unsure of how the wood you wish to bleach reacts with Oxalic Acid, consider doing a spot test. You can test on an area of your project that remains unseen on completion, or you can test bare wood of the same type as that you’re planning on bleaching.
- Do Work Slowly and Carefully: Just because Oxalic Acid doesn’t bleach unstained areas doesn’t mean you should be sloppy in application. Because it’s a dangerous chemical, maintain respect for the medium and apply it carefully in smooth, even coats, with either a soft rag or a paintbrush.
- Don’t Leave Excess Oxalic Acid Behind: If you apply too much Oxalic Acid, be sure to wipe it away with a dry cloth immediately. This reduces risks of accidents and helps ensure your completed project looks its best.
- Do Neutralize Oxalic Acid as You Work: Oxalic Acid by The Real Milk Paint Co. neutralizes easily with Borax. After coating your surface, mix 2 tablespoons of Borax with 1 quart of water, then use the mixed solution to wipe down the wood you’re bleaching once the Oxalic Acid dries.
- Don’t Mix Oxalic Acid Ahead of Time: Like with other wood bleaches, newly mixed Oxalic Acid works best when used right away. If you mix it ahead of time, the chemicals typically weaken and reduce effectiveness.
Supplies for Oxalic Acid Wood Bleach Projects
In addition to the personal protective gear mentioned above, you need several other supplies for Oxalic Acid wood bleaching projects. First, you need a glass or ceramic bowl for mixing it with water and something to mix it with such as a clean paint stirrer. You also need clean water, both to rinse off any Oxalic Acid that gets on you or other surfaces and to mix with Borax when you’re ready to neutralize your surface. For application, scrub brushes, old paint brushes and mops work best. Additionally, to check for residue after bleaching and neutralizing, keep a soft dark rag on hand that easily shows powder and dust.
How to Use Wood Bleach
When you’re ready to start your wood bleaching project, gather all the necessary supplies in the area you plan to work. Again, when working with strong chemicals, be sure the area is well-ventilated and large enough that you can move around easily as you work through the process.
Oxalic Acid works on bare wood, so the first step to using this formulation is cleaning your surface thoroughly. This means clearing away old finishes, and The Real Milk Paint Co. has you covered there with stripping products designed for practically any finish you need to clean. For surfaces covered in modern paints and urethane, consider using Soy-Gel Professional Paint Remover, which removes several layers of shellac, paint and other finishes with one application. This low-VOC formula offers powerful stripping yet is safe enough for indoor use. Use Milk Paint Stripper for surfaces covered in Real Milk Paint. Once you’ve stripped the surface or if you’re working with bare wood, then wipe the surface down with Trisodium Phosphate to completely remove any residue.
Mixing Oxalic Acid
When using Oxalic Acid from The Real Milk Paint Co., mixing is simple. For smaller batches, mix 2 tablespoons of our Oxalic Acid powder with 2 quarts of hot water in a glass or ceramic container. For larger jobs, mix the entire package with 2 gallons of hot water. Remember, acids typically weaken over time, so your Oxalic Acid mixture works best when freshly mixed.
Apply Wood Bleach Mixture
Grab an old scrub brush, paintbrush or mop once you mix your solution, then use it to liberally apply Oxalic Acid to your surface. Be sure to wipe off any of the solution that splatters on other surfaces, and keep the Oxalic Acid solution on until the wood reaches your desired level of lightness. If the stain is still there after the solution dries, reapply it with the same technique and allow it to dry again.
Neutralize the Oxalic Acid
When you achieve the look you want, neutralize the Oxalic Acid solution with Borax. To do this, mix 2 tablespoons of Borax with 1 quart of water, then apply the mixed solution liberally over the surface. Though this isn’t a hard step you must perform, it does help ensure a safer working environment and reduces injury risks as you complete your project. Once the solution dries, you’re ready to rinse the surface with water.
Rinse the Treated Area with Water
Once the wood achieves the lightness level you prefer, rinse the treated area with water. You likely need to rinse the area multiple times to be sure you’ve removed all the Oxalic Acid, so don’t be shy about rinsing. When you finish, allow the bleached finish time to dry. It’s very important to remove neutralize and rinse away residual Oxalic Acid. So, don’t be afraid to repeat these steps if necessary.
Check for Residue
Once you’ve treated the wood, rinsed it clean and allowed the surface to dry, use the dark rag in your supplies to check for residue. To do this, simply run it across the dried surface, then check it for any powder left behind. If you find residue on the dark rag, then repeat the rinsing step and check for residue again. Once your rag comes back clean, move on to the next step.
Complete Your Build or Restoration
Once your surface reaches the desired level of lightness and you’ve rinsed, neutralized and removed all residue, you’re ready to add color or shine to the wood. Because your wood is bare and now clean, you can simply work as usual with your choice of Real Milk Paint colors, finishing creams or glazes or waxes such as Good Ol’ Brown Wax or Soapstone Sealer and Wood Wax.
Getting the look you want from the original wood used to build antiques doesn’t have to be tricky when you use Oxalic Acid to remove stains or restore surfaces to their original beauty. Safe and effective when you take the proper precautions, Oxalic Acid works equally well for experienced and beginner DIYers, with a forgiving formulation that doesn’t make your surface lighter than it was originally. By combining Oxalic Acid with other products from The Real Milk Paint Co., you can beautify vintage pieces with ease and create new furnishings or flooring that mimics the look of antiqued items without breaking your back or your budget.
Material Safety Data Sheet
126 Commerce Dr
Hohenwald TN 38462
24 Hour Emergency Phone: Chem-Tel Inc. 800-255-3924
Emergency Telephone Numbers:
24 hrs. Chem-Tel 800-255-3924 (within continental US)
24 hrs. 813-248-0585 (collect) (outside continental US)
Updated: June 2015
SECTION 1 – CHEMICAL PRODUCT AND COMPANY IDENTIFICATION
PRODUCT NAME : WOOD BLEACH OXALIC ACID
UPC NUMBER : 7422160240, 7422165072
PRODUCT USE/CLASS : Spackling
MANUFACTURER: DAP INC.
2400 BOSTON STREET
BALTIMORE, MD 21224
24 HOUR EMERGENCY:
TRANSPORTATION: 1-800-535-5053 (352-323-3500)
MEDICAL : 1-800-327-3874 (513-558-5111)
PREPARE DATE: 11/1/1999
REVISION NO.: 0
Date Updated: 6/9/2015
DAP INC. : 1-888-DAP-TIPS (1-888-327-8477)
SECTION 2 – COMPOSITION/INFORMATION ON INGREDIENTS
ITEM CHEMICAL NAME CAS NUMBER WT/WT% RANGE
01 Oxalic acid 144-62-7 100 %
ACGIH OSHA COMPANY
ITEM TLV-TWA TLV-STEL PEL-TWA PEL-CEILING TLV-TWA SKIN
01 1 mg/m3 2 mg/m3 1 mg/m3 2 mg/m3 N.E. NO
(See Section 16 for abbreviation legend)
Remaining ingredients are not considered hazardous per the OSHA Hazard Communication Standard.
Listed Permissible Exposure Levels (PEL) are from the U.S. Dept. of Labor OSHA Final Rule Limits (CFR 29 1910.1000); limits may vary between states.
SECTION 3 – HAZARDS IDENTIFICATION
EMERGENCY OVERVIEW: WARNING! Can cause eye and skin irritation. May be harmful or fatal if swallowed.
POTENTIAL HEALTH EFFECTS:
EFFECTS OF OVEREXPOSURE – EYE CONTACT: Can cause permanent eye injury. Symptoms include stinging, tearing, redness and swelling of the eyes.
EFFECTS OF OVEREXPOSURE – SKIN CONTACT: Can cause skin irritation. Symptoms include redness, burning, and swelling of skin. May cause burns.
EFFECTS OF OVEREXPOSURE – INHALATION: Breathing this material may be harmful or fatal. May cause severe irritation and burns to the nose, throat and respiratory tract.
EFFECTS OF OVEREXPOSURE – INGESTION: Swallowing this material may be harmful or fatal. Can cause severe stomach and intestinal irritation, nausea, vomiting, diarrhea and abdominal pain. May cause burns of the mouth, throat and digestive tract.
EFFECTS OF OVEREXPOSURE – CHRONIC HAZARDS: Central nervous system effects, cardiovascular effects, kidney damage.
MEDICAL CONDITIONS WHICH MAY BE AGGRAVATED BY CONTACT: No information
PRIMARY ROUTE(S) OF ENTRY: Inhalation, skin contact
SECTION 4 – FIRST AID MEASURES
Eye Contact: Flush with large quantities of water until irritation subsides. Contact a physician.
Skin Contact: Wash with soap and water. If irritation of skin persists, contact a physician.
Inhalation: Remove to fresh air. Contact a physician immediately.
Ingestion: DO NOT INDUCE VOMITING. Contact a physician or Regional Poison Control Center immediately.
SECTION 5 – FIRE FIGHTING MEASURES
FLASH POINT: N.A. LOWER EXPLOSIVE LIMIT: N.A.
(SETAFLASH CLOSED CUP) UPPER EXPLOSIVE LIMIT: N.A.
AUTOIGNITION TEMPERATURE: N.A.
EXTINGUISHING MEDIA: Alcohol foam, water fog, carbon dioxide, dry chemical
UNUSUAL FIRE AND EXPLOSION HAZARDS: No information available
SPECIAL FIREFIGHTING PROCEDURES: Use water spray to cool exposed surfaces.
SECTION 6 – ACCIDENTAL RELEASE MEASURES
SPILL OR LEAK PROCEDURES: Sweep up excess powder. Place remaining powder into containers.
SECTION 7 – HANDLING AND STORAGE
HANDLING INFORMATION: KEEP OUT OF REACH OF CHILDREN. Keep containers away from excessive heating and freezing. Avoid skin and eye contact. Do not inhale dusts of this product.
STORAGE INFORMATION: Keep container closed when not in use.
OTHER PRECAUTIONS: None.
SECTION 8 – EXPOSURE CONTROLS/PERSONAL PROTECTION
ENGINEERING CONTROLS: While mixing, provide sufficient mechanical ventilation (local or general exhaust) to maintain exposure below PEL and TLV.
RESPIRATORY PROTECTION: A respiratory protection program that meets OSHA 1910.134 and ANSI Z88.2 requirements must be followed whenever workplace conditions warrant a respirator’s use.
EYE PROTECTION: Goggles or safety glasses with side shields.
SKIN PROTECTION: Gloves recommended for contact with skin.
OTHER PROTECTIVE EQUIPMENT: Provide eyewash and coveralls if body contact may occur.
SECTION 9 – PHYSICAL AND CHEMICAL PROPERTIES
Boiling Range: N.A.
Appearance: No data
Solubility in H2O: N.A.
Specific Gravity: 1.653
Vapor Pressure: N.A.
Physical State: Powder
Vapor Density: N.A.
Odor Threshold: N.A.
Evaporation Rate: N.A.
(See Section 16 for abbreviation legend)
SECTION 10 – STABILITY AND REACTIVITY
CONDITIONS TO AVOID: N.A.
INCOMPATIBILITY: Chlorites, furfuryl alcohol, hypochlorites, silver, strong alkalies, strong oxidizing agents. Acid reacts with most metals to release hydrogen gas which can form explosive mixtures with air.
HAZARDOUS DECOMPOSITION PRODUCTS: Acid vapors, carbon dioxide and carbon monoxide.
HAZARDOUS POLYMERIZATION: Will not occur under normal conditions.
STABILITY: This product is stable under normal storage conditions.
SECTION 11 – TOXICOLOGICAL PROPERTIES
No product or component toxicological information is available.
SECTION 12 – ECOLOGICAL INFORMATION
SECTION 13 – DISPOSAL CONSIDERATIONS
WASTE MANAGEMENT/DISPOSAL: Dispose of according to Federal, State, and Local Standards. Discarded material should be incinerated at a permitted facility. Liquids cannot be disposed of in a landfill. Do not reuse empty container. State and Local regulations/restrictions are complex and may differ from Federal regulations. Responsibility for proper waste disposal is with the owner of the waste.
EPA WASTE CODE – If discarded (40 CFR 261):
SECTION 14 – TRANSPORTATION INFORMATION
DOT PROPER SHIPPING NAME: Not Regulated by D.O.T.
DOT HAZARD CLASS: NONE
DOT UN/NA NUMBER: NONE PACKING GROUP: NONE
SECTION 15 – REGULATORY INFORMATION
U.S. FEDERAL REGULATIONS: AS FOLLOWS –
OSHA: Hazardous by definition of Hazard Communication Standard (29 CFR 1910.1200)
SARA SECTION 313:
This product contains the following substances subject to the reporting requirements of Section 313 of Title III of the Superfund Amendments and Reauthorization Act of 1986 and 40 CFR Part 372:
———– CHEMICAL NAME ———– CAS NUMBER WT/WT % RANGE
TOXIC SUBSTANCES CONTROL ACT:
This product contains the following chemical substances subject to the reporting requirements of TSCA 12(B) if exported from the United States:
———– CHEMICAL NAME ———– CAS NUMBER
NEW JERSEY RIGHT-TO-KNOW:
The following materials are non-hazardous, but are among the top five components in this product:
———– CHEMICAL NAME ———– CAS NUMBER
The following non-hazardous ingredients are present in the product at greater than 3%:
———– CHEMICAL NAME ———– CAS NUMBER
CALIFORNIA PROPOSITION 65:
WARNING: The chemical(s) noted below and contained in this product, are known to the state of California to cause cancer, birth defects or other reproductive harm:
———– CHEMICAL NAME ———– CAS NUMBER
INTERNATIONAL REGULATIONS: AS FOLLOWS –
CANADIAN WHMIS: This MSDS has been prepared in compliance with Controlled
Product Regulations except for use of the 16 headings.
CANADIAN WHMIS CLASS: No information available.
SECTION 16 – OTHER INFORMATION
HMIS RATINGS – HEALTH: 2 FLAMMABILITY: 0 REACTIVITY: 0
PREVIOUS MSDS REVISION DATE: N.A.
VOC less water, less exempt solvents: 0 g/L
VOC material : 0 g/L
LEGEND: ACGIH – AMERICAN CONFERENCE OF GOVERNMENTAL INDUSTRIAL HYGIENISTS
N.A. – NOT APPLICABLE
N.E. – NOT ESTABLISHED
PEL – PERMISSIBLE EXPOSURE LIMIT
NTP – NATIONAL TOXICOLOGY PROGRAM
SARA – SUPERFUND AMENDMENTS AND REAUTHORIZATION ACT OF 1986
STEL – SHORT TERM EXPOSURE LIMIT
TLV – THRESHOLD LIMIT VALUE(8 HR. TIME WEIGHTED AVERAGE OR TWA)
VOC – VOLATILE ORGANIC COMPOUND
NJRTK – NEW JERSEY RIGHT TO KNOW LAW
N.D. – NOT DETERMINED
This data is offered in good faith as typical values and not as a product specification. No warranty either expressed or implied, is hereby made. The recommended industrial hygiene and safe handling procedures are believed to be generally applicable. However, each user should review the recommendations in specific context of the intended use and determine if they are appropriate.